Patent Publication Number: US-2022232398-A1

Title: Quality estimation apparatus, model construction method, estimation method and program

Description:
TECHNICAL FIELD 
     The present invention relates to a technique for estimating QoE (quality of experience), which is quality experienced by the users who use services via a wireless network. 
     BACKGROUND ART 
     Related techniques for estimating QoE include, for example, Patent Literature 1. Patent Literature 1 discloses a technique that improves QoE of communications by sharing quality information about each application used on a communications terminal between a common carrier and user in cooperation with each other. 
     Specifically, the technique disclosed in Patent Literature 1, estimates QoE using quality information on the communications area to which the communications terminal belongs, and improves QoE by changing a connection destination based on estimation results. 
     CITATION LIST 
     Patent Literature 
     
         
         Patent Literature 1: Japanese Patent Laid-Open No. 2017-11419 
       
    
     SUMMARY OF THE INVENTION 
     Technical Problem 
     By estimating QoE on an area by area basis, it is possible to implement supervision and control over a network and services in terms of user experience. In so doing, due to differences in characteristics of areas (hereinafter referred to as area attributes), it is assumed that even when service quality is the same, QoE may vary. For example, it is conceivable that due to differences in usage or urgency, QoE evaluation characteristics may be stricter in business districts than in residential districts. 
     As described above, the technique disclosed in Patent Literature 1 estimates QoE using the quality information on the communications area to which the communications terminal is connected and improves QoE by changing a connection destination based on estimation results. However, the technique disclosed in Patent Literature 1 does not take area attributes into consideration in estimating QoE, and thus can overestimate QoE, for example, in business districts, which may result in overlooking quality deterioration related to user influence. 
     The present invention has been made in view of the above point and has an object to provide a technique that enables estimating QoE by taking into consideration the area attributes of the area in which the user is using a service. 
     Means for Solving the Problem 
     According to a disclosed technique, there is provided a quality estimation apparatus comprising: an acquisition unit configured to acquire quality information including QoEs and quality index values collected on a user terminal in a wireless network environment; and a construction unit configured to classify the QoEs and quality index values according to area attributes, the QoEs and quality index values being acquired by the acquisition unit, and construct QoE estimation models according to the respective area attributes using the QoEs and quality index values for the respective area attributes. 
     Effects of the Invention 
     The disclosed technique, implements QoE estimation close to user experience quality by adopting an optimum model for an area under evaluation from QoE estimation models constructed for the respective area attributes. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a diagram showing an example of a coverage according to an embodiment of the present invention. 
         FIG. 2  is a diagram showing an overall configuration of a system according to the embodiment of the present invention. 
         FIG. 3  is a diagram showing functional configurations of a user terminal  100  and base station  200 . 
         FIG. 4  is a diagram showing functional configurations of a quality information collection device  310  and quality information management device  320 . 
         FIG. 5  is a diagram showing an exemplary hardware configuration of a device. 
         FIG. 6  is a diagram showing an exemplary questionnaire screen on the user terminal  100 . 
         FIGS. 7( a ) to 7( c )  are diagrams showing an example of mapping between areas and area attributes. 
         FIG. 8  is a diagram showing an example of information recorded in a quality information recording unit  120 . 
         FIGS. 9( a ) to 9( c )  are diagrams showing quality information with each area attribute. 
         FIG. 10  is a diagram showing an image of information collection. 
         FIG. 11  is a diagram for explaining QoE estimation in a target evaluation area. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     An embodiment of the present invention will be described below with reference to the drawings. The embodiment described below is only exemplary, and embodiments to which the present invention is applicable are not limited to the embodiment described below. 
     In the following description, for example, LTE is cited as a communications scheme, this is exemplary, and the present invention is also applicable to 3G and 5G. 
     Overview of Embodiment 
     First, a brief overview of the embodiment will be provided. According to the present embodiment, in a wireless network environment such as LTE, from various quality information collected beforehand on a user terminal, QoE estimation models based on respective area attributes are constructed in a quality estimation system. The various quality information includes, for example, QoE, quality index values (such as Web loading time), position information (which may be area attributes), communications schemes (such as LTE and WiFi (registered trademarks))), and the like. 
