Patent Publication Number: US-11654359-B2

Title: Information processing device, extraction device, information processing method, and extraction method

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a U.S. National Phase of International Patent Application No. PCT/JP2019/013847 filed on Mar. 28, 2019, which claims priority benefit of Japanese Patent Application No. JP 2018-125071 filed in the Japan Patent Office on Jun. 29, 2018. Each of the above-referenced applications is hereby incorporated herein by reference in its entirety. 
     FIELD 
     The present disclosure relates to an information processing device, an extraction device, an information processing method, and an extraction method. 
     BACKGROUND 
     One of the interesting thins of content such as a computer game is that a player can feel successful or accomplished when he/she succeeds in a highly difficult task by finely operating a controller or finely giving an action instruction or when he/she acquires a skill difficult to learn. For this reason, there is known a system that causes a computer to simply learn a game (e.g., Non Patent Literature 1). However, it may take a long time for training to acquire a highly difficult skill. Therefore, training content is known with which a technique can be acquired step by step. 
     CITATION LIST 
     Non Patent Literature 
     
         
         Non Patent Literature 1: David Silverl and others, “Mastering the game of Go with deep neural networks and tree search”, ARTICLE, doi:10.1038/nature16961 
       
    
     SUMMARY 
     Technical Problem 
     However, the training content is uniform, and it has been difficult to effectively support improvement in game learning level according to experience or skill of each individual. 
     Therefore, the present disclosure proposes an information processing device, an extraction device, an information processing method, and an extraction method that are configured to effectively support improvement in game learning level. 
     Solution to Problem 
     To solve the problem described above, an information processing device includes: an output control unit that, when a game status approaches a specific phase, outputs guiding command information guiding to a reproduced game status where the specific phase is reproduced, to a game device. 
     Advantageous Effects of Invention 
     According to the present disclosure, improvement in learning level can be effectively supported. It should be noted that the effect is not necessarily limited to this description and may have any effect described in the present disclosure. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG.  1    is a schematic diagram illustrating an example of an information processing system according to a first embodiment of the present disclosure. 
         FIG.  2    is an example of a functional block diagram illustrating an extraction device and an information processing device according to the first embodiment of the present disclosure. 
         FIG.  3    is a schematic diagram illustrating an example of data configurations of first history information and second history information according to the first embodiment of the present disclosure. 
         FIG.  4    is a graph illustrating extraction of a specific phase according to the first embodiment of the present disclosure. 
         FIG.  5    is a schematic diagram illustrating an example of a display screen according to the first embodiment of the present disclosure. 
         FIG.  6    is a graph illustrating an output of guiding command information according to the first embodiment of the present disclosure. 
         FIG.  7    is a flowchart illustrating an example of a procedure of extraction processing according to the first embodiment of the present disclosure. 
         FIG.  8    is a flowchart illustrating an example of a procedure of information processing according to the first embodiment of the present disclosure. 
         FIG.  9    is a schematic diagram illustrating an example of an information processing system according to a modification of the first embodiment of the present disclosure. 
         FIG.  10    is a schematic diagram illustrating an example of an information processing system according to a second embodiment of the present disclosure. 
         FIG.  11    is a flowchart illustrating an example of a procedure of information processing according to the second embodiment of the present disclosure. 
         FIG.  12    is a schematic diagram illustrating an example of an information processing system according to a third embodiment of the present disclosure. 
         FIG.  13    is an example of a functional block diagram illustrating an extraction device and an information processing device according to a third embodiment of the present disclosure. 
         FIG.  14    is a flowchart illustrating an example of a procedure of information processing according to the third embodiment of the present disclosure. 
         FIG.  15    is an example of a functional block diagram illustrating an extraction device and an information processing device according to a fourth embodiment of the present disclosure. 
         FIG.  16    is a flowchart illustrating an example of a procedure of extraction processing according to the fourth embodiment of the present disclosure. 
         FIG.  17    is a hardware configuration diagram illustrating an example of a computer that achieves functions of an extraction device and an information processing device according to the present disclosure. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Embodiments of the present disclosure will be described below in detail with reference to the drawings. In each of the following embodiments, the same portions are denoted by the same reference symbols, and a repetitive description thereof will be omitted. 
     First Embodiment 
     [Configuration of Information Processing System  1  According to First Embodiment] 
       FIG.  1    is a schematic diagram illustrating an example of an information processing system  1  of the present embodiment. 
     The information processing system  1  includes an extraction device  10 , an information processing device  12 , and a game device  14 . The extraction device  10  and the game device  14  are communicably connected via a network N. Note that the extraction device  10  and the game device  14  may be directly connected via a connection cable so as to be communicated with each other. The extraction device  10  and the information processing device  12  are directly connected via a connection cable so as to be communicated with each other. The extraction device  10  and the information processing device  12  may be wirelessly connected. Furthermore, the extraction device  10  and the information processing device  12  may be communicably connected via the network N. Still furthermore, the extraction device  10  and the information processing device  12  may include software modules that operate (in parallel with a game body) on the game device  14 . 
     The game device  14  is a device that executes a game. The game represents content executed on a computer. Specifically, the game represents a simulation game to virtually advance an actual event or experience, or a computer game. In the game, a game status changes depending on a command signal input in response to an operation command or the like given by a player. The player is an agent that transmits the command signal to the game. Specifically, the player is a person (user) or a computer that automatically learns operations of the game. In the present embodiment, a description is made of an example where the player is a person. 
     The game device  14  includes, for example, a read only memory (ROM) drive, executes a game program in response to insertion of a game ROM into the ROM drive, and operates as the game device  14 . Note that the game device  14  is also configured to operate as an emulation device that executes an image file of the game program by activating an emulator program. Note that the emulator program may be acquired via the network N or may be pre-installed before shipment. 
     An input unit  16  and an output unit  18  are connected to the game device  14  in a wired or wireless manner. The input unit  16  is an input interface device for a player U to input an operation to the game device  14 . The input unit  16  outputs a command signal in response to an operation command given by the player U to the game device  14 . The input unit  16  includes a controller, keyboard, touch panel, pointing device, mouse, input button, or the like. Note that in the present embodiment, the player U who operates the input unit  16  will be described as a first player U 1 . 
     The output unit  18  is a display that displays a game image. The output unit  18  is a display for visual confirmation by the first player U 1  during a game. The output unit  18  includes, for example, a known liquid crystal display (LCD), an organic electro-luminescence (EL), or the like. The output unit  18  may further have a speaker function that outputs sound, in addition to an image display function. 
     The game device  14  outputs an internal state of a game to the information processing device  12 . Details of information (game status) to be output will be described later. In the present embodiment, the information processing device  12  is connected to the game device  14  and the input unit  16 . In other words, the information processing device  12  is connected between the game device  14  and the input unit  16 . Therefore, the input unit  16  transmits a command signal to the game device  14  via the information processing device  12 . 
     The extraction device  10  extracts a specific phase of a game. The specific phase is a specific phase of a plurality of phases included in the game. Details of the specific phase will be described later. The extraction device  10  outputs a specific phase list including the extracted specific phase to the information processing device  12 . The information processing device  12  outputs various information to the game device  14  on the basis of the specific phase included in the specific phase list acquired from the extraction device  10  (details will be described later). 
       FIG.  2    is an example of a functional block diagram illustrating the extraction device  10  and the information processing device  12 . 
     [Configuration of Extraction Device According to First Embodiment] 
     The extraction device  10  includes a control unit  20 , a UI (user interface) unit  23 , a communication unit  26 , a storage unit  30 , and a communication unit  28 . The UI unit  23 , the communication unit  26 , the storage unit  30 , and the communication unit  28  are connected to the control unit  20  so as to exchange data or signals. 
     The UI unit  23  receives various operations input by the player U and outputs various information. The UI unit  23  includes an input unit  22  and a display unit  24 . The input unit  22  receives various operations input by the player U. The input unit  22  includes, for example, a keyboard, pointing device, mouse, input button, or the like. The display unit  24  displays various information. The display unit  24  includes an organic EL or LCD. Note that the input unit  22  and the display unit  24  may be integrally constituted to form a touch panel. 
     In the present embodiment, the UI unit  23  is operated by a fourth player U 4 . The fourth player U 4  is a player who plays a role different from the first player U 1 . Note that the first player U 1  may also serve as the fourth player U 4 . The fourth player U 4  is, for example, an administrator of the information processing system  1 . The UI unit  23  may be a terminal device carried by the fourth player U 4 . The terminal device includes a known personal computer, portable terminal, or the like. When the UI unit  23  is the terminal device, the control unit  20  preferably communicates with the UI unit  23  of the terminal device via the communication unit  28 . 
     The communication unit  26  is a communication interface for directly communicating with the information processing device  12 . The communication unit  28  is a communication interface for communicating with various devices such as the game device  14  via the network N. 
     The storage unit  30  stores various information. In the present embodiment, the storage unit  30  stores first history information  30 A and second history information  30 B. 
     The first history information  30 A is information indicating a history of games played by the first player U 1 . The game history may be referred to as a game log. The second history information  30 B is information indicating a history of games played by the second player U 2 . The second player U 2  is a player U with a higher game learning level than the first player U 1 . Note that the history information (the first history information  30 A and the second history information  30 B) includes at least one or more, preferably, a plurality of game-play episodes. 
     The history information, such as the first history information  30 A or the second history information  30 B, is represented by a time-series set of game statuses. The game status represents information about an internal state of a game provided by a game program. Specifically, the game status is represented by, a screen output to the output unit  18 , the position or activity state of a character or avatar that moves in response to an operation command given by a player U in a game, a state of a surrounding environment other than the character or avatar, a game score, and the like. The state of the surrounding environment includes the position or state of an object other than the character or avatar in the game, brightness, weather, or the like. Note that the game status changes depending on the type or content of a game and is not limited to the above description. 
     The game status changes according to a command signal input from the input unit  16  in response to an operation command given by a player U or the like. Specifically, such a process that the player U inputs for a certain game status a command signal, the game status transitions to a next game status in response to the command signal, and the player U inputs for the next game status a command signal is repeated, and the game proceeds in response to the operation commands given by the player U. In the following, a command signal from the first player U 1  will be described as a first command signal. Furthermore, a command signal from the second player U 2  will be described as a second command signal. 
       FIG.  3    is a schematic diagram illustrating an example of data structures of the first history information  30 A and the second history information  30 B. 
