JP7609604B2 - Computer system, program, and method - Google Patents

Description

One aspect of the present disclosure relates to a computer system, a processing method, a program, and/or a data structure.

Patent Document 1 describes an information processing server that acquires an anonymized point on a route that is close to the end of the route specified by the movement history information, and performs an anonymization process on the movement history information by excluding the movement history information from the end of the route to the anonymized point.

Patent No. 6316597

One aspect of the present disclosure aims to appropriately anonymize a user's travel route.

A computer system according to an aspect of the present disclosure includes a processor. The processor sets an abstraction flag included in map data indicating a combination of a map element and an abstraction flag indicating whether route data is abstracted so that a specific individual cannot be identified, based on whether a predetermined condition indicating that an individual may be identified from the route data is satisfied. The processor generates abstract route data by abstracting original route data indicating a user's travel route based on the map data .

FIG. 1 is a diagram illustrating an example of an application of an information management system according to an embodiment. FIG. 2 is a diagram illustrating an example of a hardware configuration of a computer used in the information management system according to the embodiment. FIG. 2 is a diagram illustrating an example of a functional configuration of an information management system according to an embodiment. FIG. 1 is a diagram illustrating an example of a map network. FIG. 2 is a diagram showing an example of data items of map data. FIG. 1 is a diagram showing an example of a transportation hub. FIG. 2 is a diagram showing an example of map data showing transportation nodes. 13 is a flowchart illustrating an example of a process for setting an abstraction flag of a map element. 13 is a flowchart illustrating an example of a process for setting an abstraction flag of a link. 13 is a flowchart illustrating an example of a process for setting an abstraction flag of a link. FIG. 11 illustrates an example of a process for setting an abstraction flag for a link. FIG. 11 is a sequence diagram illustrating an example of a process for abstracting route data.

Embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. In the description of the drawings, identical or equivalent elements are given the same reference numerals, and duplicate descriptions will be omitted.

[System Overview]
The information management system 1 according to the embodiment is a computer system that manages route data indicating a user's travel route. A travel route refers to information about travel from one point to another point in the real world, typically information about travel from a departure point to a destination. A departure point refers to a location that is set as a starting point for searching for a travel route, and a destination refers to a location that is set as an end point for the search. Both the departure point and the destination are locations that can be reference points for a route search.

In one example, the travel route can indicate not only the route from the departure point to the destination, but also the attributes of the route (hereinafter referred to as "route attributes"). The route attributes are any information that indicates the nature, characteristics, and situation of the route, or information of the user traveling along the route (age, sex, nationality, physical condition, etc.). For example, the route attributes may include at least one of the following: a means of transportation such as a means of transportation, a date and time of traveling along the route, a time or cost required to travel along the route, a route situation (e.g., traffic information), a feature related to the route (i.e., feature information), a business related to the route (i.e., business information), service information related to the route (e.g., advertising information, coupon information, etc.), information about the user traveling along the route (age, sex, nationality, body temperature, heart rate, sweat rate, blood sugar level, calorie consumption, etc.), and information about the purpose of the user traveling along the route (business, sightseeing, shopping, health, killing time, etc.). The route data is electronic data that indicates the travel route, and is typically a time-series point sequence coordinate represented by latitude and longitude information, but is not limited to this. In the route data, link IDs and node IDs obtained by matching point sequence coordinates with network data consisting of links and nodes (so-called map matching) may be used. Map matching is a technique for identifying travel routes (nodes, rings) on a network from position information such as latitude and longitude. The route data may include text data indicating the date and time (time) of travel along the route. The text data related to time may be associated with the link ID and node ID. A user is someone who provides their own route data to the information management system 1. A user may be an individual or a group consisting of multiple people.

Transportation means refers to a method for traveling. Transportation means is not limited to moving objects, but is a concept that includes methods that do not use moving objects. Transportation means may be public transportation, or a moving object operated by the user. Transportation means may be a ground or underground moving object, an air moving object, or an on-water or underwater moving object. Examples of transportation means include walking, bicycles, motorbikes, private cars, buses, taxis, conventional trains, high-speed trains, airplanes, drones, flying cars, and ferries, but of course transportation means are not limited to these.