     During QoE estimation, the quality estimation system  300  performs QoE estimation close to the quality experienced by users who actually use the system, by applying a QoE estimation model corresponding to an area attribute of an area under evaluation, based on quality index values and position information collected separately. Consequently, for example, if reduced QoE is confirmed in a target area, the band can be reinforced by expanding facilities on a priority basis. 
     Note that the “area” in the following description means an area of a predetermined size, such as a three-dimensional mesh. However, the “area” may be either smaller or larger than the three-dimensional mesh. Also, the “position information” described below means, for example, latitude and longitude, but in determining an area attribute, an “area” corresponding to the latitude and longitude is used. Also, the “position information” may identify an “area.” 
     The area attributes available for use include not only classification results such as business district and residential district, but also prefecture and municipality. Also, if it is assumed that characteristics may vary between weekdays and Saturdays/Sundays/holidays even if the place is the same, the area attributes may be further classified into business district on weekdays and business district on Saturdays/Sundays/holidays. In terms of the communications scheme, the area attributes may be further classified, for example, into LTE and WiFi (registered trademarks). The embodiment of the present invention will be described in more detail below. 
     Overall Configuration of System 
     According to the present embodiment, as shown in  FIG. 1 , a quality information collection device  310  collects various quality information about various places from one or more user terminals  100  connected to a mobile network. Part (such as position information) of the quality information may be collected as base station information from a base station  200 . 
     Then, the quality information management device  320  constructs QoE estimation models corresponding to area attributes from the collected quality information and performs QoE estimation using the QoE estimation models. In the example shown in  FIG. 1 , information is shown to be collected from all over Japan, but this is an example, and is not restrictive. For example, information may be collected from abroad, from all over the world, or from some regions of Japan. 
       FIG. 2  is a diagram showing an overall configuration of the system. LTE providing area A and LTE providing area B are shown as an example in  FIG. 2 . As shown in  FIG. 2 , the quality estimation system  300  includes the quality information collection device  310  and quality information management device  320  described above. 
     The quality estimation system  300  may be provided on a core network of a mobile network or provided on a network (e.g., the Internet) external to the mobile network. Alternatively, a certain base station may have a function of the quality estimation system  300 , or a certain user terminal may have a function of the quality estimation system  300 . In either case, the user terminal  100  and quality estimation system  300  can communicate with each other via a communications network. 
     The quality information collection device  310  collects quality information (including QoE, quality index values, and position information) from user terminals  100  existing in LTE providing areas. Also, the quality information collection device  310  may collect position information from the base station  200 . Based on the collected information, the quality information management device  320  constructs QoE estimation models according to respective area attributes. 
     Exemplary Functional Configurations of Devices 
       FIG. 3  is a diagram showing exemplary functional configurations of the user terminal  100  and base station  200 . As shown in  FIG. 3 , the user terminal  100  includes a quality information measurement unit  110 , a quality information recording unit  120 , and a quality information transmission unit  130 . The base station  200  includes a position information measurement unit  210  and a position information transmission unit  220 . Note that these functional parts on the user terminal  100  and base station  200  are functional parts related to a technique of the present invention, and the user terminal  100  and base station  200  are each equipped with various non-illustrated existing functional parts. 
     According to the present embodiment, the quality information measurement unit  110 , quality information recording unit  120 , and quality information transmission unit  130  of the user terminal  100  are implemented by a dedicated application (referred to as the “dedicated application α”) run on the user terminal  100 . The dedicated application α is capable of Web browsing for measuring quality information. However, it is only exemplary that the quality information measurement unit  110 , quality information recording unit  120 , and quality information transmission unit  130  are implemented by the dedicated application α. 
       FIG. 4  is a diagram showing exemplary functional configurations of the quality information collection device  310  and quality information management device  320 . As shown in  FIG. 4 , the quality information collection device  310  includes a collection unit  311 , a quality information recording unit  312 , a transmission unit  313 , and a generation unit  314 . The quality information management device  320  includes a construction unit  321 , a QoE estimation model recording unit  322 , a determination unit  323 , and an estimation unit  324 . 
     The collection unit  311  may be referred to as an acquisition unit. The collection unit  311  acquires the QoE and quality information including the quality index values collected on the user terminal in the wireless network environment. 