     The first history information  30 A includes a time-series set  42 A of first game statuses st obtained by the first player U 1 . Timing is indicated by t. In the present embodiment, as an example, t is represented by an integer of 1 or more. Each of the first game statuses st indicates a game status changed in response to a first command signal at- 1  (the last operation command) from the first player U 1 . Note that in the following description, the first command signal at- 1  will be simply referred to as a first command signal at. Specifically, the time-series set  42 A of first game statuses st is a time-series set of previous game statuses achieved by inputting the first command signals at to the game device  14  by the first player U 1  in the past. 
     The first command signal at is a command signal from the first player U 1 . As described above, t indicates timing. Note that the first history information  30 A may include both of the time-series set  42 A of first game statuses st and a time-series set  42 B of the first command signals at. In other words, the first history information  30 A may include a plurality of pairs of the first game status st and the first command signal at. Furthermore,  FIG.  3    illustrates an example of a plurality of pairs of (s1, a1), . . . , and (st, at) as a pair of the first game status st and the first command signal at included in the first history information  30 A. However, the first history information  30 A may include a plurality of sets of sequences of (s1, a1), . . . , and (st, at). 
     The second history information  30 B includes a time-series set  40 A of second game statuses St obtained by the second player U 2 . As described above, t indicates timing. Each of the second game status St indicates a game status changed in response to a second command signal At from the second player U 2 . The second command signal At is a command signal from the second player U 2 . As described above, t indicates timing. 
     Note that the second history information  30 B may include both of the time-series set  40 A of second game statuses St and a time-series set  40 B of the second command signals At. In other words, the second history information  30 B may include a plurality of pairs of the second game status St and the second command signal At. Furthermore,  FIG.  3    illustrates an example of a plurality of pairs of (S1, A1), . . . , and (St, St) as a pair of the second game status St and the second command signal At included in the second history information  30 B. However, the second history information  30 B may include a plurality of sets of sequences of (S1, S1), . . . , and (St, St). 
     Returning to  FIG.  2   , the description will be continued. The extraction device  10  collects the first history information  30 A and the second history information  30 B from one or more game devices  14  or external devices via the network N and stores the history information in the storage unit  30 . 
     The control unit  20  controls the extraction device  10 . The control unit  20  includes an extraction unit  20 A, a display control unit  20 B, a classification unit  20 C, an assignment unit  20 D, and a communication control unit  20 E. 
     Part or all of the extraction unit  20 A, the display control unit  20 B, the classification unit  20 C, the assignment unit  20 D, and the communication control unit  20 E may be achieved, for example, by causing a processing device such as a CPU to execute a program, that is, by using software, may be achieved by using hardware such as an integrated circuit (IC), or may be achieved by using both of the software and the hardware. 
     The extraction unit  20 A extracts a specific phase of a game on the basis of both of the first history information  30 A and the second history information  30 B. 
     The specific phase indicates a specific phase in the game. In the present embodiment, the specific phase is a phase as a learning target for the first player U 1 . Specifically, the specific phase is represented by a time-series set of game statuses. Note that the specific phase may represent a game status at a certain timing. In the present embodiment, as an example, a description is made of a case where a specific phase is represented by a time-series set of game statuses at each of a plurality of timings. 
     The extraction unit  20 A extracts one or more specific phases and generates a specific phase list including one or more specific phases. 
     The specific phase list is represented by the following Formula (1). 
     
       
         
           
             
               
                 
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     In Formula (1), τ represents the specific phase list. In Formula (1), τ 1  to τ n  each represent a specific phase (n is an integer of 1 or more). In Formula (1), S is a time-series set of second game statuses St belonging to each of a plurality of specific phases n. In other words, a specific phase is represented by a time-series set of second game statuses St. 
     The extraction unit  20 A uses the time-series set  42 A of first game statuses st shown in the first history information  30 A and the time-series set  40 A of second game statuses St shown in the second history information  30 B to extract a specific phase. 
       FIG.  4    is a graph illustrating extraction of a specific phase. In some cases, the time-series set  40 A of second game statuses St obtained according to second command signals from the second player U 2  and the time-series set  42 A of first game statuses st obtained according to first command signals from the first player U 1  have a game status having a distance equal to or less than a first threshold. Specifically, in some cases, a second game status St achieved by an operation command given by the second player U 2  with a higher learning level and a first game status st achieved by an operation command given by the first player U 1  with a lower learning level have an approximate match. 
     Therefore, in the time-series set  40 A of second game statuses St, the extraction unit  20 A identifies a time point P where a distance to the time-series set  42 A of first game statuses st is equal to or less than the first threshold. For the first threshold, an upper limit of the distance is preferably set at which a second game status St is considered to match a first game status st. In addition, the first threshold is preferably adjusted appropriately according to the content of a game, a skill level of the first player U 1 , or the like. Furthermore, for a distance between game statuses, a value derived from a predetermined function that measures a closeness between game statuses may be used. As the function that measures a closeness between game statuses, various functions can be considered depending on the characteristics of games. In a case where a game screen is used as a game status, the sum of squares of differences between screens can also be used. In some cases, the distance is calculated by paying attention only to some variables (e.g., the position coordinates of a main character) in a game status. In the example illustrated in  FIG.  4   , it is assumed that the extraction unit  20 A identifies P 1 , P 2 , and P 3 , as the time point P where a value is equal to or less than the first threshold. Note that timing t of a game status corresponding to P 1  is illustrated where a suffix is reset so that the value of t is identical in the time-series sets  40 A and  42 A. 
     Next, in the time-series set  40 A of second game statuses St, the extraction unit  20 A designates a range from the identified time point P where a value is equal to or less than the first threshold to a time point P′ where a distance to the time-series set  42 A of first game statuses st is equal to a second threshold (see distance L 2  in  FIG.  4   ) that is larger than the first threshold, as a specific phase τ. 
     The second threshold is preferably set in advance according to the content of a game, a skill level of the first player U 1 , or the like. Furthermore, at least one of the first threshold and the second threshold may be appropriately changeable according to an operation command or the like given by the player U. 
     In this way, in the time-series set  40 A of second game statuses St, the extraction unit  20 A extracts, as the specific phase τ, a phase during a period from the time point P where the distance to the time-series set  42 A of first game statuses st of the first player U 1  is equal to or less than the first threshold to the time point P′ where the distance exceeds the second threshold that is larger than the first threshold.  FIG.  4    illustrates an example where three specific phases τ (specific phase τ 1  to specific phase τ 3 ) are specified. Note that the number of specific phases τ specified by the extraction unit  20 A is not limited to three. 
     Note that the length of each specific phase τ may be a fixed length or at least part of the plurality of specific phases τ may be different from each other. 
     In some cases, an evaluation function for evaluating a game status transition sequence is prepared. When a game is a drive game, the evaluation function evaluates, for example, lap time. In this case, the extraction unit  20 A may extract, as a specific phase τ, a range of evaluation values of the time-series set  42 A of first game statuses st shown in the first history information  30 A where each of the evaluation values is equal to or less than a specific value, in the time-series set  40 A of second game statuses St shown in the second history information  30 B. 
     Returning to  FIG.  2   , the description will be continued. The display control unit  20 B displays, on the display unit  24 , a display screen including a list of the specific phases τ extracted by the extraction unit  20 A. 
       FIG.  5    is a schematic diagram illustrating an example of a display screen  44 . The display screen  44  includes images showing specific phases τ extracted by the extraction unit  20 A.  FIG.  5    illustrates, as an example, images showing eight specific phases τ. 
     As described above, the input unit  22  is operated by the fourth player U 4 . The fourth player U 4  operates the input unit  22  to input a classification rule for clustering a plurality of specific phases τ into one or more clusters. 
     For example, the fourth player U 4  operates the input unit  22  to draw a frame line  46  so that specific phases τ belonging to the same cluster is accommodated in the same frame. By this drawing operation, the classification rule is input to cluster the specific phases τ arranged inside the same frame line  46 , as the specific phases τ belonging to the same cluster. 
     Furthermore, the fourth player U 4  operates the input unit  22  to assign at least one of a label  48  and priority  49  to each cluster. The label  48  is information indicating the name of each cluster. The priority  49  indicates priority for the first player U 1  to learn a specific phase τ belonging to a cluster to which the priority  49  is assigned.  FIG.  5    illustrates, as an example, the priority rank is indicated by the number of stars. 
     Note that methods of inputting the classification rule for clustering, inputting to the display screen  44 , and inputting the label  48  and priority  49  are not limited to the form illustrated in  FIG.  5   . 
     Returning to  FIG.  2   , the description will be continued. The classification unit  20 C classifies a plurality of specific phases τ into at least one or more cluster according to the classification rule specified by the fourth player U 4 . Note that the classification unit  20 C may classify the plurality of specific phases τ into at least one cluster according to a predetermined classification rule. A known classification rule is preferably used as the predetermined classification rule. For example, feature amounts of specific phases τ may be derived by a known method so that cluster specific phases τ having an approximate feature amount are clustered. Furthermore, the predetermined classification rule may be properly changed by an operation command or the like given by a player U. 
     The assignment unit  20 D assigns at least one of the label  48  and the priority  49  to a cluster in response to a command from the fourth player U 4 . Note that the classification unit  20 C may assign the label or priority according to the feature amount or the like of a specific phase τ. For example, the classification unit  20 C may store labels  48  and priority  49  corresponding to feature amounts in advance, read a label  48  and priority  49  corresponding to a feature amount of a specific phase τ, and then assign these labels  48  and priority  49 . 
     Next, the communication control unit  20 E will be described. The communication control unit  20 E transmits a specific phase list of specific phases τ extracted by the extraction unit  20 A to the information processing device  12  via the communication unit  26 . Note that the communication control unit  20 E may transmit, to the information processing device  12 , the specific phase list of specific phases τ, a result of the clustering, and at least one of the label  48  and the priority  49  that are assigned to the cluster. Referring to the assigned label  48  makes it easy to understand what meaning a group of the specific phases has, what kind of skill can be acquired by learning thereof, what attention is to be paid to during learning. Conversely, it is better to determine the label so that the above is achieved. The same applies to priority. 
     [Configuration of Information Processing Device According to First Embodiment] 
     Next, the information processing device  12  will be described. 
     The information processing device  12  includes a control unit  32 , a communication unit  34 , a storage unit  36 , a communication unit  37 , and a communication unit  38 . The communication unit  34 , the storage unit  36 , the communication unit  37 , the communication unit  38 , and the control unit  32  are connected so as to exchange data or signals. 