Public transportation is defined as transportation that has fixed routes and times and is used jointly by an unspecified number of members of the public. Examples of public transportation include, but are not limited to, railways (including monorails), streetcars, route buses, airplanes, and ferries. Taxis are not public transportation.

The type of travel route indicated by the route data is not limited. The route data may indicate a travel route searched as a candidate, a travel route selected by the user, or a travel route actually used by the user. In this disclosure, a travel route searched as a candidate is referred to as a "candidate route," a travel route selected by the user from one or more candidate routes is referred to as a "planned route," and a travel route actually used by the user is referred to as an "actual route." One travel route may correspond to two or more of a candidate route, a planned route, and an actual route.

A feature is any tangible or intangible object that exists on the ground. A feature may be natural or man-made. For example, features may include mountains, farmland, residential areas, vacant lots, rivers, lakes, oceans, tourist sites, roads, railways, buildings, parks, towers, traffic lights, railroad crossings, pedestrian crossings, footbridges, buoys, etc. Examples of intangible features include areas set up for any purpose (e.g. no photography zones, temporary no-entry zones, etc.), areas where events are held, meeting places, photo spots, etc. Naturally, the types of features are not limited to these.

The route data of one or more users managed by the information management system 1 may be used for any purpose. For example, the route data may be used for various purposes that are useful for maintaining or improving people's lives or the global environment, such as "Mobility as a Service (MaaS)", urban planning, traffic planning, environmental measures, disaster prevention measures, crime prevention measures, demand forecasting, marketing, and people flow analysis. The route data may be used by any business operator and other users. Examples of businesses include operators of various transportation facilities such as railways, ropeways, buses, taxis, airplanes, drones, and ships, rental businesses of various means of transportation such as automobiles and bicycles, vehicle dispatch service operators, businesses that operate various facilities such as shopping, restaurants, and parking lots, businesses that provide various information such as advertisements and coupons, payment operators, and various organizations of the country or local government. Business operators may also include sole proprietors.

However, the route data may contain or indicate the user's personal information. Here, personal information refers to information about a living individual that can identify a specific individual. If route data that can identify an individual is available to an operator, the operator may grasp personal information such as the behavior of a specific individual based on the route data. The information management system 1 abstracts the route data provided by the user so that the user is not identified by the route data, while retaining a degree of specificity that can be used for various purposes that are useful for maintaining or improving people's lives or the global environment as big data related to the user's movement (i.e., the user's personal information is not identified from the route data, but the analytical utility value as data is retained). "Abstracting route data" refers to a process of discarding some of the concrete information elements contained in the route data and redefining the route data to indicate a more conceptual meaning. In short, "abstracting route data" refers to a process of intentionally obscuring the information elements or meaning contained in the route data. Although it is not possible to identify an individual from the abstracted route data, the analytical utility value as data remains in the route data. Route data abstraction is the process of converting route data for use by users so that it cannot identify specific individuals, so it can also be called "anonymizing route data."

In this disclosure, the route data to be abstracted is also referred to as "original route data", and the abstracted route data is also referred to as "abstract route data". In addition, the travel route indicated by the original route data is also referred to as the "original travel route", and the travel route indicated by the abstract route data is also referred to as the "abstract travel route". For this reason, when the original route data is electronic data in which link IDs and node IDs are associated with the passage times, abstract route data may be generated in which only the passage times are abstracted (i.e., temporal abstraction). Alternatively, only the link IDs and node IDs may be abstracted (i.e., spatial abstraction), or both temporal abstraction and spatial abstraction may be performed.

In one example, the information management system 1 may serve as a platform that collectively controls or manages route data that may be used for various purposes. In this regard, the administrator or operator of the information management system 1 may be a platformer. In one example, the information management system 1 may provide abstract route data to any business operator or other user. The business operator may carry out any business based on the abstract route data. The abstract route data may be shared by multiple businesses or other users.

[System Configuration]
FIG. 1 is a diagram showing an example of application of an information management system 1. In one example, the information management system 1 includes a platform server 10 and one or more user terminals 20. The platform server 10 and each user terminal 20 can transmit and receive data to and from each other via a communication network NW. The platform server 10 can access a group of databases 30 via the communication network NW to read and write data. At least a portion of the data stored in the group of databases 30 can be accessed by one or more business servers 40 via the communication network NW. The platform server 10 can also access an external system 50 via the communication network NW to obtain required information.