     The construction unit  321  classifies the acquired QoEs and quality index values according to area attributes and constructs QoE estimation models according to the respective area attributes using the QoEs and quality index values for the respective area attributes. 
     The determination unit  323  acquires the quality index value from a target user terminal whose QoE is to be estimated and determines the area attribute of the area in which the target user terminal is located, based on mapping information between areas and area attributes. Using the QoE estimation model corresponding to the area attribute determined by the determination unit  323 , the estimation unit  324  estimates the QoE on the target user terminal based on the quality index value acquired from the target user terminal. 
     The generation unit  314  generates the mapping information between areas and area attributes based on position information that indicates the position in which the user terminal is located and time-series information about the quality index value. 
     Note that although in the example described in the present embodiment, the quality information collection device  310  and quality information management device  320  are separate from each other, the quality information collection device  310  and quality information management device  320  may be implemented as a unified device. The unified device may be referred to as a quality estimation apparatus or quality estimation system. Also, the quality information management device  320  may be referred to as a quality estimation hardware. 
     Exemplary Hardware Configuration 
     The devices according to the present embodiment (user terminal  100 , base station  200 , quality information collection device  310 , quality information management device  320 , quality estimation system, and quality estimation apparatus) can be implemented, for example, by causing a computer to execute programs describing processing details of the present embodiment. Note that the “computer” may be a virtual machine provided by a cloud service. When a virtual machine is used, “hardware” described herein is virtual hardware. 
     The apparatus can be implemented by executing programs corresponding to the processes run on the apparatus using hardware resources such as a built-in CPU or memory of the computer. The programs can be saved or distributed by being recorded on a computer-readable recording medium (such as a portable memory). Also, the programs can be provided via a network, for example by means of electronic mail or the Internet. 
       FIG. 5  is a diagram showing an exemplary hardware configuration of the computer according to the present embodiment. The computer of  FIG. 5  includes a drive device  1000 , an auxiliary storage device  1002 , a memory device  1003 , a CPU  1004 , an interface device  1005 , a display device  1006 , and an input device  1007 , which are interconnected via a bus B. 
     The programs that implement the processes on the computer are provided, for example, via a recording medium  1001  such as a CD-ROM or memory card. When the recording medium  1001  containing the programs is set in the drive device  1000 , the programs are installed in the auxiliary storage device  1002  from the recording medium  1001  via the drive device  1000 . However, the programs do not necessarily have to be installed from the recording medium  1001 , and may be downloaded from another computer via a network. The auxiliary storage device  1002  stores necessary files, data, and the like as well as the installed programs. 
     When a program start command is issued, the memory device  1003  stores the programs by reading the programs out of the auxiliary storage device  1002 . According to the programs stored in the memory device  1003 , the CPU  1004  implements functions related to the quality estimation apparatus. The interface device  1005  is used as an interface for connecting to the network. The display device  1006  displays a GUI (Graphical User Interface) and the like provided by the programs. The input device  1007  is made up of a keyboard, a mouse, and buttons, or a touch panel and the like, and is used to enter various operating commands. 
     Operation examples of the user terminal  100 , base station  200 , quality information collection device  310 , and quality information management device  320  configured as described above will be described in detail below. 
     According to the present embodiment, a QoE estimation model corresponding to each area attribute is constructed and QoE is estimated using the constructed QoE estimation model based on the quality index value collected from the user terminal. 
     (Construction of QoE Estimation Model Corresponding to Each Area Attribute) 
     First, construction of a QoE estimation model corresponding to each area attribute will be described. QoE estimation of a Web browsing service in an LTE or other wireless network environment will be described here as an example. However, the QoE estimation of a Web browsing service is only exemplary, and the present invention is applicable without limitation to the QoE estimation of a Web browsing service. 
     The dedicated application α capable of Web browsing for measuring quality information has been installed on the user terminal  100 . Using functions of the dedicated application α, various quality information (QoE, quality index (such as Web loading time), position information, communications schemes (such as LTE and WiFi (registered trademarks))), area attributes) is acquired when the user is using Web browsing. Methods for acquiring various information will be described below. 