     The communication unit  34  is a communication interface that communicates with the extraction device  10 . The communication unit  37  is a communication interface that outputs a command signal from the input unit  16  to the control unit  32 . The storage unit  36  stores various information. The communication unit  38  is a communication interface that communicably connects the control unit  32  and the game device  14 . 
     The control unit  32  controls the information processing device  12 . The control unit  32  includes an acquisition unit  32 A, a determination unit  32 B, and an output control unit  32 C. 
     Part or all of the acquisition unit  32 A, the determination unit  32 B, and the output control unit  32 C may be achieved, for example, by causing a processing device such as a CPU to execute a program, that is, by using software, may be achieved by using hardware such as an IC, or may be achieved by using both of the software and the hardware. 
     The acquisition unit  32 A acquires a specific phase list of specific phases τ from the extraction device  10  via the communication unit  34 . As described above, the specific phase τ is a phase as a learning target for the first player U 1  who inputs an operation by using the input unit  16  to the game device  14  connected to the information processing device  12 . Note that the acquisition unit  32 A may acquire, from the extraction device  10 , the specific phase list of specific phases τ, a result of clustering, and at least one of a label  48  and priority  49  that are assigned to a cluster. 
     At the start of a game, the first player U 1  turns on the game device  14  to play a game and operates the input unit  16  to select a game program to be played. Then, the game device  14  starts execution of the game on the basis of the selected game program. The first player U 1  operates the input unit  16  to input a first command signal at, and a first game status st of the game executed on the game device  14  changes in response to the first command signal at. 
     The determination unit  32 B determines whether the current game status approaches a specific phase τ acquired by the acquisition unit  32 A. 
     For example, when the game is a car racing game, the determination unit  32 B determines that the current game status approaches the specific phase τ, when a difference between v coordinates (in some cases, also referred to as Frenet coordinates) of a course in the current game status and v coordinates of a course in the specific phase τ is equal to or less than a threshold. 
     Furthermore, the determination unit  32 B may determine that the current game status approaches the specific phase τ, when a minimum error between a prediction result of predicting a game status later than the current game status and a second game status St in the specific phase τ is equal to or less than a threshold. 
     Furthermore, the determination unit  32 B may determine that the current game status approaches the specific phase τ, in a case where there is a difference between the current game status and a second game status St that is provided at the first timing in a specific phase τ represented by a time-series set of second game statuses St and when a game status having the difference equal to or more than a predetermined distance is switched to a game status having the difference equal to or less than the predetermined distance. 
     Furthermore, for example, the determination unit  32 B may make the determination by determining whether the current game status is provided at timing earlier for a predetermined time than timing at which the current game status changes to a game status shown in the specific phase τ. 
     Furthermore, the determination unit  32 B may determine that the current game status approaches the specific phase τ when a signal indicating a second game status St in the target specific phase τ is received from outside. 
     When a game status approaches a specific phase τ, the output control unit  32 C outputs, to the game device  14 , guiding command information guiding to a reproduced game status where the specific phase τ is reproduced. In other words, the output control unit  32 C outputs the guiding command information to the game device  14  when the determination unit  32 B determines that the game status approaches the specific phase τ. 
       FIG.  6    is a graph illustrating an output of the guiding command information For example, it is assumed that a current game status C approaches the specific phase τ 3 . The specific phase τ 3  is an example of the specific phase τ. 
     The reproduced game status represents a second game status St shown in a specific phase τ. In other words, the reproduced game status represents a game status that became a factor causing a phase deviated from a second game status St achieved by an operation command given by the second player U 2  with a higher learning level, when the first player U 1  played the game in the past. 
     Specifically, the reproduced game status represents second game statuses St corresponding to one or more time points (timings) within a specific phase τ represented by a time-series set of second game statuses St. For example, the reproduced game status represents a second game status St at the starting point of a specific phase τ represented by a time-series set of second game statuses St. In other words, in the time-series set  40 A of second game statuses St of the second player U 2 , the reproduced game status represents the second game status St at a time point P where a distance to the time-series set  42 A of first game statuses st in the past of the first player U 1  is equal to or less than the first threshold. In this case, specifically, the reproduced game status where the specific phase τ 3  in  FIG.  6    is reproduced represents a second game status St at a time point P 3  in the specific phase τ 3 . In the present embodiment, as an example, the reproduced game status that represents a second game status St at the starting point of a specific phase τ represented by a time-series set of second game statuses St will be described. 
     Then, the output control unit  32 C outputs, to the game device  14 , the guiding command information for guiding (see an arrow  41  in  FIG.  6   ) the current game status C to the reproduced game status (in the example illustrated in  FIG.  6   , second game status St at the time point P 3  in the specific phase τ 3 ). 
     The guiding command information is preferably information including at least one of a correction command signal at′ and game status changing command information, the correction command signal at′ causing the current game status C to change in a direction approaching the reproduced game status is obtained by correcting the first command signal at for a game status received from the first player U 1 , and the game status changing command information changes the game status in a direction approaching the reproduced game status. 
     For example, when the current game status C approaches a specific phase τ, the output control unit  32 C corrects the first command signal at received from the input unit  16  before reaching the specific phase τ to the correction command signal at′ causing the current game status C to change in a direction the current game status C in a direction approaching a reproduced game status at a time point P, and outputs the corrected correction command signal to the game device  14 . 
     Therefore, when the current game status C approaches the specific phase τ, instead of the first command signal at in response to the operation command input to the input unit  16  by the first player U 1 , the correction command signal at′ for causing the current game status C to approach the reproduced game status is output to the game device  14 . 
     Furthermore, for example, when the current game status C approaches the specific phase τ, the output control unit  32 C may output the game status changing command information changing the current game status C in a direction approaching the reproduced game status, to the game device  14 . 
     As described above, when the current game status C approaches the reproduced game status, the output control unit  32 C of the game device  14  outputs, instead of the first command signal at received from the input unit  16  in response to an operation command given by the first player U 1 , the guiding command information including at least one of the correction command signal at′ obtained by correcting the first command signal at and the game status changing command information, to the game device  14 . 
     Therefore, when the current game status C approaches the specific phase τ as the learning target for the first player U 1 , the game device  14  provides a reproduced game status where the specific phase τ that first player U 1  needs to learn is reproduced. Therefore, it is easy to train the first player U 1  for the specific phase τ where a past history of first game statuses st is quite different from a history of second game statuses St achieved by the second player U 2  with a higher learning level. 
     Note that sudden change of the game status to the reproduced game status may cause the first player U 1  to feel uncomfortable. Therefore, the output control unit  32 C preferably outputs, to the game device  14 , the guiding command information stepwisely or continuously guiding the current game status C to the reproduced game status. 
     Specifically, the output control unit  32 C gradually reduces an error to zero over n steps, from the current game status C to the reproduced game status. Note that n is an integer of 1 or more. 
     To achieve this, for example, the following configuration can be provided. The output control unit  32 C calculates a target first game status (st+k)+(S−(st+k))/(n−k+1) in each time step k (k=1, 2, . . . , and n) so that an error between a first game status st and a target reproduced game status S is gradually reduced to 0 over n steps. Note that S represents a reproduced game status. Furthermore, k represents an index indicating each step of the n steps until the reproduced game status which is the final goal is achieved. 
     Then, the output control unit  32 C determines guiding command information to be output to the game device  14  in each step by calculating a correction command signal at′ that achieves a target first game status in each step. In other words, the output control unit  32 C replaces a first command signal at received from the input unit  16  in response to an operation command given by the first player U 1 , with a correction command signal at′ and outputs the correction command signal at′ as the guiding command information. 
     Note that, in each step, the output control unit  32 C may perform feedback control to the target first game status corresponding to each step and output, to the game device  14 , the guiding command information guiding the current game status C to the reproduced game status stepwisely or continuously. The feedback control preferably employs a known proportional-integral-differential (PID) control or the like. 
     Note that the output control unit  32 C designates a specific phase τ belonging to a cluster having a higher priority  49  in priority to a specific phase τ belonging to a cluster having a lower priority  49  and outputs the guiding command information to the game device  14  when the current game status C approaches the designated specific phase τ. 
     In addition, at the beginning of a game, the game device  14  may display, on the output unit  18 , a display screen (e.g., the display screen  44  illustrated in  FIG.  5   ) including a list of specific phases τ included in the game, a cluster to which the specific phase τ belongs, a label  48  and priority  49  assigned to the cluster. 
     Displaying the display screen on the output unit  18  by the game device  14  makes it easy to show the first player U 1  whether a specific phase τ included in a game to be executed has what kind of content to be learned and what kind of priority. 
     Note that when the output control unit  32 C determines that the game status has reached the specific phase τ, the output control unit  32 C finishes output of the guiding command information to the game device  14 . In other words, the output control unit  32 C starts output of the guiding command information to the game device  14  when the current game status C approaches the specific phase τ, and finishes output of the guiding command information to the game device  14  when the current game status C reaches a second game status St (reproduced game status in the present embodiment) at the starting point of the specific phase τ. 
     Note that the output control unit  32 C may finish output of the guiding command information to the game device  14  when a predetermined time has passed after it is determined that the current game status C approaches the specific phase τ. For example, the output control unit  32 C may finish the output of the guiding command information to the game device  14 , after the steps of the specific phase τ have passed, the steps, the number of which is obtained by adding a predetermined number of steps to the steps of the specific phase τ, have passed, or the steps, the number of which is a constant multiple of the number of steps of the specific phase τ, have passed after it is determined that the current game status C approaches the specific phase τ. 
     Furthermore, when all of the time-series sets of game statuses after entering the specific phase τ are away from the current game status C by a distance of a threshold or more, the output control unit  32 C may determine that the guiding is impossible so that the output of the guiding command information to the game device  14  is stopped. For this distance, a value derived from a function used for the distances of the first threshold and the second threshold is preferably used. 
     Furthermore, the output control unit  32 C may stop the output of the guiding command information to the game device  14  when the game status has a second game status St at the end point of the specific phase τ. 
     [Procedure of Extraction Processing According to First Embodiment] 
     Next, an example of a procedure of extraction processing performed by the extraction device  10  will be described. 
       FIG.  7    is a flowchart illustrating an example of the procedure of extraction processing performed by the extraction device  10 . 
     First, the extraction unit  20 A reads the first history information  30 A and the second history information  30 B from the storage unit  30  (Step S 100 ). 