The platform server 10 is a computer that collects route data. There are no limitations on the computer that functions as the platform server 10. In one example, the platform server 10 is configured by a large computer such as a business server. The platform server 10 may be configured by one or more computers. When multiple computers are used, these computers are connected to each other via a communication network to logically configure one platform server 10.

The user terminal 20 is a computer operated by a user. In one example, the user terminal 20 can access the abstract route database 32 described below to obtain other users' already-prepared abstract route data. The user terminal 20 may be a fixed terminal or a mobile terminal. Examples of the user terminal 20 include devices such as mobile phones, smartphones, tablet terminals, wearable terminals, and personal computers. However, the types of user terminals 20 are not limited to these. The user terminal 20 may be a device consisting of a single housing, or may be composed of multiple devices. For example, the user terminal 20 may be a combination of a wearable terminal and a smartphone. There is no limit to the number of user terminals 20 that access the information management system 1.

The database group 30 is a collection of databases that store data used in the information management system 1. In one example, the database group 30 includes a map database 31 and an abstract route database 32. Each database may be constructed as part of the information management system 1, or may be provided in a computer system separate from the information management system 1. The map database 31 is a non-transient storage medium or storage device that permanently stores map data indicating map elements that make up a map. The abstract route database 32 is a non-transient storage medium or storage device that permanently stores abstract route data.

The business operator server 40 is a computer managed or operated by a business operator. In one example, the business operator server 40 can access the abstract route database 32 to obtain abstract route data. There is no limitation on the computer that functions as the business operator server 40. For example, the business operator server 40 may be configured as a large computer such as a business server, or may be configured as a personal computer. There is no limitation on the number of business operator servers 40 that access the information management system 1.

The external system 50 is a computer system that exists outside the information management system 1. The specific configuration and functions of the external system 50 are not limited. For example, the external system 50 is a computer system that publishes content posted on a specific website on the Internet. Typically, the website relates to a social networking service (SNS), and the content is photos, videos, text, or a combination of two or more of these. In this disclosure, a person who posts content on a website is called a "contributor."

In one example, in the information management system 1, the user terminal 20 abstracts the original route data to generate abstract route data. In other words, the user terminal 20 converts the original route data into abstract route data. The user terminal 20 transmits the abstract route data to the platform server 10. The timing of transmission is typically after the user arrives at the destination, but may be before the user arrives at the destination. If the type of the travel route is a candidate route or a planned route, the timing of transmission may be before the user starts traveling from the departure point. Even if the type of the travel route is an actual route, the user terminal 20 may transmit the actual route up to the middle of the way to the destination at that timing. In one example, the platform server 10 registers the abstract route data in the abstract route database 32. Therefore, the user terminal 20 may transmit the abstract route data to the platform server 10 and cause the platform server 10 to register the abstract route data in the abstract route database 32. Since the user terminal 20 does not generally transmit the original route data to the platform server 10 except when based on the user's will, the platform server 10 cannot access the original route data. Therefore, the platform server 10, the business server 40, and other user terminals 20 can use the abstract route data, but cannot refer to or use the original route data. This mechanism prevents the operators of the platform server 10 and the business server 40, or other users of the user terminal 20, from learning the user's personal information from the route data.

In another example, in the information management system 1, the platform server 10 abstracts the original route data to generate abstract route data, and registers the abstract route data in the abstract route database 32. In this example, the business server 40 and other user terminals 20 can still use the abstract route data, but cannot refer to or use the original route data. Therefore, the operator of the business server 40 or other users who use the user terminals 20 cannot ascertain personal information of a certain user from the route data.

In this way, in the information management system 1, the user terminal 20 may convert the original route data into abstract route data, or the platform server 10 may perform the conversion. In other words, in the information management system 1, the computer that abstracts the route data is not limited.

As yet another example, if based on the user's wishes, the user terminal 20 may transmit original route data to the platform server 10. In this case, the operators of the platform server 10 and the business server 40, or other users of the user terminal 20, can ascertain the user's personal information from the route data and perform useful data analysis in comparison with the case of abstract route data. In this case, a certain economic benefit may be returned to the user who provided the original route data by the operator of the business server 40 via the platform server 10.

