Patent Publication Number: US-2023162264-A1

Title: Shoe purchase recommendation device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority to and incorporates by reference the entire contents of Japanese Patent Application No. 2021-190747 filed in Japan on Nov. 25, 2021. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a shoe purchase recommendation device that predicts a change in a foot size of a prediction target person and recommends purchase of shoes. 
     2. Description of the Related Art 
     It is desired to wear shoes having an appropriate volume suited to the foot size of a wearer, such as a foot length, a foot circumference, and an arch height, and wearing shoes having an inappropriate volume may cause hallux valgus or may cause a shoe blister. In particular, when the wearer is a child, wearing shoes having an inappropriate volume sometimes adversely affect the growth of the foot. 
     Since the foot size changes with growth and aging, even a shoe having an optimum volume for the current foot size will not have an optimum volume for the foot size in the future in some cases. 
     WO 2021/130889 A discloses an invention that predicts a change in a foot length and notifies a customer of a replacement purchase of shoes. 
     WO 2021/130889 A discloses that a change in a foot length is predicted and a customer is notified of a replacement purchase of shoes, but does not disclose a specific method for notifying of a replacement purchase opportunity. Therefore, in the invention disclosed in WO 2021/130889 A, a user is not allowed to know a purchase-recommended date, which is an appropriate timing for purchasing shoes. 
     The present invention has been made in view of the above, and an object of the present invention is to obtain a shoe purchase recommendation device capable of notifying a user of a purchase-recommended date, which is an appropriate timing for purchasing shoes. 
     SUMMARY OF THE INVENTION 
     In order to solve the above-described problem and achieve the object, a shoe purchase recommendation device according to the present invention includes a user data storage unit that stores user data including at least an age and a foot size measurement value of a user, a foot size change prediction unit that calculates a change prediction value of a foot size of the user on a basis of the user data; a product information storage unit that stores product information including a shoe size; a purchase recommendation processing unit that determines a purchase-recommended date and a purchase-recommended product of shoes on a basis of the change prediction value and the product information; and a screen display processing unit that performs processing of displaying the purchase-recommended date, the purchase-recommended product, and a measurement-recommended date for the foot size. The screen display processing unit emphasizes and displays the purchase-recommended date and the purchase-recommended product when a number of days until the purchase-recommended date becomes equal to or less than a predetermined number of days. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a diagram illustrating a configuration of a shoe purchase recommendation device according to a first embodiment of the present invention; 
         FIG.  2    is a diagram illustrating an example of a normal notification screen displayed by a screen display processing unit of the shoe purchase recommendation device according to the first embodiment; and 
         FIG.  3    is a diagram illustrating an example of an emphasis notification screen displayed by the screen display processing unit of the shoe purchase recommendation device according to the first embodiment. 
         FIG.  4    is a flowchart illustrating a flow of action of the shoe purchase recommendation device according to the first embodiment; 
         FIG.  5    is a diagram illustrating a configuration of a shoe purchase recommendation device according to a second embodiment of the present invention; 
         FIG.  6    is a flowchart illustrating a flow of processing of the shoe purchase recommendation device according to the second embodiment to determine a purchase-recommended product; 
         FIG.  7    is a diagram illustrating a configuration of a shoe purchase recommendation device according to a third embodiment of the present invention; 
         FIG.  8    is a flowchart illustrating a flow of processing of the shoe purchase recommendation device according to the third embodiment to determine a purchase-recommended product; 
         FIG.  9    is a diagram illustrating a configuration of a shoe purchase recommendation device according to a fourth embodiment of the present invention; 
         FIG.  10    is a flowchart illustrating a flow of processing of the shoe purchase recommendation device according to the fourth embodiment to determine a purchase-recommended product; 
         FIG.  11    is a diagram illustrating a configuration of a shoe purchase recommendation device according to a fifth embodiment of the present invention; 
         FIG.  12    is a flowchart illustrating a flow of processing of the shoe purchase recommendation device according to the fifth embodiment to determine a purchase-recommended product; 
         FIG.  13    is a diagram illustrating a configuration of a shoe purchase recommendation device according to a sixth embodiment of the present invention; 
         FIG.  14    is a diagram illustrating a configuration of a shoe purchase recommendation device according to a seventh embodiment of the present invention; and 
         FIG.  15    is a diagram illustrating a hardware configuration example of the shoe purchase recommendation devices according to the first to seventh embodiments. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Hereinafter, embodiments of a shoe purchase recommendation device according to the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited by these embodiments. In addition, in the embodiments to be described below, the same or common parts are denoted by the same reference signs, and the description thereof will not be repeated. 
     In the following description, a case where the foot size is the foot length will be taken as an example. However, the foot size only has to be dimensions of a measurable portion, such as a foot circumference and an arch height, and is not limited to dimensions of a specific portion. In addition, the foot size may be a combination of dimensions of different portions of the foot, such as the foot length, the foot circumference, and the arch height, or may be three-dimensional scan data of the user&#39;s foot. Furthermore, not only the whole size of the foot but also the dimensions of a part of the shoe corresponding to the foot length, the foot circumference, the arch height, or the like may be regarded as the foot size. 