     Next, the extraction unit  20 A extracts specific phases τ on the basis of the first history information  30 A and the second history information  30 B read in Step  100  (Step S 102 ). 
     Next, the display control unit  20 B displays a display screen including a list of the specific phases τ extracted in Step  102 , on the display unit  24  (Step S 104 ). The classification unit  20 C repeats the negative determination until it is determined that a classification rule for clustering is received from the input unit  22  (Step S 106 : No). Then, if the classification rule is received (Step S 106 : Yes), the classification unit  20 C clusters the specific phases τ extracted in Step S 102  on the basis of the received classification rule (Step S 108 ). 
     Next, the assignment unit  20 D repeats the negative determination until it is determined that labels  48  for clusters are received from the input unit  22  (Step S 110 : No). If the labels  48  are received (Step S 110 : Yes), the assignment unit  20 D assigns the received labels  48  to the corresponding clusters (Step S 112 ). 
     Next, the assignment unit  20 D repeats the negative determination until it is determined that priority  49  for the clusters is received from the input unit  22  (Step S 114 : No). If the priority  49  is received (Step S 114 : Yes), the assignment unit  20 D assigns the received priority  49  to the corresponding clusters (Step S 116 ). 
     Next, the communication control unit  20 E transmits a specific phase list of the specific phases τ extracted in Step S 102  to the information processing device  12  via the communication unit  26  (Step S 118 ). Note that the communication control unit  20 E may transmit, to the information processing device  12 , the specific phase list of the specific phases τ, a result of the clustering performed in Step S 108 , and at least one of the labels  48  and the priority  49  that are assigned to the clusters in Step S 112  and Step S 116 . Then, this routine is finished. 
     [Procedure of Information Processing According to First Embodiment] 
     Next, an example of a procedure of information processing performed by the information processing device  12  will be described. 
       FIG.  8    is a flowchart illustrating an example of the procedure of information processing performed by the information processing device  12 . 
     First, the acquisition unit  32 A of the information processing device  12  determines whether a game start command has been received from the input unit  16  (Step S 200 ). If a negative determination is made in Step S 200  (Step S 200 : No), this routine is finished. On the other hand, if an affirmative determination is made in Step S 200  (Step S 200 : Yes), the process proceeds to Step S 202 . 
     In Step S 202 , the acquisition unit  32 A acquires a specific phase list of specific phases τ from the extraction device  10  via the communication unit  34  (Step S 202 ). Note that the acquisition unit  32 A may acquire, from the extraction device  10 , the specific phase list of specific phases τ, a result of clustering, and at least one of a label  48  and priority  49  that are assigned to a cluster. 
     Next, the acquisition unit  32 A outputs the game start command received in Step S 200  to the game device  14  (Step S 204 ). 
     Then, if receiving a first command signal at from the input unit  16 , the output control unit  32 C outputs the first command signal at to the game device  14  via the communication unit  38  (Step S 206 ). The game device  14  changes a game status according to the first command signal at. This process makes the game progress according to an operation command from the first player U 1 . 
     Next, the determination unit  32 B determines whether the current game status C has approached the specific phase τ acquired in Step S 202  (Step S 208 ). If a negative determination is made in Step S 208  (Step S 208 : No), the process proceeds to Step S 214  which is described later. If an affirmative determination is made in Step S 208  (Step S 208 : Yes), the process proceeds to Step S 210 . 
     In Step S 210 , the output control unit  32 C outputs, to the game device  14 , guiding command information guiding to a reproduced game status where a specific phase τ is reproduced, for the specific phase τ to which the current game status C is determined to have approached in Step S 208  (Step S 210 ). 
     Next, the output control unit  32 C determines whether the current game status C reaches the first timing of the specific phase τ to which the current game status C is determined to have approached in Step S 208  (Step S 212 ). If a negative determination is made in Step S 212  (Step S 212 : No), the process returns to Step S 210  described above. On the other hand, if an affirmative determination is made in Step S 212  (Step S 212 : Yes), the process proceeds to Step S 214 . 
     In the processing of Steps S 206  to S 212 , when the current game status C of the running game approaches the specific phase τ, the game device  14  receives the guiding command information guiding to the reproduced game status of the specific phase τ and changes the game status to a second game status St at the first time point P of the specific phase τ stepwisely or continuously. 
     Next, the acquisition unit  32 A determines whether a game end command has been received from the input unit  16  (Step S 214 ). If a negative determination is made in Step S 214  (Step S 214 : No), the process returns to Step S 206  described above. Therefore, when entering the specific phase τ, the output control unit  32 C directly outputs the first command signal at received from the input unit  16  to the game device  14  via the communication unit  38  (Step S 206 ). In other words, when entering the specific phase τ, the output control unit  32 C outputs no guiding command information to the game device  14 . 
     On the other hand, if an affirmative determination is made in Step S 214  (Step S 214 : Yes), the process proceeds to Step S 216 . 
     In Step S 216 , the output control unit  32 C outputs the game end command to the game device  14  via the communication unit  38  (Step S 216 ), and this routine is finished. 
     As described above, the information processing device  12  according to the present embodiment includes the output control unit  32 C. When a game status approaches a specific phase τ, the output control unit  32 C outputs, to the game device  14 , guiding command information guiding to a reproduced game status where the specific phase τ is reproduced. 
     Incidentally, training content provided for acquire a technique step by step has been conventionally prepared to improve the learning level of a player U. For example, in a drive game, separate training content, such as a method for smooth acceleration or a method for entering a corner has been separately prepared. However, the training content is uniform, and it has been difficult to effectively support improvement in learning level. Furthermore, a training environment is merely provided to the player U and may lack in game experience and entertainment for the player U. In other words, it has been difficult for the conventional content to effectively support the improvement in learning level. 
     On the other hand, in the present embodiment, when a game status approaches the specific phase τ, the output control unit  32 C outputs, to the game device  14 , the guiding command information guiding to the reproduced game status where the specific phase τ is reproduced. 
     Therefore, when a game status achieved by the game device  14  approaches a specific phase τ, the game status is guided to a reproduced game status where the specific phase τ is reproduced. Therefore, the player U can be naturally trained in the specific phase τ. 
     Thus, the information processing device  12  according to the present embodiment can effectively support the improvement in game learning level. 
     Furthermore, the player U can be naturally trained for the specific phase τ, and thereby the information processing device  12  according to the present embodiment can improve the game experience and entertainment of the player U, in addition to the above effects. 
     Furthermore, the extraction unit  20 A of the extraction device  10  extracts a specific phase τ of a game on the basis of the first history information  30 A indicating the time-series set  42 A of first game statuses st of the first player U 1  and the second history information  30 B indicating the time-series set  40 A of second game statuses St of the second player U 2  with a higher learning level than the first player U 1 . 
     Therefore, the extraction unit  20 A is capable of accurately extracting a specific phase τ that needs to be learned by the first player U 1 . Furthermore, the information processing device  12  uses the specific phase τ extracted by the extraction unit  20 A to output, to the game device  14 , the guiding command information guiding to a reproduced game status where a specific phase τ corresponding to the level of the first player U 1  is reproduced. 
     Therefore, the information processing device  12  according to the present embodiment can support the improvement in learning level according to the level of the first player U 1 , in addition to the above effects. 
     Furthermore, in the present embodiment, the output control unit  32 C outputs, to the game device  14 , guiding command information that stepwisely or continuously guides the game status toward the reproduced game status. Therefore, the guiding command information is configured to suppress rapid change of the game status, and a player U can be naturally trained for a specific phase τ without causing the player U to feel a sense of discomfort. 
     Furthermore, use of a phase as the learning target for first player U 1  as the specific phase τ makes it possible for the information processing device  12  to support the improvement in learning level according to the level of the first player U 1 , in addition to the above effects. 
     Furthermore, in a time-series set of second game statuses of the second player U 2  with a higher learning level than the first player U 1 , the specific phase τ is a phase ranging from a time point P where the distance to a time-series set of first game statuses st in the past of the first player U 1  is equal to or less than the first threshold to a time point P′ where the distance exceeds the second threshold that is larger than the first threshold. Therefore, when the first player U 1  has played a game in the past, the information processing device  12  is configured to use, as a specific phase τ, a phase that is deviated from a second game status St achieved by a second command signal from the second player U 2  with a higher learning level. Therefore, the information processing device  12  is capable of accurately identifying as the specific phase τ a phase that can be learned better by the first player U 1  and using the phase to support the improvement in learning level, in addition to the above effects. 
     Furthermore, the output control unit  32 C outputs, to the game device  14 , the guiding command information including at least one of a correction command signal at′ and game status changing command information, the correction command signal at′ causing the game status to change in a direction approaching the reproduced game status is obtained by correcting the first command signal at received from the first player U 1 , and the game status changing command information changes the game status in a direction approaching the reproduced game status. 
     Therefore, when the game status approaches a specific phase τ, the first command signal at input by the first player U 1  by operating the input unit  16  is corrected to the correction command signal at′ by the information processing device  12  and output to the game device  14 . Therefore, the first player U 1  is naturally guided to the reproduced game status by normally operating the input unit  16 . 
     Therefore, the information processing device  12  according to the present embodiment can naturally support the improvement in learning level, in addition to the above effects. 
     Furthermore, the classification unit  20 C of the extraction device  10  classifies a plurality of specific phases τ into at least one cluster according to a classification rule specified by the fourth player U 4 . The assignment unit  20 D assigns at least one of the label  48  and the priority  49  to a cluster in response to a command from the fourth player U 4 . 
     Therefore, the fourth player U 4 , such as an administrator, different from the first player U 1  is capable of performing clustering or assigning a label  48  and priority  49  according to the first player U 1 . 
     Furthermore, as described above, at the beginning of a game, the game device  14  may display, on the output unit  18 , a display screen (e.g., the display screen  44  illustrated in  FIG.  5   ) including a list of specific phases τ included in a game, a cluster to which a specific phase τ belongs, a label  48  and priority  49  assigned to the cluster. 
     Displaying the display screen on the output unit  18  by the game device  14  makes it easy to show a player U whether a specific phase τ included in a game to be executed has what kind of content to be learned and what kind of priority. 
     Furthermore, when a game executed in the game device  14  is content in which the game is advanced by moving a character or an avatar in the game, displaying the display screen makes it possible to readily provide a learning status of the character or avatar in the game to a player U. Furthermore, the information processing device  12  can support efficient learning of the character or avatar in the game to efficiently grow the character or avatar in the game or improve the game experience of a player U. 