     &lt;Measurement of QoE&gt; 
     First, QoE measurement on the user terminal  100  will be described with reference to  FIG. 6 . 
     It is assumed that the user uses, for example, a Web browsing service in an LTE or other wireless network environment. The user starts the dedicated application α on the user terminal  100  and gives an answer about QoE (user experience quality) at that time on a questionnaire screen displayed by a function (the quality information measurement unit  110  in the configuration diagram of  FIG. 3 ) of the dedicated application α ( FIG. 3 ). The dedicated application α is designed to allow the user himself/herself to answer questions provided in the form of a questionnaire, and is able to collect quality information in the background (quality index values and the like). 
     To describe with reference to the functional configurations of  FIG. 3 , the quality information measurement unit  110  displays the questionnaire screen and records the answer entered by the user in the quality information recording unit  120 . Also, the quality information measurement unit  110  automatically measures the quality index values (such as Web loading time) in the background and records measurement results in the quality information recording unit  120 . Besides, when recording the quality index values in the quality information recording unit  120 , the quality information measurement unit  110  also records the communications scheme (such as LTE or WiFi (registered trademarks) used at this time as well as the current time in the quality information recording unit  120 . 
     In the example of  FIG. 6 , an answer to a satisfaction rating of Web browsing is given by being triggered by the user, but a signal prompting an answer may be transmitted to the user terminal  100  from the quality information management device  320  (or quality information collection device  310 ) as required. Upon reception of the signal, for example, an answer screen starts up on the user terminal  100 . 
     &lt;Measurement of Quality Index Values&gt; 
     As described above, measurements of the quality index values (such as Web loading time) are taken automatically by the dedicated application α when a Web browsing service is being used in the LTE or other wireless network environment. 
     &lt;Acquisition of Area Attribute&gt; 
     Next, acquisition of an area attribute will be described. An area attribute is acquired, for example, as the user himself/herself gives an answer to a questionnaire. As shown, for example, in  FIG. 6 , the user enters the area attribute (shown as “measurement location” in  FIG. 6 ) on a screen displayed by the dedicated application α (the quality information measurement unit  110  of the user terminal  100 ). Information about the entered area attribute is recorded in the quality information recording unit  120 . 
     Also, the dedicated application α (the quality information measurement unit  110  of the user terminal  100 ) may acquire position information (e.g., latitude and longitude) using a GPS function, acquire an area attribute using mapping information between an area identified by the position information and the area attribute, and record the acquired area attribute in the quality information recording unit  120 . 
     The mapping information between areas and area attributes may be generated by the user terminal  100  as described later and held in the user terminal  100  beforehand or generated and held by a server on the Internet and then used by the user terminal  100  by accessing the server. The server may be the quality information collection device  310  or quality information management device  320 . 
     Also, the area attributes may be acquired by the quality information collection device  310  rather than the user terminal  100 . In that case, the user terminal  100  transmits position information (contained in quality information) to the quality information collection device  310 , which then converts the position information into an area attribute using the mapping information between areas and area attributes held in a storage device of the quality information collection device  310 . The quality information collection device  310  may generate the mapping information between areas and area attributes by itself using the generation unit  314  or acquire mapping information between areas and area attributes from another server or the like. Alternatively, the quality information management device  320  may generate mapping information between areas and area attributes. 
     Also, a position information measurement unit  210  of the base station  200  may measure position information about the user terminal  100  such that the position information transmission unit  220  will transmit the position information to the quality information collection device  310  in order for the quality information collection device  310  to convert the position information into an area attribute using the mapping information between areas and area attributes. In that case, however, the quality information collection device  310  links acquisition time of the quality information (QoE, quality index value, etc.) on the user terminal  100  to acquisition time of the position information about the user terminal  100  acquired on the base station  200 . That is, the quality information (QoE, quality index value, etc.) and position information (area attribute) acquired at the same acquisition time are used. 
     &lt;Mapping Generation Between Areas and Area Attributes&gt; 
     Now, description will be given of a method for generating mapping information between areas and area attributes, the method being performed by the user terminal  100  (or the quality information collection device  310 ). First, description will be given by citing a case in which the user terminal  100  generates mapping information. Note that the mapping information may be generated by the quality information measurement unit  110  of the user terminal  100  or a functional part of the user terminal  100  other than the quality information measurement unit  110 . 