     First Embodiment 
       FIG.  1    is a diagram illustrating a configuration of a shoe purchase recommendation device according to a first embodiment of the present invention. A shoe purchase recommendation device  10 A includes: a user data storage unit  11  that stores user data  111  including at least an age  111 A, a foot size measurement value  111 B, and a foot size measurement date  111 C of a user; a foot size change prediction unit  12  that calculates a change prediction value of a foot size of the user on the basis of the user data  111 ; a product information storage unit  13  that stores product information  131  including a shoe size  131 A and a product image  131 B; a purchase recommendation processing unit  14  that determines a purchase-recommended date and a purchase-recommended product of shoes on the basis of the change prediction value and the product information  131 ; and a screen display processing unit  15  that performs processing of displaying a normal notification screen, to be described later, containing the purchase-recommended date, the purchase-recommended product, and a measurement-recommended date for the foot size, and an emphasis notification screen, to be described later, that emphasizes and displays the purchase-recommended date and the purchase-recommended product. The foot size measurement value  111 B is a measurement value of the foot size of the user measured in the past. The foot size measurement date  111 C is a date on which the foot size was measured in the past. The age  111 A is data representing elapsed time from birth. The age  111 A may be in “month old” representing the elapsed time from birth in units of months, instead of units of years. 
     The foot size change prediction unit  12  holds a foot size change table  121 , which is statistical data of changes in the foot size, and calculates a change prediction value of the foot size by adding an average change amount of the foot size based on the age  111 A to the foot size measurement value  111 B. The foot size change prediction unit  12  can calculate not only the prediction value of the foot size at a future time point dependent on the current foot size measurement value  111 B as a basis, but also the prediction value of the foot size at a past time point dependent on the past foot size measurement value  111 B as a basis. Note that the foot size change prediction unit  12  may calculate the change prediction value of the foot size by adding the change amount of the foot size based on data of the foot size of an older family member of the user included in the user data  111  stored in the user data storage unit  11 , to the foot size measurement value  111 B. 
     In addition to the age  111 A, the foot size measurement value  111 B, and the foot size measurement date  111 C, the user data  111  may include the height, weight, gender, residential region, current foot size data of the family member, and past foot size data of the family member. The foot size change prediction unit  12  calculates the change prediction value of the foot size using these pieces of information, whereby the change prediction value can be calculated by more accurately predicting the change in the foot size. In the shoe purchase recommendation device  10 A according to the first embodiment, the user data  111  includes a height  111 G and a weight  111 H of the user. Therefore, by calculating the change prediction value of the foot size using the age  111 A, the height  111 G, and the weight  111 H of the user and the foot size measurement value  111 B at the time point of the input age, the foot size change prediction unit  12  can calculate the foot size prediction value in consideration of the physique of the user. 
     A display input device  20  including a display unit  21  and an input unit  22  is connected to the shoe purchase recommendation device  10 A. A liquid crystal display or an organic electroluminescence display can be applied as the display unit  21 , but a display device other than these displays may be adopted. Input devices such as a keyboard and a pointing device can be applied as the input unit  22 , but an input device other than these input devices may be adopted. Note that a touch screen monitor having both of a display function and an input function together can also be applied as the display unit  21  and the input unit  22 . The display input device  20  is connected to the shoe purchase recommendation device  10 A via the Internet. Note that the display input device  20  may be directly connected to the shoe purchase recommendation device  10 A not via the Internet. In addition, the shoe purchase recommendation device  10 A may include the display unit  21  and the input unit  22 . In this case, the display input device  20  does not have to be connected to the shoe purchase recommendation device  10 A. 
     A foot size measuring device  30  is connected to the shoe purchase recommendation device  10 A. The foot size measuring device  30  outputs the foot size measurement value  111 B and the foot size measurement date  111 C obtained by measuring the foot size of the user. The foot size measurement value  111 B and the foot size measurement date  111 C are accumulated in the user data storage unit  11 . Note that the shoe purchase recommendation device  10 A may be provided with a user interface for input such that the foot size measurement value  111 B and the foot size measurement date  111 C are input by operating the user interface. In addition, the shoe purchase recommendation device  10 A may acquire the foot size measurement value  111 B and the foot size measurement date  111 C by communicating with another device that stores the foot size measurement value  111 B and the foot size measurement date  111 C. Furthermore, the foot size measurement date  111 C does not have to be data separated from the foot size measurement value  111 B and may be data of creation date and time or update date and time included in the file property of the foot size measurement value  111 B. 
     To give an example, a server of a shoe manufacturer can be applied as the shoe purchase recommendation device  10 A. In addition, a smartphone terminal of the user can be applied as the display input device  20 . Furthermore, a three-dimensional foot last automatic measuring instrument or an information terminal such as a smartphone terminal and a tablet terminal of the user can be applied as the foot size measuring device  30 . 