     Modification of First Embodiment 
     Note that in the above embodiment, an example where the player U is a person has been described. However, the player U may be a computer that outputs, to the game device  14 , a command signal for shifting a game status according to the game status. 
       FIG.  9    is a schematic diagram illustrating an example of an information processing system  1 A according to the present modification. 
     The information processing system  1 A includes the extraction device  10 , the information processing device  12 , the game device  14 , the output unit  18 , and a computer U′. The extraction device  10 , the information processing device  12 , the game device  14 , and the output unit  18  are configured similarly to those in the first embodiment. 
     In the present modification, the computer U′ is provided instead of the input unit  16 . The computer U′ is an example of the first player U 1 . 
     The computer U′ is a device that inputs a first command signal for a game status achieved on the game device  14 . The computer U′ includes, for example, a learning device or the like that learns an optimum command signal or the like to be output for a game status. 
     As described above, the player U is not limited to a person and may be a computer. When the player U is the computer, the game status is acquired by communication via the information processing device  12 , and thus, the output unit  18  is not always necessary. 
     Note that, also in the information processing system  1 A, the extraction device  10  and the information processing device  12  perform processing similar to that in the first embodiment. 
     Therefore, even when the player U is the computer U′, it is possible to effectively support the improvement in game learning level. 
     Here, when the computer U′ is a device that learns an optimum command signal or the like output for a game status, a major factor that influences the learning performance is data used for learning. In particular, it is known that particularly large amount of data is required in reinforcement learning such as a game. This is because the game includes a plurality of types of classification, a plurality of types of identification or prediction, and a complicated task as compared with a regression problem. 
     As a conventional method of collecting a large amount of data, there is known a method of collecting user&#39;s game log to be used for learning. However, in a conventional method, it has been difficult to collect all game log of various users and under various situations, and thus, it has been difficult to learn an optimum command signal. 
     Furthermore, in a conventional method, it has been difficult to learn an optimum command signal or the like while avoiding unnatural transition of a game status that impairs the game experience of the player U and entertainment and while naturally reproducing a phase to be learned by the player U. 
     On the other hand, when a game status approaches a specific phase τ, the information processing device  12  of the information processing system  1 A according to the present modification outputs, to the game device  14 , the guiding command information guiding to the reproduced game status where the specific phase τ is reproduced. Therefore, the computer U′ as the first player U 1  can naturally learn the specific phase τ. 
     Therefore, even when the player U is the computer U′, the information processing device  12  according to the present embodiment can effectively support the improvement in game learning level. 
     Second Embodiment 
     In the first embodiment, the information processing device  12  outputs the guiding command information to the game device  14  when the current game status C approaches a specific phase τ. Therefore, when the current game status C of a running game approaches the specific phase τ, the game device  14  changes the game status toward a second game status St at the first time point P of the specific phase τ stepwisely or continuously. 
     On the other hand, in the present embodiment, a mode will be described in which a third command signal in response to an operation command given by the third player U 3  with a higher learning level than the first player U 1  is output to the game device  14 , for the duration of a specific phase τ. 
     [Configuration of Information Processing System According to Second Embodiment] 
       FIG.  10    is a schematic diagram illustrating an example of an information processing system  1 B according to the present embodiment. 
     The information processing system  1 B includes the extraction device  10 , an information processing device  12 B, and a game device  14 . The output unit  18  and an output unit  19  are connected to the game device  14 . Furthermore, the input unit  16  and an input unit  17  are connected to the game device  14  via the information processing device  12 B in a wired or wireless manner. The extraction device  10  and the game device  14  are communicably connected via a network N. The extraction device  10  and the information processing device  12 B are directly connected via a connection cable so as to be communicated with each other. The extraction device  10  and the information processing device  12 B may be wirelessly connected. Furthermore, the extraction device  10  and the information processing device  12 B may be communicably connected via the network N. 
     The extraction device  10 , the game device  14 , the input unit  16 , and the output unit  18  are configured similarly to those in the first embodiment. 
     The input unit  17  is an input interface device for the third player U 3  to input an operation to the game device  14 . The third player U 3  is a player U with a higher game learning level than the first player U 1 . The third player U 3  may be a player U with a lower game learning level than the second player U 2 . 
     The input unit  17  outputs, to the information processing device  12 , a third command signal in response to an operation command given by the third player U 3 . The input unit  17  includes a controller, keyboard, touch panel, pointing device, mouse, input button, or the like. The output unit  19  is a display that displays a game image from the game device  14 . The output unit  19  is a display for visual confirmation by the third player U 3  during a game. The output unit  19  includes, for example, a known LCD or organic EL. The output unit  19  may further have a speaker function that outputs sound, in addition to an image display function. 
     The information processing device  12 B outputs various information to the game device  14 , in a manner similar to the information processing device  12  according to the first embodiment 
     [Configuration of Information Processing Device According to Second Embodiment] 
       FIG.  2    is an example of a functional block diagram illustrating the extraction device  10  and the information processing device  12 B of the information processing system  1 B. The configuration of the extraction device  10  is configured similarly to those in the first embodiment. 
     The information processing device  12 B includes a control unit  33 , the communication unit  34 , the storage unit  36 , the communication unit  37 , and the communication unit  38 . The information processing device  12 B has a configuration similar to that of the information processing device  12  according to the first embodiment, except that the information processing device  12 B includes the control unit  33  instead of the control unit  32  and that the communication unit  37  receives a command signal from the input unit  16  and the input unit  17 . 
     The control unit  33  controls the information processing device  12 B. The control unit  33  includes the acquisition unit  32 A, the determination unit  32 B, and an output control unit  33 C. The acquisition unit  32 A and the determination unit  32 B are similar to those of the information processing device  12  according to the first embodiment. 
     When a game status approaches a specific phase τ, the output control unit  33 C outputs, to the game device  14 , the guiding command information guiding to the reproduced game status where the specific phase τ is reproduced, in a manner similar to the output control unit  32 C according to the first embodiment. 
     Furthermore, In the present embodiment, for the duration of the specific phase τ, the output control unit  33 C outputs, to the game device  14 , the third command signal received from the third player U 3  with a higher learning level than the first player, instead of a first command signal at received from the first player U 1 . 
     Therefore, in the present embodiment, when the current game status C approaches the specific phase τ, instead of the first command signal at in response to an operation command input to the input unit  16  by the first player U 1 , a correction command signal at′ for causing the current game status C to approach the game status where the specific phase τ is reproduced is output to the game device  14 . 
     Then, when entering the specific phase τ, for the duration of the specific phase τ, the output control unit  32 C does not receive the first command signal at in response to an operation command given by the first player U 1  from the input unit  16 , but receives the third command signal in response to an operation command given by the third player U 3  from the input unit  17  and outputs the third command signal to the game device  14 . 
     Therefore, in the present embodiment, the first player U 1  visually confirms the output unit  18  for the duration of the specific phase τ, and it is possible to confirm the shift of the game status achieved in response to the third command signal of the second player U 2  with a higher learning level than the first player U 1 . 
     Note that the output control unit  32 C may store a time-series set of third operation commands to the specific phase τ that are given by the third player U 3 , in advance. Then, for the duration of the specific phase τ, the output control unit  32 C may not receive, from the input unit  16 , the first command signal at in response to an operation command given by the first player U 1  but may sequentially output the stored time-series set of the third command signals to the game device  14 . 
     Note that the input unit  17  is not limited to the configuration of direct connection to the information processing device  12 B. The input unit  17  may be connected to the information processing device  12 B via the network N. The output unit  19  may be connected to the game device  14  via the network N. 
     [Procedure of Information Processing According to Second Embodiment] 
     Next, an example of a procedure of information processing performed by the information processing device  12 B will be described. 
       FIG.  11    is a flowchart illustrating an example of the procedure of information processing performed by the information processing device  12 B. 
     First, the acquisition unit  32 A of the information processing device  12 B determines whether a game start command has been received from the input unit  16  (Step S 300 ). If a negative determination is made in Step S 300  (Step S 300 : No), this routine is finished. On the other hand, if an affirmative determination is made in Step S 300  (Step S 300 : Yes), the process proceeds to Step S 302 . 
     In Step S 302 , the acquisition unit  32 A acquires a specific phase list of specific phases τ from the extraction device  10  via the communication unit  34  (Step S 302 ). Next, the acquisition unit  32 A outputs the game start command received in Step S 300  to the game device  14  (Step S 304 ). 
     Then, if receiving a first command signal at from the input unit  16 , the output control unit  33 C outputs the first command signal at to the game device  14  (Step S 306 ). The game device  14  changes a game status according to the first command signal at. This process makes the game progress according to an operation command from the first player U 1 . 
     Next, the determination unit  32 B determines whether the current game status C has approached the specific phase τ acquired in Step S 302  (Step S 308 ). If a negative determination is made in Step S 308  (Step S 308 : No), the process proceeds to Step S 318  which is described later. If an affirmative determination is made in Step S 308  (Step S 308 : Yes), the process proceeds to Step S 310 . 
     In Step S 310 , the output control unit  33 C outputs, to the game device  14 , guiding command information guiding to a reproduced game status where a specific phase τ is reproduced, for the specific phase τ to which the current game status C is determined to have approached in Step S 308  (Step S 310 ). 
     Next, the output control unit  33 C determines whether the current game status C reaches the first timing of the specific phase τ to which the current game status C is determined to have approached in Step S 308  (Step S 312 ). If a negative determination is made in Step S 312  (Step S 312 : No), the process returns to Step S 310  described above. On the other hand, if an affirmative determination is made in Step S 312  (Step S 312 : Yes), the process proceeds to Step S 314 . 
     In Step S 314 , the output control unit  33 C outputs a third command signal from the third player U 3 , to the game device  14  (Step S 314 ). Next, the output control unit  33 C determines whether the specific phase τ ends (Step S 316 ). If a negative determination is made in Step S 316  (Step S 316 : No), the process returns to Step S 314  described above. On the other hand, if an affirmative determination is made in Step S 316  (Step S 316 : Yes), the process proceeds to Step S 318 . 
     In the processing of Steps S 314  to S 316 , for the duration of the specific phase τ, the third command signal received from the third player U 3  with a higher learning level than the first player, instead of a first command signal at received from the first player U 1  is output to the game device  14 . 