     The quality information recording unit  120  of the user terminal  100  stores time-series information about the quality index value in relation to each area (position information) in which the user terminal  100  exists and uses a service. The user terminal  100  determines the area attribute of the area based, for example, on variability characteristics of the quality index value of the area. 
     A specific example will be described with reference to  FIG. 7 . The user terminal  100  reads quality index values (such as Web loading time) recorded for an area out of the quality information recording unit  120  and grasps peak generation characteristics (specifically, the number of times and generation time slots are grasped) of time-series quality index values. 
     For example, if peaks are generated twice, in the morning and evening (if the Web loading time is longer than at the same time on holidays) as shown in  FIG. 7( a ) , it is highly likely that the area is a commuting route (□ traffic line), and consequently the area attribute (area attribute A in  FIG. 7( a ) ) of the area is determined to be a “traffic line.” 
     Also, if a peak appears only in a time slot corresponding to a lunch break as shown in  FIG. 7( b ) , the area attribute (area attribute B in  FIG. 7( b ) ) of the area is determined to be a “business district.” Also, if a peak appears only in the nighttime as shown in  FIG. 7( c ) , the area attribute (area attribute C in  FIG. 7( c ) ) of the area is determined to be a “business district.” 
     Also, if it is assumed that evaluation characteristics vary between weekdays and holidays such as in business districts, the area attribute of data acquired on weekdays and the area attribute of data acquired on holidays may be classified into different area attributes, with the former being classified into “weekday business district” and the latter being classified into “holiday business district.” 
     Note that it is assumed that quality will vary with the communications scheme (LTE or WiFi (registered trademarks)) that is used, and thus even if the area is the same (such as business districts), the data acquired with these communications schemes may be similarly classified into different area attributes. For example, a business district that uses LTE may be designated as an “LTE business district.” 
     The user terminal  100  holds generated mapping information between areas and area attributes, for example, in the quality information recording unit  120 . 
     When the generation unit  314  of the quality information collection device  310  generates mapping information between areas and area attributes, processing details are the same as described above. However, the quality information collection device  310  generates the mapping information between areas and area attributes using quality information (the information stored in the quality information recording unit  312 ) collected from one or more user terminals  100 . 
     Note that the quality index values and position information data used here may be collected not only by the dedicated application α, but also by a dedicated application β described later. 
     &lt;Collection of Answers and Measurement Results&gt; 
     The user terminal  100  temporarily records the QoE, quality index values, communications schemes, position information, and the like acquired by the method described so far in the quality information recording unit  120 . An example of information recorded in the quality information recording unit  120  is shown in  FIG. 8 . In the example of  FIG. 8 , time (answer/measurement date and time), QoE, quality index value (Web loading time), communications scheme, and position information are recorded. When the area attribute is acquired on the side of the user terminal  100 , the area attribute corresponding to the position information may be recorded additionally. 
     The quality information transmission unit  130  of the user terminal  100  reads information (information yet to be transmitted) out of the quality information recording unit  120  and transmits the information to the quality information collection device  310 , for example, periodically. Also, the quality information transmission unit  130  of the user terminal  100  may read information (information yet to be transmitted) out of the quality information recording unit  120  upon receiving a request from the quality information management device  320 , which manages quality information, and transmit the information to the quality information collection device  310 . Also, the quality information transmission unit  130  of the user terminal  100  may read information (information yet to be transmitted) out of the quality information recording unit  120  when “Transmit” shown in  FIG. 6  is tapped, and transmit the information to the quality information collection device  310 . 
     The collection unit  311  of the quality information collection device  310  receives quality information transmitted from the user terminals  100  and records the quality information in the quality information recording unit  312 . Also, when no quality information is transmitted from any of the user terminals  100  or in similar situations, the generation unit  314  of the quality information collection device  310  finds the area attribute corresponding to the position information (or the time and communications scheme as well) contained in the quality information received from the user terminal  100  based on the mapping information between areas and area attributes, and records the area attribute in the quality information recording unit  312 . 