     The shoes are set with a foot size fitting range for each size. To give an example, for a certain shoe having a size of 20 cm, a foot length of 19.15 cm to 19.56 cm is set as the foot size fitting range. Accordingly, the day on which the foot length of the user reaches 19.15 cm is the purchase-recommended date on which the purchase of the shoes having a size of 20 cm is recommended. In this manner, the purchase recommendation processing unit  14  determines the day on which the change prediction value of the foot size of the user reaches the foot size fitting range of shoes that are the purchase target recommended product, as the purchase-recommended date. 
     The screen display processing unit  15  sets the day on which a preset period elapses from the previous foot size measurement date  111 C, as the measurement-recommended date. 
       FIG.  2    is a diagram illustrating an example of the normal notification screen displayed by the screen display processing unit of the shoe purchase recommendation device according to the first embodiment. A normal notification screen  200  contains a measurement-recommended date display area  201  in which the measurement-recommended date is displayed, a purchase recommendation display area  202  in which the purchase-recommended date and the purchase-recommended product are displayed, a message display area  203  in which a message for the user is displayed, and a previous measurement information display area  204  in which the most recent foot size measurement date  111 C and foot size measurement value  111 B are displayed. 
       FIG.  3    is a diagram illustrating an example of the emphasis notification screen displayed by the screen display processing unit of the shoe purchase recommendation device according to the first embodiment. When the number of days until the purchase-recommended date becomes equal to or less than a predetermined number of days, the screen display processing unit  15  performs processing of changing the normal notification screen  200  to an emphasis notification screen  300  in which the purchase recommendation display area  202  is emphasized. 
     Specifically, the purchase recommendation display area  202  is enlarged after the measurement-recommended date display area  201 , the message display area  203 , and the previous measurement information display area  204  are displayed in a reduced manner or hidden. The enlarged purchase recommendation display area  202  occupies a larger proportion in the screen and contains a purchase-recommended product image  202 A that has not been displayed on the normal notification screen  200 . The purchase-recommended product image  202 A is an image of a product to be purchased, and when the purchase recommendation processing unit  14  has determined a plurality of purchase-recommended products, the image of the purchase-recommended product having the highest recommendation priority is displayed at the center, while the image of the purchase recommendation target product having a recommendation priority other than the highest priority is displayed such that only a part of the image is accommodated within the purchase recommendation display area  202 . For example, the purchase-recommended product image  202 A for the purchase-recommended product having a recommendation priority other than the highest priority is displayed such that only the toe or only the heel is accommodated within the purchase recommendation display area  202 . In the purchase recommendation display area  202 , once the number of days until the purchase-recommended date becomes equal to or less than a predetermined number of days, the area of display is gradually enlarged as the number of days until the purchase-recommended date decreases. 
     When there is a plurality of purchase-recommended products, switch buttons  301  are displayed on the emphasis notification screen  300 . When the switch button  301  is pressed by operating the input unit  22 , the screen display processing unit  15  switches the purchase-recommended product image  202 A displayed at the center of the purchase recommendation display area  202 . Accordingly, by pressing the switch button  301  by operating the input unit  22 , the user of the display input device  20  can cause the display input device  20  to display the entire image of the purchase-recommended product having a recommendation priority other than the highest priority at the center of the purchase recommendation display area  202 . Note that, if the number of purchase-recommended products is too large, it is difficult for the user to decide which shoes to purchase, and thus the number of purchase-recommended products is preferably five or less. For example, in the shoe purchase recommendation device  10 A according to the first embodiment, by taking three as the number of purchase-recommended products, at least a part of the purchase-recommended product image  202 A of each purchase-recommended product is displayed in the purchase recommendation display area  202 , such that it becomes easy for the user to decide which shoes to purchase. 
     In addition, an emphasis display cancel button  302  is displayed in the purchase recommendation display area  202  of the emphasis notification screen  300 . When the emphasis display cancel button  302  is pressed by operating the input unit  22 , the screen display processing unit  15  performs processing of returning the normal notification screen  200  from the emphasis notification screen  300 . 
     Furthermore, a link  303  is displayed in the purchase recommendation display area  202  of the emphasis notification screen  300 . By pressing the link  303  by operating the input unit  22 , the user of the display input device  20  can purchase the shoes of which the purchase-recommended product image  202 A is displayed at the center of the purchase recommendation display area  202 , on an electronic commerce site. 
     To change the normal notification screen  200  to the emphasis notification screen  300 , the purchase recommendation display area  202  may be superimposed on the measurement-recommended date display area  201 , the message display area  203 , and the previous measurement information display area  204  by sliding the purchase recommendation display area  202 , or the purchase recommendation display area  202  may be transformed into a modal window and displayed by being superimposed on the measurement-recommended date display area  201 , the message display area  203 , and the previous measurement information display area  204 . In addition, the change from the normal notification screen  200  to the emphasis notification screen  300  may be performed by a method other than the method exemplified here. 
       FIG.  4    is a flowchart illustrating a flow of action of the shoe purchase recommendation device according to the first embodiment. In step S 11 , the foot size change prediction unit  12  calculates the change prediction value of the foot size of the user on the basis of the user data  111  stored in the user data storage unit  11 . In step S 12 , the purchase recommendation processing unit  14  determines the purchase-recommended date and the purchase-recommended product of shoes on the basis of the change prediction value calculated by the foot size change prediction unit  12  and the product information  131  stored in the product information storage unit  13 . 