     Next, the acquisition unit  32 A determines whether a game end command has been received from the input unit  16  (Step S 318 ). If a negative determination is made in Step S 318  (Step S 318 : No), the process returns to Step S 306  described above. Therefore, when the specific phase τ has passed, the output control unit  33 C directly outputs the first command signal at received from the input unit  16  to the game device  14  via the communication unit  38  (Step S 306 ). 
     On the other hand, if an affirmative determination is made in Step S 318  (Step S 318 : Yes), the process proceeds to Step S 320 . 
     In Step S 320 , the output control unit  33 C outputs the game end command to the game device  14  via the communication unit  38  (Step S 320 ), and this routine is finished. 
     As described above, for the duration of the specific phase τ, the information processing device  12 B according to the present embodiment outputs, to the game device  14 , the third command signal received from the third player U 3  with a higher learning level than the first player U 1 , instead of a first command signal at received from the first player U 1 . 
     Therefore, for the duration of the specific phase τ, the information processing device  12 B according to the present embodiment can provide the first player U 1  the shift of the game status achieved in response to the third command signal of the second player U 2  with a higher learning level than the first player U 1 . In other words, the information processing device  12 B can readily provide the first player U 1  the shift of the game status as a model. 
     Therefore, the information processing device  12 B according to the present embodiment can further effectively support the improvement in learning level, in addition to the effects of the first embodiment described above. 
     Note that, in the configuration of  FIG.  10   , any one of the first player U 1  and the third player U 3  may be the computer U′ (see the third embodiment). It is assumed that the first player U 1  is a person and the third player U 3  is the computer U′. In this case, the computer U′ that has learned the game more than the first player U 1  can shows a model for the game to the first player U 1 , thereby supporting the improvement in learning level of the first player U 1 . On the other hand, it is assumed that the first player U 1  is the computer U′ and the third player U 3  is a person. In this case, it is possible for a person to support the improvement in learning level of the computer U′ that learns game operations. 
     Third Embodiment 
     In the present embodiment, a mode will be described in which a third command signal input in response to an operation command given by the third player U 3  with a higher learning level than the first player U 1  is output to the first player U 1  being the computer U′, for the duration of a specific phase τ. 
     [Configuration of Information Processing System According to Third Embodiment] 
       FIG.  12    is a schematic diagram illustrating an example of an information processing system  1 C according to the present embodiment. 
     The information processing system  1 C includes the extraction device  10 , an information processing device  12 C, a first game device  14 A, and a third game device  14 C. The extraction device  10 , the first game device  14 A, the third game device  14 C, and the information processing device  12 C are connected via the network N. At least two or more of the extraction device  10 , the first game device  14 A, the third game device  14 C, and the information processing device  12 C may be directly connected in a wired or wireless manner. 
     The first game device  14 A is a game device  14  that receives a first command signal from the first player U 1 . An output unit  18 A and the computer U′ are connected to the first game device  14 A. The output unit  18 A is a display that displays a game image from the first game device  14 A. Note that the output unit  18 A is configured to be omitted as in the above embodiment. 
     In the present embodiment, as in the modification, a description is made of an example where the first player U 1  is the computer U′. The computer U′ is a device that inputs a first command signal for a game status achieved on the first game device  14 A. As described in the modification, the computer U′ includes a learning device or the like that searches for an optimum command signal or the like for a game status. In the present embodiment, the first player U 1  being the computer U′ is connected to the first game device  14 A and is also connected via the network N to the third game device  14 C and the information processing device  12 C. 
     The third game device  14 C is a game device  14  that advances a game in response to a third command signal from the third player U 3 . An output unit  18 C and the information processing device  12 C are connected to the third game device  14 C. The output unit  18 C is a display that displays a game image from the third game device  14 C. 
     An input unit  16 C is connected to the third game device  14 C via the information processing device  12 C. The input unit  16 C is an input interface device for the third player U 3  to input an operation to the third game device  14 C. The input unit  16 C outputs to the third game device  14 C the third command signal in response to the operation command given by the third player U 3 . The input unit  16 C includes a controller, keyboard, touch panel, pointing device, mouse, input button, or the like. 
     The information processing device  12 C outputs various information to the third game device  14 C. Furthermore, in the present embodiment, the information processing device  12 C outputs various information to the first player U 1  via the third game device  14 C and the network N. 
     [Configuration of Information Processing Device According to Third Embodiment] 
       FIG.  13    is an example of a functional block diagram illustrating the extraction device  10  and the information processing device  12 C of the information processing system  1 C. The configuration of the extraction device  10  is configured similarly to those in the first embodiment. 
     The information processing device  12 C includes a control unit  35 , the communication unit  34 , a storage unit  36 , the communication unit  37 , the communication unit  38 , and a communication unit  39 . The communication unit  34  and the storage unit  36  are configured similarly to those in the first embodiment. In the present embodiment, the communication unit  37  receives the third command signal from the input unit  16 C. The communication unit  38  is a communication interface for communicating with the third game device  14 C. The communication unit  39  is a communication interface that communicates with the first game device  14 A and the computer U′ being the first player U 1 , via the network N. 
     The control unit  35  controls the information processing device  12 C. The control unit  35  includes an acquisition unit  32 A, a determination unit  32 B, and an output control unit  35 C. The acquisition unit  32 A and the determination unit  32 B are similar to those of the information processing device  12  according to the first embodiment. 
     When a game status approaches a specific phase τ, the output control unit  35 C outputs, to the game device  14 , guiding command information guiding to a reproduced game status where the specific phase τ is reproduced, in a manner similar to the output control unit  32 C according to the first embodiment. However, the output control unit  35 C outputs the guiding command information to the third game device  14 C. 
     In other words, in the present embodiment, when the game status of the third game device  14 C that receives the third command signal from the third player U 3  approaches the specific phase τ as the learning target for the first player U 1 , the output control unit  35 C outputs the guiding command information to the third game device  14 C as the game device  14 . 
     Then, the output control unit  35 C outputs to the first player U 1  being the computer U′ a time-series set of third command signals received for the duration of the specific phase τ from the third player U 3 . 
     Therefore, the first player U 1  is capable of learning the third command signals received from the third player U 3  with a higher game learning level than the first player U 1 , as command signals to be output to the first game device  14 A, in the specific phase τ being the learning target for the first player U 1 . 
     Note that the output control unit  35 C may output the time-series set of third command signals received for the duration of the specific phase τ from the third player U 3 , to the first player U 1  being the computer U′, via the third game device  14 C. 
     Furthermore, the output control unit  35 C may output to the first player U 1  being the computer U′, history information about games played by the third player U 3  including the duration of the specific phase τ. In this configuration, the output control unit  35 C preferably outputs history information including the time-series set of third command signals from the third player U 3  and a time-series set of game statuses changed by the third command signals, to the first player U 1  being the computer U′. 
     For the duration of the specific phase τ, the first player U 1  being the computer U′ preferably outputs the third command signals from the third player U 3  to the first game device  14 A so as to learn optimum command signals for a game status. 
     [Procedure of Information Processing According to Third Embodiment] 
     Next, an example of a procedure of information processing performed by the information processing device  12 C will be described. 
       FIG.  14    is a flowchart illustrating an example of the procedure of information processing performed by the information processing device  12 C. 
     First, the acquisition unit  32 A of the information processing device  12 C determines whether a game start command has been received from the input unit  16 C (Step S 400 ). If a negative determination is made in Step S 400  (Step S 400 : No), this routine is finished. On the other hand, if an affirmative determination is made in Step S 400  (Step S 400 : Yes), the process proceeds to Step S 402 . 
     In Step S 402 , the acquisition unit  32 A acquires a specific phase list of specific phases τ from the extraction device  10  via the communication unit  34  (Step S 402 ). Next, the acquisition unit  32 A outputs the game start command received in Step S 400  to the third game device  14 C (Step S 404 ). 
     Then, when receiving a third command signal from the input unit  16 C, the output control unit  35 C outputs the third command signal to the third game device  14 C (Step S 406 ), and the third game device  14 C changes a game status according to the third command signal. This process makes the game progress according to an operation command from the third player U 3 . 
     Next, the determination unit  32 B determines whether the current game status C has approached the specific phase τ acquired in Step S 402  (Step S 408 ). If a negative determination is made in Step S 408  (Step S 408 : No), the process proceeds to Step S 418  which is described later. If an affirmative determination is made in Step S 408  (Step S 408 : Yes), the process proceeds to Step S 410 . 
     In Step S 410 , the output control unit  35 C outputs, to the third game device  14 C, guiding command information guiding to a reproduced game status where a specific phase τ is reproduced, for the specific phase τ to which the current game status C is determined to have approached in Step S 408  (Step S 410 ). 
     Next, the output control unit  35 C determines whether the current game status C reaches the first timing of the specific phase τ to which the current game status C is determined to have approached in Step S 408  (Step S 412 ). If a negative determination is made in Step S 412  (Step S 412 : No), the process returns to Step S 410  described above. On the other hand, if an affirmative determination is made in Step S 412  (Step S 412 : Yes), the process proceeds to Step S 414 . 
     In Step S 414 , the output control unit  35 C outputs the third command signal from the third player U 3 , to the third game device  14 C and the first player U 1  being the computer U′ (Step S 414 ). 
     Next, the output control unit  35 C determines whether the specific phase τ ends (Step S 416 ). If a negative determination is made in Step S 416  (Step S 416 : No), the process returns to Step S 414  described above. On the other hand, if an affirmative determination is made in Step S 416  (Step S 416 : Yes), the process proceeds to Step S 418 . 
     In the processing of Steps S 414  to S 416 , for the duration of the specific phase τ, the third command signal received from the third player U 3  with a higher learning level than the first player U 1  is output to the third game device  14 C and the first player U 1  being the computer U′. 
     Next, the acquisition unit  32 A determines whether a game end command has been received from the input unit  16 C (Step S 418 ). If a negative determination is made in Step S 418  (Step S 418 : No), the process returns to Step S 406  described above. 
     On the other hand, if an affirmative determination is made in Step S 418  (Step S 418 : Yes), the process proceeds to Step S 420 . In Step S 420 , the output control unit  35 C outputs the game end command to the third game device  14 C via the communication unit  38  (Step S 420 ), and this routine is finished. 