     As shown, for example, in  FIG. 9 , the collection unit  311  of the quality information collection device  310  records the quality information classified by area attribute and rearranged in time sequence in the quality information recording unit  312 . Note that the classification of information by area attribute such as shown in  FIG. 9  may be performed by the construction unit  321  of the quality information management device  320 . 
     The transmission unit  313  of the quality information collection device  310  reads (information yet to be transmitted) out of the quality information recording unit  312  and transmits the information to the quality information management device  320 , for example, periodically. Also, the transmission unit  313  of the quality information collection device  310  may read information (information yet to be transmitted) out of the quality information recording unit  312  upon receiving a request from the quality information management device  320 , which manages quality information, and transmit the information to the quality information collection device  310 . 
     &lt;Construction of QoE Estimation Model Corresponding to Each Area Attribute&gt; 
     The construction unit  321  of the quality information management device  320  receives quality information (QoE and quality index values (such as Web loading time) here) classified by area attribute from the quality information collection device  310  and constructs QoE estimation models according to the respective area attributes using the quality information. The QoE estimation models are used to estimate the QoE quality index values (such as Web loading time). 
     The method for constructing a QoE estimation model corresponding to each area attribute is not limited to a specific method. For example, the construction unit  321  inputs the QoE quality index value to the QoE estimation model in relation to each area attribute, adjusts parameters of the QoE estimation model so as to reduce a difference between an output QoE and correct QoE, and thereby constructs a QoE estimation model corresponding to each area attribute. 
     Also, for example, in the case of a Web browsing service, a QoE estimation model may be constructed based on a relationship between QoEs and quality index values using a technique described in Japanese Patent Laid-Open No. 2017-1 94756 (title of the invention: Web browsing quality estimation apparatus, Web browsing quality estimation method, and program). The unit of input data used in constructing the QoE estimation model may be day, week, month, or the like. If there are plural items of input data, a representative value (a mean value, maximum value, or the like) may be used. 
     The QoE estimation models (specifically, optimized parameters or the like) constructed according to respective area attributes are recorded in the QoE estimation model recording unit  322 . 
     (Estimation of QoE in Area Under Evaluation) 
     Next, QoE estimation on the user terminal  100  in the area under evaluation using the QoE estimation model will be described. 
     It is assumed here that the dedicated application β has been installed on the user terminal  100 . Using functions of the dedicated application β, the user terminal  100  running the dedicated application β periodically takes measurements in the background in the LTE or other wireless network environment and collects quality index values (such as Web loading time), position information (such as latitude and longitude), communications schemes (LTE and WiFi (registered trademarks)), and the like as measurement results. Note that the dedicated application β may be the dedicated application α or an application other than the dedicated application α. 
     The measurement results collected by the user terminal  100  is temporarily recorded in the user terminal  100 . The information recorded is, for example, the quality information shown in  FIG. 8  excluding QoE. The user terminal  100  transmits the measurement results to the quality information management device  320 , for example, periodically. Alternatively, the user terminal  100  may transmit the measurement results to the quality information management device  320  when there is a request from the quality information management device  320 . Besides, the measurement results transmitted by the user terminal  100  may be received by the quality information collection device  310 , and then transferred to the quality information management device  320  by the quality information collection device  310 . An image of how measurement results are collected is shown in  FIG. 10 . 
     Note that instead of the user terminal  100  collecting and transmitting its own position information, the base station  200  may collect and transmit the position information about the user terminal  100  to the quality information management device  320 . In that case, however, the quality information management device  320  needs to link measurement time of the position information and measurement time of the quality index value to each other. 
     The determination unit  323  of the quality information management device  320  holds the mapping information between the areas identified by the position information and the area attributes. An image of this is shown in  FIG. 11 . The mapping information between areas and area attributes may be generated by the quality information management device  320  itself, acquired by the quality information management device  320  from the quality information collection device  310  generating the mapping information, or acquired by the quality information management device  320  by another method. 
     Upon receiving measurement results (quality index value, position information, etc.) from the user terminal  100 , the determination unit  323  of the quality information management device determines the area attribute corresponding to (the area corresponding to) the position information from the mapping information and informs the determined area attribute to the estimation unit  324 . 