     In step S 13 , the screen display processing unit  15  performs processing of displaying the normal notification screen  200 . In step S 14 , the screen display processing unit  15  verifies whether or not the number of days until the purchase-recommended date is equal to or less than a predetermined number of days. When the number of days until the purchase-recommended date is not equal to or less than the predetermined number of days, No is taken in step S 14 , and the process ends. When the number of days until the purchase-recommended date is equal to or less than the predetermined number of days, Yes is taken in step S 14 , and the process proceeds to step S 15 . 
     In step S 15 , the screen display processing unit  15  performs processing of changing the normal notification screen  200  to the emphasis notification screen  300 . 
     The shoe purchase recommendation device  10 A according to the first embodiment determines the purchase-recommended date and the purchase-recommended product on the basis of the change prediction value of the foot size of the user and the product information  131  including the shoe size  131 A and displays the determined purchase-recommended date and purchase-recommended product on the normal notification screen  200 . Accordingly, the shoe purchase recommendation device  10 A according to the first embodiment is capable of notifying the user of the purchase-recommended date, which is an appropriate timing for purchasing shoes. 
     Moreover, when the number of days until the purchase-recommended date becomes equal to or less than a predetermined number of days, the shoe purchase recommendation device  10 A according to the first embodiment performs processing of changing the normal notification screen  200  to the emphasis notification screen  300  in which the purchase recommendation display area  202  is displayed in an enlarged manner and thus can prompt the user not to miss the purchase-recommended date due to still overlooking the purchase-recommended date displayed in the purchase recommendation display area  202 . 
     Second Embodiment 
       FIG.  5    is a diagram illustrating a configuration of a shoe purchase recommendation device according to a second embodiment of the present invention. A shoe purchase recommendation device  10 B according to the second embodiment is different from the shoe purchase recommendation device  10 A according to the first embodiment in that a designated genre  111 D, which is a sports genre designated by a user, is included in user data  111 , and an application genre  131 C, which is a sports genre in which the shoes are used, is included in product information  131 . 
     When there are shoes of which the application genre  131 C matches the designated genre  111 D among candidates for the purchase-recommended product selected on the basis of the change prediction value of the foot size, a purchase recommendation processing unit  14  determines the purchase-recommended product by prioritizing the shoes of which the application genre  131 C matches the designated genre  111 D. 
       FIG.  6    is a flowchart illustrating a flow of processing of the shoe purchase recommendation device according to the second embodiment to determine the purchase-recommended product. In step S 21 , the purchase recommendation processing unit  14  selects candidates for the shoes recommended to purchase on the basis of the change prediction value of the foot size. In step S 22 , the purchase recommendation processing unit  14  verifies whether or not there are shoes of which the application genre  131 C matches the designated genre  111 D among the selected candidates. When there are shoes of which the application genre  131 C matches the designated genre  111 D, Yes is taken in step S 22 , and the processing proceeds to step S 23 . When there are no shoes of which the application genre  131 C matches the designated genre  111 D, No is taken in step S 22 , and the processing proceeds to step S 24 . 
     In step S 23 , the purchase recommendation processing unit  14  determines the purchase-recommended product from among the candidates selected in step S 21 , by prioritizing the shoes of which the application genre  131 C matches the designated genre  111 D. 
     In step S 24 , the purchase recommendation processing unit  14  determines the purchase-recommended product from among the candidates selected in step S 21 , by prioritizing shoes having a high degree of fitting in the foot size. Note that it is assumed that the shoes of which a median value of the foot size fitting range is closer to the foot size prediction value has a higher degree of fitting in the foot size. 
     The shoe purchase recommendation device  10 B according to the second embodiment can determine the purchase-recommended product by prioritizing shoes suitable for the genre designated in advance by the user, from among the shoes fitting to the change prediction value of the foot size of the user, and thus can recommend the purchase of the shoes suited to the preference of the user. 
     Note that approximate genres may be set in advance for sports genres that can be designated as the designated genre  111 D such that, when there are no shoes of which the application genre  131 C matches the designated genre  111 D, a product to be purchased is determined by prioritizing the shoes for the approximate genre. For example, competition groups such as an indoor court category including basketball, volleyball, and badminton, an outdoor limited contact category including soccer, rugby, and baseball, and an outdoor non-contact category including tennis, lacrosse, and track and field events may be set such that, when there are no shoes of which the application genre  131 C matches the designated genre  111 D among the candidates for the purchase-recommended product, the purchase recommendation processing unit  14  determines the purchase-recommended product by prioritizing the shoes for a competition belonging to the competition group including the designated genre  111 D. Note that the case where “there are no shoes of which the application genre matches the designated genre” includes both of a case where the commodity itself does not exist and a case where the commodity exists but there is no stock. 