     As described above, when the game status of the third game device  14 C that receives the third command signal from the third player U 3  with a higher learning level than the first player U 1  approaches the specific phase τ, the output control unit  35 C of the information processing device  12 C according to the present embodiment outputs the guiding command information to the third game device  14 C. Then, the output control unit  35 C outputs to the first player U 1 , as the computer U′, a time-series set of third command signals received for the duration of the specific phase τ from the third player U 3 . 
     As described above, the information processing device  12 C according to the present embodiment provides the specific phase τ as the learning target for the first player U 1 , to the third player U 3  with a higher learning level than the first player U 1  and outputs the time-series set of third command signals in response to commands given by the third player U 3  in the specific phase τ to the first player U 1  as the computer U′. 
     Therefore, the information processing device  12 C according to the present embodiment can reduce a learning time for the computer U′ to learn an optimum command signal for the game status by, in addition to the effects of the above embodiment. 
     Fourth Embodiment 
     In the present embodiment, a mode will be described in which the extraction device  10  uses a training phase as a specific phase τ corresponding to each of one or more players U to further extract another specific phase τ not extracted from the first history information  30 A of the first player U 1 . 
     [Configuration of Extraction Device According to Fourth Embodiment] 
       FIG.  15    is an example of a functional block diagram illustrating an extraction device  11  and the information processing device  12  included in an information processing system  1 D according to the present embodiment. The information processing device  12  is configured similarly to those in the first embodiment. 
     The extraction device  11  extracts a specific phase τ of a game, in a manner similar to the extraction device  10  according to the first embodiment. 
     The extraction device  11  includes a control unit  21 , the UI unit  23 , the communication unit  26 , a storage unit  31 , and the communication unit  28 . The UI unit  23 , the communication unit  26 , and the communication unit  28  are configured similarly to those in the first embodiment. 
     The storage unit  31  stores various information. In the present embodiment, the storage unit  30  stores the first history information  30 A, the second history information  30 B, a player history information  30 C, and a specific phase list  30 D. 
     The first history information  30 A and the second history information  30 B are configured similarly to those in the first embodiment. In other words, the first history information  30 A is information indicating a history of games played by the first player U 1 . The second history information  30 B is information indicating a history of games played by the second player U 2  with a higher learning level of games than the first player U 1 . 
     The player history information  30 C is information indicating a history of games played by a player U. In association with identification information about each of the one or more players U, the player history information  30 C of the players U identified by the identification information is stored in the storage unit  31 . Note that the player history information  30 C has a data structure similar to the first history information  30 A and the second history information  30 B (see  FIG.  3   ). 
     The specific phase list  30 D is a list of specific phases τ extracted for each of the one or more players U. In association with the identification information about each of the one or more players U, the specific phase lists  30 D for the players U identified by the identification information are stored in the storage unit  31 . Note that, the specific phase list  30 D is extracted by the control unit  21  by using history information (game log) of each player U, in a manner similar to the extraction unit  20 A according to the first embodiment. 
     The extraction device  11  collects the first history information  30 A, the second history information  30 B, and the player history information  30 C from one or more game devices  14  or an external device via the network N and stores the collected information in the storage unit  31 . 
     Next, the control unit  21  will be described. The control unit  21  controls the extraction device  11 . The control unit  21  includes an extraction unit  21 A, a learning unit  21 B, an identification unit  21 C, and a communication control unit  21 E. 
     Part or all of the extraction unit  21 A, the learning unit  21 B, the identification unit  21 C, and the communication control unit  21 E may be achieved, for example, by causing a processing device such as a CPU to execute a program, that is, by using software, may be achieved by using hardware such as an IC, or may be achieved by using both of the software and the hardware. 
     The extraction unit  21 A extracts a specific phase τ of a game on the basis of the first history information  30 A of the first player U 1  and the second history information  30 B of the second player U 2 , in a manner similar to the extraction unit  20 A according to the first embodiment. 
     Here, in the present embodiment, the extraction unit  21 A extracts the specific phase τ for the other players U by using the player history information  30 C of the respective players U and the second history information  30 B, in a manner similar to the extraction of the specific phase τ for the first player U 1 . Then, in association with the identification information about each of the plurality of players U, the extraction unit  21 A stores the extracted specific phase list  30 D for each player U, in the storage unit  31 . For example, every time the player history information  30 C is updated, the extraction unit  21 A preferably extracts the specific phase τ for each player U and stores the specific phase τ in the storage unit  31 , in association with the identification information about the player U. 
     In the present embodiment, when extracting a new specific phase τ for a player U, the extraction unit  21 A uses the specific phase τ shown in the specific phase list  30 D stored in the storage unit  31 , as a training phase. 
     For example, it is assumed that a specific phase τ for the first player U 1  is extracted. 
     In this case, the extraction unit  21 A extracts a specific phase τ first on the basis of the first history information  30 A of the first player U 1  and the second history information  30 B of the second player U 2 , in a manner similar to the extraction unit  20 A according to the first embodiment. 
     Here, the specific phase τ extracted by the extraction unit  21 A on the basis of the first history information  30 A of the first player U 1  and the second history information  30 B of the second player U 2  does not include a phase that is not played by the first player U 1 . However, even if a game phase is not played by the first player U 1 , another player U may have already played the game phase. In addition, a specific phase τ not played by the first player U 1  may be extracted as a learning target for another player U with the same learning level as the first player U 1 . 
     Therefore, in the present embodiment, the extraction unit  21 A identifies a distribution of training phases similar to a specific phase τ extracted on the basis of the first history information  30 A of the first player U 1 , from a distribution of training phases (specific phases) shown in the specific phase list  30 D stored in the storage unit  31  corresponding to each of the plurality of players U. For identification of the distribution of similar training phases, a well-known collaborative filtering algorithm or the like is preferably used. 
     Next, the extraction unit  21 A identifies a training phase that is not included in a distribution of the specific phases τ for the first player U 1 , for the identified distribution of training phases. Then, the extraction unit  21 A further extracts the identified training phase as a specific phase τ for the first player U 1 . 
     Therefore, the extraction unit  21 A is capable of further extracting, as the specific phase τ for the first player U 1 , training phases of another player U having a distribution of specific phases τ similar to that for the first player U 1  and not extracted as the specific phase τ for the first player U 1 . 
     In other words, the specific phases τ extracted for the first player U 1  by the extraction unit  21 A in the present embodiment includes a specific phase τ extracted on the basis of the first history information  30 A of the first player U 1  and a specific phase τ extracted on the basis of a player history information  30 C of another player U. The specific phase τ extracted on the basis of the first history information  30 A of the first player U 1  is a phase that the first player U 1  needs to learn. Furthermore, the specific phase τ extracted on the basis of a player history information  30 C of another player U is a phase that the first player U 1  has not yet experienced but is a phase that is highly likely to need to learn. 
     Note that a label may be assigned to each of the specific phases τ extracted for the first player U 1  by the extraction unit  21 A, according to a method of extracting the particular phase τ. For example, a label “+1” may be assigned to a specific phase τ that needs to be learned, a label “+0.5” to a specific phase τ that is unexperienced but highly likely to need learning, and further the extraction unit  21 A may assign a label “0” indicating that the learning level is not determined due to no experience to the other phases not extracted for the first player U 1 . In addition, when a specific phase τ to which the label “+1” or the label “+0.5” is assigned includes the first command signal in the specific phase τ included in the latest first history information  30 A of the first player U 1  and the first command signal is a signal similar to the second command signal, the extraction unit  21 A determines that further learning is unnecessary, and a label “−1” may be assigned. 
     In this way, assignment of a label to each of the specific phases τ by the extraction unit  21 A facilitates selection of a specific phase τ as the learning target in the information processing device  12 . For example, the output control unit  32 C of the information processing device  12  preferably outputs the guiding command information to the game device  14  so as to preferentially learn a specific phase τ to which the label “+1” or “+0.5” is assigned, from among specific phases τ received from the extraction device  11 . 
     Next, the identification unit  21 C will be described. The identification unit  21 C, on the basis of a specific phase τ extracted by the extraction unit  21 A and a learning model, identifies a cluster to which the specific phase τ belongs and at least one of the label  48  and the priority  49  of the cluster. 
     The identification unit  21 C uses a learning model learned by the learning unit  21 B. 
     For example, the learning unit  21 B collects specific phase lists of specific phases τ, results of clustering the specific phases τ of the specific phase lists, and labels  48  and priority  49  assigned to the respective clusters, via the network N and stores the specific phase lists, results of clustering, and labels  48  and priority  49  in the storage unit  31 , the specific phase lists of specific phases τ being extracted for the respective players U by the extraction device  10  described in the first embodiment, the extraction device  11  in other embodiments, or the like. The learning unit  21 B uses, as training data, the specific phase lists of specific phases τ extracted for the respective players U, the clusters to which the specific phases τ belong, and the labels  48  and the priority  49  that are assigned to the clusters. 
     Then, the learning unit  21 B uses the training data to learn a learning model for deriving, from a specific phase τ, a cluster to which the specific phase τ belongs and at least one of a label  48  and priority  49  for the cluster. The learning unit  21 B is preferably learn the learning model by performing classification learning and regression learning using known machine learning such as long short-term memory (LSTM). 
     The identification unit  21 C introduces the specific phase τ extracted by the extraction unit  21 A into the learning model to identify a cluster to which the specific phase τ belongs and at least one of the label  48  and priority  49  of the cluster. Therefore, in the present embodiment, the extraction device  11  is capable of identifying a cluster to which the specific phase τ belongs and at least one of the label  48  and priority  49  of the cluster without through an operation command from the third player U 3  through the UI unit  23 . 
     The communication control unit  21 E transmits a specific phase list of specific phases τ extracted by the extraction unit  21 A to the information processing device  12  via the communication unit  26 . Note that the communication control unit  21 E may transmit, to the information processing device  12 , the specific phase list of specific phases τ, a result of clustering, and at least one of a label  48  and priority  49  that is assigned to a cluster. 
     [Procedure of Extraction Processing According to Fourth Embodiment] 
     Next, an example of a procedure of extraction processing performed by the extraction device  11  will be described. 
       FIG.  16    is a flowchart illustrating an example of the procedure of extraction processing performed by the extraction device  11 . 
     First, the extraction unit  21 A reads the first history information  30 A and the second history information  30 B from the storage unit  31  (Step S 500 ). 
     Next, the extraction unit  21 A extracts a specific phase τ on the basis of the first history information  30 A and the second history information  30 B read in Step  500  (Step S 502 ). 