     The estimation unit  324  acquires the QoE estimation model corresponding to the area attribute from the QoE estimation model recording unit  322  and estimates the QoE on the user terminal  100  from the quality index value using the QoE estimation model. 
     In the example of  FIG. 11 , the QoE on the user terminal  100  existing in the area with area attribute C is estimated using QoE model C. 
     Effect of Embodiment 
     The technique according to the present embodiment can implement QoE estimation close to user experience by adopting an optimum model for an area under evaluation from QoE estimation models constructed for the respective area attributes beforehand. 
     Summary of Embodiment 
     As has been described above, the present specification discloses at least the following matters. 
     (Item 1) 
     A quality estimation apparatus comprising: 
     an acquisition unit configured to acquire quality information including QoEs and quality index values collected on a user terminal in a wireless network environment; and 
     a construction unit configured to classify the QoEs and quality index values according to area attributes, the QoEs and quality index values being acquired by the acquisition unit, and construct QoE estimation models according to the respective area attributes using the QoEs and quality index values for the respective area attributes. 
     (Item 2) 
     The quality estimation apparatus according to item 1, comprising: 
     a determination unit configured to acquire a quality index value from a target user terminal whose QoE is to be estimated and determine an area attribute of an area in which the target user terminal is located, based on mapping information between areas and area attributes; and 
     an estimation unit configured to estimate QoE on the target user terminal based on the quality index value acquired from the target user terminal, using the QoE estimation model corresponding to the area attribute determined by the determination unit. 
     (Item 3) 
     The quality estimation apparatus according to item 1 or 2, comprising a generation unit configured to generate mapping information between areas and area attributes based on position information that indicates a position in which the user terminal is located and time-series information about the quality index values. 
     (Item 4) 
     The quality estimation apparatus according to item 3, wherein the generation unit generates the mapping information based on the number of peaks in the quality index values and on time slots in which the peaks occur. 
     (Item 5) 
     A model construction method performed by a quality estimation apparatus, the method comprising: 
     an acquisition step of acquiring quality information including QoEs and quality index values collected on a user terminal in a wireless network environment; and 
     a construction step of classifying the QoEs and quality index values according to area attributes, the QoEs and quality index values being acquired by the acquisition step, and constructing QoE estimation models according to the respective area attributes using the QoEs and quality index values for the respective area attributes. 
     (Item 6) 
     An estimation method performed by a quality estimation apparatus, the method comprising: 
     an acquisition step of acquiring quality information including QoEs and quality index values collected on a user terminal in a wireless network environment; 
     a construction step of classifying the QoEs and quality index values according to area attributes, the QoEs and quality index values being acquired by the acquisition step, and constructing QoE estimation models according to the respective area attributes using the QoEs and quality index values for the respective area attributes; 
     a determination step of acquiring a quality index value from a target user terminal whose QoE is to be estimated and determining an area attribute of an area in which the target user terminal is located, based on mapping information between areas and area attributes; and 
     an estimation step of estimating QoE on the target user terminal based on the quality index value acquired from the target user terminal, using the QoE estimation model corresponding to the area attribute determined by the determination step. 
     (Item 7) 
     A program that causes a computer to function as the units of the quality estimation apparatus according to any one of items 1 to 4. 
     Whereas an embodiment of the present invention has been described above, the present invention is not limited to such a specific embodiment, and various modifications and changes can be made without departing from the spirit and scope of the invention set forth in the appended claims. 
     REFERENCE SIGNS LIST 
     
         
         
           
               100  User terminal 
               110  Quality information measurement unit 
               120  Quality information recording unit 
               130  Quality information transmission unit 
               200  Base station 
               210  Position information measurement unit 
               220  Position information transmission unit 
               310  Quality information collection device 
               311  Collection unit 
               312  Quality information recording unit 
               313  Transmission unit 
               314  Generation unit 
               320  Quality information management device 
               321  Construction unit 
               322  QoE estimation model recording unit 
               323  Determination unit 
               324  Estimation unit 
               1000  Drive device 
               1001  Recording medium 
               1002  Auxiliary storage device 
               1003  Memory device 
               1004  CPU 
               1005  Interface device 
               1006  Display device 
               1007  Input device