     Third Embodiment 
       FIG.  7    is a diagram illustrating a configuration of a shoe purchase recommendation device according to a third embodiment of the present invention. A shoe purchase recommendation device  10 C according to the third embodiment is different from the shoe purchase recommendation device  10 A according to the first embodiment in that a designated color  111 E, which is a color designated by a user, is included in user data  111 , and a shoe color  131 D, which is information on the color of the shoes, is included in product information  131 . The shoe color  131 D is not limited to the color of a region occupying a large proportion on the outer surface of the shoe and may be a color of a logo mark provided on the outer surface of the shoe, or may be a color of a conspicuous part although occupying a small proportion on the outer surface of the shoe. 
     When there are shoes of which the shoe color  131 D matches the designated color  111 E among the candidates for the purchase-recommended product selected on the basis of the change prediction value of the foot size, a purchase recommendation processing unit  14  determines the purchase-recommended product by prioritizing the shoes of which the shoe color  131 D matches the designated color  111 E. 
       FIG.  8    is a flowchart illustrating a flow of processing of the shoe purchase recommendation device according to the third embodiment to determine the purchase-recommended product. In step S 31 , the purchase recommendation processing unit  14  selects candidates for the shoes recommended to purchase on the basis of the change prediction value of the foot size. In step S 32 , the purchase recommendation processing unit  14  verifies whether or not there are shoes of which the shoe color  131 D matches the designated color  111 E among the selected candidates. When there are shoes of which the shoe color  131 D matches the designated color  111 E, Yes is taken in step S 32 , and the processing proceeds to step S 33 . When there are no shoes of which the shoe color  131 D matches the designated color  111 E, No is taken in step S 32 , and the processing proceeds to step S 34 . 
     In step S 33 , the purchase recommendation processing unit  14  determines the purchase-recommended product from among the candidates selected in step S 31 , by prioritizing the shoes of which the shoe color  131 D matches the designated color  111 E. 
     In step S 34 , the purchase recommendation processing unit  14  determines the purchase-recommended product from among the candidates selected in step S 31 , by prioritizing shoes having a high degree of fitting in the foot size. Note that it is assumed that the shoes of which a median value of the foot size fitting range is closer to the foot size prediction value has a higher degree of fitting in the foot size. 
     The shoe purchase recommendation device  10 C according to the third embodiment can determine the purchase-recommended product by prioritizing the shoes of the color designated in advance by the user, from among the shoes fitting to the change prediction value of the foot size of the user, and thus can recommend the purchase of the shoes suited to the preference of the user. 
     Note that approximate colors may be set in advance for colors that can be designated as the designated color  111 E such that, when there are no shoes of which the shoe color  131 D matches the designated color  111 E, a product to be purchased is determined by prioritizing the shoes of the approximate color. For example, color groups such as a monotone category including black, white, and gray, a warm color category including red, pink, and brown, a cool color category including blue, purple, and green, and a light color category including orange, yellow, and gold may be set in advance such that, when there are no shoes of which the shoe color  131 D matches the designated color  111 E among the candidates for the purchase-recommended product, the purchase recommendation processing unit  14  determines the purchase-recommended product by prioritizing the shoes of a color belonging to the color group including the designated color  111 E. Note that the case where “there are no shoes of which the shoe color matches the designated color” includes both of a case where the commodity itself does not exist and a case where the commodity exists but there is no stock. 
     Fourth Embodiment 
       FIG.  9    is a diagram illustrating a configuration of a shoe purchase recommendation device according to a fourth embodiment of the present invention. A shoe purchase recommendation device  10 D according to the fourth embodiment is different from the shoe purchase recommendation device  10 A according to the first embodiment in that a designated genre  111 D, which is a sports genre designated by a user, and a designated color  111 E, which is a color designated by the user, are included in user data  111 , and an application genre  131 C, which is a sports genre in which the shoes are used, and a shoe color  131 D, which is information on the color of the shoes, are included in product information  131 . 
     A purchase recommendation processing unit  14  selects a purchase-recommended candidate collection of which the application genre  131 C matches the designated genre  111 D from among candidates for the purchase-recommended product selected on the basis of the change prediction value of the foot size, and determines the purchase-recommended product by prioritizing the shoes of which the shoe color  131 D matches the designated color  111 E from the purchase-recommended candidate collection. 
       FIG.  10    is a flowchart illustrating a flow of processing of the shoe purchase recommendation device according to the fourth embodiment to determine the purchase-recommended product. In step S 41 , the purchase recommendation processing unit  14  selects candidates for the shoes recommended to purchase on the basis of the change prediction value of the foot size. In step S 42 , the purchase recommendation processing unit  14  verifies whether or not there are shoes of which the application genre  131 C matches the designated genre  111 D among the selected candidates. When there are shoes of which the application genre  131 C matches the designated genre  111 D, Yes is taken in step S 42 , and the processing proceeds to step S 43 . When there are no shoes of which the application genre  131 C matches the designated genre  111 D, No is taken in step S 42 , and the processing proceeds to step S 44 . 