     Next, the extraction unit  21 A identifies a distribution of training phases similar to the specific phase τ extracted in Step S 502 , from a distribution of training phases (specific phases) shown in the specific phase list  30 D stored in the storage unit  31  corresponding to each of the plurality of players U (Step S 504 ). 
     Next, the extraction unit  21 A identifies a training phase that is not included in a distribution of the specific phases τ extracted in Step S 502 , for the distribution of training phases identified in Step S 504  (Step S 506 ). 
     Next, the identification unit  21 C introduces the specific phase τ extracted in Step S 502  and the specific phases τ as the training phases identified in Step S 506  into the learning model and performs clustering of the specific phases τ and assignment of the label  48  and priority  49  to the cluster (Step S 508 ). 
     Next, the communication control unit  21 E transmits a specific phase list including the specific phase τ extracted in Step S 502  and the specific phase τ identified as the training phase in Step S 506  to the information processing device  12  via the communication unit  26  (Step S 510 ). Note that the communication control unit  21 E may transmit, to the information processing device  12 , the specific phase list of specific phases τ, a result of clustering in Step S 508 , and at least one of a label  48  and priority  49  that is assigned to a cluster. Then, this routine is finished. 
     As described above, the extraction unit  21 A of the extraction device  11  according to the present embodiment further extracts, as a specific phase τ for the first player U 1 , a training phase that is not included in a distribution of specific phases τ, for a distribution of training phases similar to the distribution of specific phases τ extracted from the distribution of training phases as specific phases τ corresponding to each of a plurality of players U on the basis of the first history information  30 A. 
     Therefore, the extraction unit  21 A is capable of further extracting, as the specific phase τ for the first player U 1 , training phases of another player U having a distribution of specific phases τ similar to that for the first player U 1  and not extracted as the specific phase τ for the first player U 1 . 
     Therefore, the extraction device  11  according to the present embodiment can further effectively support the improvement in learning level, in addition to the effects of the above-described embodiment. 
     Note that although the embodiments and modifications thereof according to the present disclosure have been described above, the processing according to the above embodiments and modifications may be performed in various different forms in addition to the above embodiments and modifications. Furthermore, the above embodiments and modifications can be appropriately combined within a range consistent with the contents of the processing. 
     Furthermore, the effects described herein are merely examples, the present invention is not limited to these effects, and other effects may also be provided. 
     [Targets to which Extraction Device and Information Processing Device According to Above Embodiments and Modifications are to be Applied] 
     Targets to which the extraction devices  10  and  11  and the information processing devices  12 ,  12 B, and  12 C according to the above embodiments and modifications are to be applied are not limited. For example, the extraction devices  10  and  11  and the information processing devices  12 ,  12 B, and  12 C can be applied to a system that uses the game device  14  or a development tool kit that is used for a game developer. 
     In a case where the extraction devices  10  and  11  and the information processing devices  12 ,  12 B, and  12 C are applied to the development tool kit for game developers, a training game for characters, avatars, or the like that function in the game or development of artificial intelligence (AI) mounted in a game are made efficient, in addition to the effects of the above embodiments and modifications. 
     (Hardware Configuration) 
       FIG.  17    is a hardware configuration diagram illustrating an example of a computer  1000  that achieves the functions of the extraction devices  10  and  11  and the information processing devices  12 ,  12 B, and  12 C according to the above-described embodiments and modifications. 
     The computer  1000  includes a CPU  1100 , a RAM  1200 , a read only memory (ROM)  1300 , a hard disk drive (HDD)  1400 , a communication interface  1500 , and an input/output interface  1600 . Each unit of the computer  1000  is connected by a bus  1050 . 
     The CPU  1100  is operated on the basis of a program stored in the ROM  1300  or the HDD  1400  and controls each unit. For example, the CPU  1100  deploys a program stored in the ROM  1300  or the HDD  1400  to the RAM  1200  and executes processing corresponding to various programs. 
     The ROM  1300  stores a boot program such as a basic input output system (BIOS) executed by the CPU  1100  when the computer  1000  is booted, a program depending on hardware of the computer  1000 , and the like. 
     The HDD  1400  is a computer-readable recording medium that non-transitorily records a program executed by the CPU  1100 , data used by the program, and the like. Specifically, the HDD  1400  is a recording medium that records a program according to the present disclosure as an example of program data  1450 . 
     The communication interface  1500  is an interface for connecting the computer  1000  to an external network  1550  (e.g., the Internet). For example, the CPU  1100  receives data from another device or transmits data generated by the CPU  1100  to another device via the communication interface  1500 . 
     The input/output interface  1600  is an interface that connects between an input/output device  1650  and the computer  1000 . For example, the CPU  1100  receives data from an input device such as a keyboard or mouse via the input/output interface  1600 . In addition, the CPU  1100  transmits data to an output device such as a display, speaker, or printer via the input/output interface  1600 . Furthermore, the input/output interface  1600  may function as a media interface for reading a program or the like recorded on a predetermined recording medium. The medium includes, for example, an optical recording medium such as a digital versatile disc (DVD) or a phase change rewritable disk (PD), a magneto-optical recording medium such as a magneto-optical disk (MO), a tape medium, a magnetic recording medium, a semiconductor memory, or the like. 
     For example, when the computer  1000  functions as the information processing device  12  according to the first embodiment, the CPU  1100  of the computer  1000  achieves the function of the acquisition unit  32 A or the like by executing an information processing program loaded on the RAM  1200 . Furthermore, the HDD  1400  stores the information processing program according to the present disclosure or data in the storage unit  36 . Note that the CPU  1100  executes the program data  1450  read from the HDD  1400 , but as another example, the CPU  1100  may acquire these programs from another device via the external network  1550 . 
     Moreover, the present technology can also have the following configuration. 
     (1) 
     An information processing device comprising 
     an output control unit that, when a game status approaches a specific phase, outputs guiding command information guiding to a reproduced game status where the specific phase is reproduced, to a game device. 
     (2) 
     The information processing device according to (1), wherein 
     the specific phase 
     is represented by a time-series set of game statuses. 
     (3) 
     The information processing device according to (1) or (2), wherein 
     the output control unit 
     outputs, to the game device, the guiding command information that stepwisely or continuously guides a game status toward the reproduced game status. 
     (4) 
     The information processing device according to any one of (1) to (3), wherein 
     the specific phase 
     is a phase as a learning target for a first player. 
     (5) 
     The information processing device according to (4), wherein 
     the specific phase, 
     in a time-series set of second game statuses of a second player with a higher learning level than the first player, is a phase ranging from a time point where a distance to a time-series set of first game statuses in the past of the first player is equal to or less than a first threshold to a time point where the distance exceeds a second threshold that is larger than the first threshold. 
     (6) 
     The information processing device according to (5), wherein 
     the reproduced game status, 
     in a time-series set of second game statuses of the second player, represents the second game status at a time point where a distance to a time-series set of first game statuses in the past of the first player is equal to or less than the first threshold. 
     (7) 
     The information processing device according to any one of (4) to (6), wherein 
     the output control unit 
     outputs, to the game device, the guiding command information including at least one of the correction command signal and game status changing command information, the correction command signal causing the game status to change in a direction approaching the reproduced game status is obtained by correcting a first command signal received from the first player, and the game status changing command information changes a game status in a direction approaching the reproduced game status. 
     (8) 
     The information processing device according to any one of (4) to (6), in which 
     the output control unit 
     outputs, on the basis of priority assigned to a cluster to which the specific phase belongs, the guiding command information, for the specific phase belonging to the cluster having a higher priority, in priority to another specific phase belonging to another cluster. 
     (9) 
     The information processing device according to any one of (4) to (6), wherein 
     the output control unit, 
     for a duration of the specific phase, outputs, to the game device, a third command signal received from a third player with a higher learning level than the first player, instead of a first command signal received from the first player. 
     (10) 
     The information processing device according to any one of (4) to (6), wherein 
     the output control unit, 
     when a game status of a third game device that receives a third command signal from a third player with a higher learning level than the first player approaches the specific phase, outputs the guiding command information to the third game device as the game device, and 
     outputs, to the first player as a computer, a time-series set of the third command signals received from the third player for a duration of the specific phase. 
     (11) 
     An extraction device comprising 
     an extraction unit that extracts a specific phase of a game based on first history information indicating a time-series set of first game statuses of a first player and second history information indicating a time-series set of second game statuses of a second player with a higher learning level than the first player. 
     (12) 
     The extraction device according to (11), wherein 
     the extraction unit 
     extracts, as the specific phase, a phase ranging from a time point where a distance to a time-series set of first game statuses of the first player is equal to or less than a first threshold to a time point where the distance exceeds a second threshold that is larger than the first threshold, in the time-series set of second game statuses. 
     (13) 
     The extraction device according to (11) or (12), further comprising: 
     a classification unit that classifies a plurality of the specific phases into at least one or more clusters according to a classification rule specified by a fourth player; and 
     an assignment unit that assigns at least one of a label and priority to each of the clusters, in response to a command from the fourth player. 
     (14) 
     The extraction device according to (11) or (12), further comprising: 
     an identification unit that identifies a cluster to which the specific phase belongs and at least one of a label and priority of the cluster, based on a learning model for deriving, from the specific phase, a cluster to which the specific phase belongs and at least one of a label and priority of the cluster and the specific phase extracted by the extraction unit. 
     (15) 
     The extraction device according to any one of (11) to (14), wherein 
     the extraction unit 
     further extracts, as the specific phase for the first player, a training phase that is not included in a distribution of the specific phases, for a distribution of the training phases similar to the distribution of the specific phases extracted from the distribution of the training phases as the specific phases corresponding to each of a plurality of players based on the first history information. 
     (16) 
     Information processing method comprising 
     outputting, when a game status approaches a specific phase, guiding command information guiding to a reproduced game status where the specific phase is reproduced, to a game device, 
     wherein the step is performed by a computer. 
     (17) 
     An extraction method comprising 
     extracting a specific phase of a game based on first history information indicating a time-series set of first game statuses of a first player and second history information indicating a time-series set of second game statuses of a second player with a higher learning level than the first player, 
     wherein the step is performed by a computer. 
     REFERENCE SIGNS LIST 
     
         
         
           
               10 ,  11  EXTRACTION DEVICE 
               12 ,  12 B,  12 C INFORMATION PROCESSING DEVICE 
               20 A,  21 A EXTRACTION UNIT 
               32 C,  33 C,  35 C OUTPUT CONTROL UNIT