     In step S 43 , the purchase recommendation processing unit  14  selects the purchase-recommended candidate collection from among the shoes of which the application genre  131 C matches the designated genre  111 D among the candidates selected in step S 41 . 
     In step S 44 , the purchase recommendation processing unit  14  determines the purchase-recommended product from among the candidates selected in step S 41 , by prioritizing shoes having a high degree of fitting in the foot size. Note that it is assumed that the shoes of which a median value of the foot size fitting range is closer to the foot size prediction value has a higher degree of fitting in the foot size. After step S 44 , the processing ends. 
     In step S 45 , the purchase recommendation processing unit  14  verifies whether or not there are shoes of which the shoe color  131 D matches the designated color  111 E in the purchase-recommended candidate collection. When there are shoes of which the shoe color  131 D matches the designated color  111 E, Yes is taken in step S 45 , and the processing proceeds to step S 46 . When there are no shoes of which the shoe color  131 D matches the designated color  111 E, No is taken in step S 45 , and the processing proceeds to step S 47 . 
     In step S 46 , the purchase recommendation processing unit  14  determines the purchase-recommended product from among the shoes of which the shoe color  131 D matches the designated color  111 E in the purchase-recommended candidate collection selected in step S 43 . 
     In step S 47 , the purchase recommendation processing unit  14  randomly determines the purchase-recommended product from the purchase-recommended producct collection selected at Step  43 . 
     The shoe purchase recommendation device  10 D according to the fourth embodiment determines the shoes of which the shoe color  131 D matches the designated color  111 E from the purchase-recommended candidate collection, of which the application genre  131 C matches the designated genre  111 D, as the purchase-recommended product, and thus can recommend the purchase of the shoes that meet the conditions designated by the user. 
     Fifth Embodiment 
       FIG.  11    is a diagram illustrating a configuration of a shoe purchase recommendation device according to a fifth embodiment of the present invention. A shoe purchase recommendation device  10 E according to the fifth embodiment is different from the shoe purchase recommendation device  10 A according to the first embodiment in that a sporting ability measurement value  111 F, which is a measurement result for the sporting ability of a user, is included in user data  111 , and a desired sporting ability value  131 E, which is information on the sporting ability coupled with the shoes, is included in product information  131 . 
     Examples of the sporting ability include, but are not limited to, the time of short-distance running, the time of long-distance running, the height of vertical jump, and the number of times of repeated side stepping. The desired sporting ability value  131 E indicates the sporting ability desired to draw out the original potential of the shoes, and when the sporting ability measurement value  111 F of the wearer of the shoes is equal to or less than the desired sporting ability value  131 E, the original potential of the shoes will not be allowed to be drawn out. 
     When there are shoes of which the desired sporting ability value  131 E is equal to or less than the sporting ability measurement value  111 F among the candidates for the purchase-recommended product selected on the basis of the change prediction value of the foot size, a purchase recommendation processing unit  14  determines the purchase-recommended product by prioritizing the shoes of which the desired sporting ability value  131 E is equal to or less than the sporting ability measurement value  111 F. 
       FIG.  12    is a flowchart illustrating a flow of processing of the shoe purchase recommendation device according to the fifth embodiment to determine the purchase-recommended product. In step S 51 , the purchase recommendation processing unit  14  selects candidates for the shoes recommended to purchase on the basis of the change prediction value of the foot size. In step S 52 , the purchase recommendation processing unit  14  verifies whether or not there are shoes of which the desired sporting ability value  131 E is equal to or less than the sporting ability measurement value  111 F among the selected candidates. When there are shoes of which the desired sporting ability value  131 E is equal to or less than the sporting ability measurement value  111 F, Yes is taken in step S 52 , and the processing proceeds to step S 53 . When there are no shoes of which the desired sporting ability value  131 E is equal to or less than the sporting ability measurement value  111 F, No is taken in step S 52 , and the processing proceeds to step S 54 . 
     In step S 53 , the purchase recommendation processing unit  14  determines the purchase-recommended product from among the candidates selected in step S 51 , by prioritizing the shoes of which the desired sporting ability value  131 E is equal to or less than the sporting ability measurement value  111 F. 
     In step S 54 , the purchase recommendation processing unit  14  determines the purchase-recommended product from among the candidates selected in step S 51 , by prioritizing shoes having a high degree of fitting in the foot size. Note that it is assumed that the shoes of which a median value of the foot size fitting range is closer to the foot size prediction value has a higher degree of fitting in the foot size. 
     In particular, in sports shoes, a plurality of models is sometimes provided by performance of the wearer. In general, a model for beginners has specifications that give more importance on ease of handling than potential, whereas a model for advanced-level persons has specifications that give more importance on potential than ease of handling. Accordingly, if a person with low sporting ability wears a model for advanced-level persons, the original potential of the shoes will not be allowed to be sufficiently drawn out, and as a result, the wearer will not be able to sufficiently exhibit the own performance of the wearer. In addition, if a person with high sporting ability wears a model for beginners, the wearer will not be able to sufficiently exhibit the own performance of the wearer because the wearer is restricted by the potential of the shoes. By determining shoes recommended to purchase on the basis of the sporting ability of the user, the shoe purchase recommendation device  10 E according to the fifth embodiment can recommend the purchase of the shoes that allow the user to easily exhibit performance. 
     Sixth Embodiment 
       FIG.  13    is a diagram illustrating a configuration of a shoe purchase recommendation device according to a sixth embodiment of the present invention. A shoe purchase recommendation device  10 F according to the sixth embodiment is different from the shoe purchase recommendation device  10 A according to the first embodiment in including a purchase recommendation interval determination unit  16  that determines a purchase recommendation interval on the basis of an age  111 A of the user. 
     When the purchase-recommended date based on the change prediction value and product information  131  has not been set until the purchase recommendation interval has elapsed from the previous purchase-recommended date, a purchase recommendation processing unit  14  sets the day on which the purchase recommendation interval elapses, as the purchase-recommended date. 
     Since, for example, the sole of the shoe is worn out as the shoe is used, it is preferable even for a user at an age with little change in the foot size to periodically purchase shoes for replacement. Even when the purchase-recommended date based on the change prediction value and the product information  131  has not been set until the purchase recommendation interval determined on the basis of the age  111 A of the user has elapsed from the previous purchase-recommended date, the shoe purchase recommendation device  10 F according to the sixth embodiment sets the day on which the purchase recommendation interval elapses, as the purchase-recommended date, and thus can recommend the purchase of shoes at an appropriate timing even for the user at an age with little change in the foot size. Meanwhile, when a child whose foot size changes in a short period of time, particularly a child in a growth period, is the user, the purchase of shoes at an appropriate timing can be recommended because the purchase-recommended date is set on the basis of the change prediction value of the foot size and the product information  131 . 
     Seventh Embodiment 
       FIG.  14    is a diagram illustrating a configuration of a shoe purchase recommendation device according to a seventh embodiment of the present invention. A shoe purchase recommendation device  10 G according to the seventh embodiment is different from the shoe purchase recommendation device  10 A according to the first embodiment in that stock information  131 F indicating whether or not the shoes are in stock is included in product information  131 . 
     In the shoe purchase recommendation device  10 G according to the seventh embodiment, after selecting candidates for the purchase-recommended product on the basis of the foot size change prediction value and the product information  131 , a purchase recommendation processing unit  14  confirms the presence or absence of stock on the basis of the stock information  131 F and determines the purchase-recommended product from among the shoes in stock. 
     Since the purchase-recommended product is determined from among the shoes in stock, the shoe purchase recommendation device  10 G according to the seventh embodiment can avoid the occurrence of a situation in which the shoes recommended to purchase are out of stock and the user is not allowed to purchase the shoes recommended to purchase. 
     The shoe purchase recommendation devices  10 A,  10 B,  10 C,  10 D,  10 E,  10 F, and  10 G according to each of the above embodiments are preferred when a child whose foot size changes in a short period of time is a user, but can also recommend an adult user to purchase shoes at an appropriate timing. 
     Next, a hardware configuration of the shoe purchase recommendation devices  10 A,  10 B,  10 C,  10 D,  10 E,  10 F, and  10 G according to each of the above embodiments will be described.  FIG.  15    is a diagram illustrating a hardware configuration example of the shoe purchase recommendation devices according to the first to seventh embodiments.  FIG.  15    illustrates a hardware configuration in a case where the functions of the shoe purchase recommendation devices  10 A,  10 B,  10 C,  10 D,  10 E,  10 F, and  10 G are implemented by using hardware that executes a program. 
     The shoe purchase recommendation devices  10 A,  10 B,  10 C,  10 D,  10 E,  10 F, and  10 G include a processor  81  that executes various sorts of processing, a memory  82  that is a built-in memory, and a storage device  83  that stores information. The processor  81  reads the program stored in the storage device  83  into the memory  82  and executes the read program. The user data storage unit  11  and the product information storage unit  13  are implemented by the storage device  83 . 
     As described above, the shoe purchase recommendation devices  10 A,  10 B,  10 C,  10 D,  10 E,  10 F, and  10 G according to the present invention include: the user data storage unit  11  that stores the user data  111  including at least the age  111 A and the foot size measurement value  111 B of a user; the foot size change prediction unit  12  that calculates the change prediction value of the foot size of the user on the basis of the user data  111 ; the product information storage unit  13  that stores the product information  131  including the shoe size  131 A; the purchase recommendation processing unit  14  that determines the purchase-recommended date and the purchase-recommended product of shoes on the basis of the change prediction value and the product information  131 ; and the screen display processing unit  15  that performs processing of displaying the purchase-recommended date, the purchase-recommended product, and the measurement-recommended date for the foot size, in which the screen display processing unit  15  emphasizes and displays the purchase-recommended date and the purchase-recommended product when the number of days until the purchase-recommended date becomes equal to or less than a predetermined number of days. Accordingly, the shoe purchase recommendation devices  10 A,  10 B,  10 C,  10 D,  10 E,  10 F, and  10 G according to the present invention is capable of notifying the user of the purchase-recommended date, which is an appropriate timing for purchasing shoes. 
     In addition, the height  111 G and the weight  111 H of the user are included in the user data  111 , and the foot size change prediction unit  12  calculates the change prediction value using the age  111 A, the height  111 G, and the weight  111 H of the user and the foot size measurement value  111 B at the time point of the age designated by the user, whereby the user is allowed to be notified of the purchase-recommended date in consideration of the physique of the user. 
     In addition, the screen display processing unit  15  emphasizes and displays the purchase-recommended date and the purchase-recommended product with the modal window, whereby it can be made difficult for the user to overlook the display for recommending the purchase of shoes. 
     In addition, when the number of days until the purchase-recommended date becomes equal to or less than a predetermined number of days, the screen display processing unit  15  emphasizes and displays the purchase-recommended date and the purchase-recommended product by increasing the proportion occupied by the display part of the purchase-recommended date and the purchase-recommended product, whereby it can be made difficult for the user to overlook the display for recommending the purchase of shoes. 
     In addition, the purchase recommendation processing unit  14  determines the purchase-recommended products by a preset number of two or more, whereby the user can be enabled to select shoes suited to the own preference of the user, from among a plurality of purchase-recommended products. 
     In addition, the designated genre  111 D, which is a sports genre designated by the user, is included the user data  111 , the application genre  131 C, which is a sports genre in which the shoes are used, is included the product information, and the purchase recommendation processing unit  14  determines the purchase-recommended product by prioritizing the shoes of which the application genre  131 C matches the designated genre  111 D, from among the shoes fitting to the change prediction value, whereby the purchase of the shoes for use in the sports genre designated by the user can be recommended at an appropriate timing. 
     In addition, the designated color  111 E designated by the user is included in the user data  111 , the shoe color  131 D is included in the product information  131 , and the purchase recommendation processing unit  14  determines the purchase-recommended product by prioritizing the shoes of the shoe color  131 D matching the designated color  111 E, from among the shoes fitting to the change prediction value, whereby the purchase of the shoes of the color suited to the taste of the user can be recommended at an appropriate timing. 
     In addition, the designated genre  111 D, which is a sports genre designated by the user, and the designated color  111 E designated by the user are included the user data, the application genre  131 C, which is a sport genre in which the shoes are used, and the shoe color  131 D are included in the product information  131 , and the purchase recommendation processing unit  14  selects the purchase-recommended candidate collection by prioritizing the shoes of which the application genre  131 C matches the designated genre  111 D, from among the shoes fitting to the change prediction value, and determines the purchase-recommended product by prioritizing the shoes of the shoe color  131 D matching the designated color  111 E from the purchase-recommended candidate collection, whereby the purchase of the shoes for the sports genre designated by the user and of the color suited to the taste of the user can be recommended at an appropriate timing. 
     In addition, when there are no shoes of the color matching the designated color  111 E, the purchase recommendation processing unit  14  determines the purchase-recommended product by prioritizing the shoes of the predetermined approximate color associated with the designated color  111 E, whereby it becomes easy for the user to purchase the shoes of a similar color even if the color does not completely match the color designated by the user. 
     In addition, when there are no shoes for the application genre matching the designated genre  111 D, the purchase recommendation processing unit  14  determines the purchase-recommended product by prioritizing the shoes for a predetermined similar genre, which is a sports genre similar to the designated genre  111 D, whereby the purchase of the shoes for sports that are close in form of competition to the sports genre designated by the user can be recommend at an appropriate timing. 
     In addition, the sporting ability measurement value  111 F, which is a measurement result for the sporting ability of the user, is included in the user data  111 , information on the desired sporting ability value  131 E indicating the sporting ability coupled with each pair of shoes is included in the product information, and the purchase recommendation processing unit  14  determines the purchase-recommended product by prioritizing the shoes of which the desired sporting ability value  131 E is equal to or less than the sporting ability measurement value  111 F, from among the shoes fitting to the change prediction value, whereby the purchase of the shoes suited to the sporting ability of the user can be recommended at an appropriate timing. 
     In addition, the purchase recommendation interval determination unit  16  that determines the purchase recommendation interval on the basis of the age of the user is included, and when the purchase-recommended date based on the change prediction value and the product information has not been set until the purchase recommendation interval has elapsed from the previous purchase-recommended date, the purchase recommendation processing unit  14  sets the day on which the purchase recommendation interval elapses, as the purchase-recommended date, whereby the purchase of shoes can be recommended at an appropriate timing even for the user at an age with a small change in the foot size. 
     In addition, the stock information  131 F indicating whether or not the shoes are in stock is included in the product information, and the purchase recommendation processing unit  14  determines the purchase-recommended product from among the shoes in stock, whereby the purchase of the shoes that are not out of stock can be recommended to the user. 
     A shoe purchase recommendation device according to the present invention has an effect of enabling to notify a user of a purchase-recommended date, which is an appropriate timing for purchasing shoes. 
     The configurations indicated in the above embodiments illustrate examples of the content of the present invention and can be combined with another known technique. A part of the configurations can be omitted or altered without departing from the gist of the present invention.