2 is a diagram showing an example of the hardware configuration of a computer 110 used in the information management system 1. For example, the computer 110 has a control circuit 100. In one example, the control circuit 100 has one or more processors 101, a memory 102, a storage 103, a communication port 104, and an input/output port 105. The processor 101 executes an operating system and application programs. The storage 103 is composed of a storage medium such as a hard disk, a non-volatile semiconductor memory, or a removable medium (e.g., a magnetic disk, an optical disk, etc.), and stores the operating system and application programs. The memory 102 temporarily stores a program loaded from the storage 103 or a calculation result by the processor 101. The processor 101 functions as an individual functional module by executing a program in cooperation with the memory 102. The communication port 104 performs data communication with other devices via the communication network NW according to instructions from the processor 101. The input/output port 105 performs input/output of electrical signals between input/output devices (user interfaces) such as a keyboard, mouse, monitor, and touch panel in accordance with instructions from the processor 101.

The installed hardware modules may vary depending on the type of computer. For example, the CPU, memory, network card, and other modules installed in the platform server 10 may be more powerful than those in the user terminal 20. A keyboard and mouse are generally used as input devices for the platform server 10, and a monitor is used as the output device. If the user terminal 20 is a personal computer, a keyboard and mouse are generally used as input devices, and a monitor is used as the output device. If the user terminal 20 is a mobile terminal, a touch panel is generally used as the input/output device.

Figure 3 is a diagram showing an example of the functional configuration of the information management system 1. More specifically, Figure 3 shows an example of the functional configuration of the platform server 10 and the user terminal 20. In this example, the user terminal 20 converts the original route data into abstract route data.

The platform server 10 has the following functional modules: a search unit 11, a map management unit 12, and a registration unit 13. The search unit 11 is a functional module that searches for travel routes in response to a request from the user terminal 20. The map management unit 12 is a functional module that manages the map data in the map database 31. The registration unit 13 is a functional module that registers abstract route data in the abstract route database 32.

The user terminal 20 includes functional modules including a route acquisition unit 21, a map storage area 22, a map update unit 23, an abstraction unit 24, and a transmission unit 25. The route acquisition unit 21 is a functional module that acquires original route data from a route search function 28 or a route tracing function 29. The route search function 28 cooperates with the search unit 11 of the platform server 10 to display information on a travel route (i.e., a candidate route) that matches the search conditions set by the user on the user terminal 20. The route tracing function 29 acquires the history of the current position of the user terminal 20 as a past route. In one example, the route tracing function 29 uses a global positioning system (GPS) function. Alternatively, the route tracing function 29 may acquire the past route by other means such as mobile phone base station data, WiFi (registered trademark) access point data, and transportation IC card data. The map storage area 22 is a functional module (storage area) that permanently stores a copy of at least a part of the master of the map data. The map update unit 23 is a functional module that aligns the copy with the master. The abstraction unit 24 is a functional module that abstracts the original route data to generate abstract route data. The transmission unit 25 is a functional module that transmits the abstract route data to the platform server 10.

[Map data]
The map data is used, for example, for route searches. The data structure of the map data is not limited. The types and representation methods of map elements shown by the map data are not limited and may be designed according to any policy. Examples of map elements include nodes, links, polygon nodes, and POIs (Points of Interest).

A node is a location that characterizes a route, and more specifically, a location where the way a moving object moves (e.g., direction, speed, etc.) can be changed, or where the way of moving changes (e.g., transfer points such as stations, bus stops, and parking lots, intersections, etc.).

A link is a virtual line that is set to indicate a route, and connects adjacent nodes. The shape of a link may be straight or curved, or it may be a combination of straight and curved lines. On the ground, the shape of a link may depend on the shape of a road or a track such as a railway. There may be multiple links connecting two nodes. For example, two nodes may be connected by both a railway-related link and a road-related link.

A polygon node is a surface that indicates a specific geographical area that extends two-dimensionally, and is represented as a two-dimensional closed space surrounded by multiple links. The shape of a polygon node is not limited in any way. Examples of geographical areas that can be represented by a polygon node include parks, plazas, pedestrian decks, concourses within a station, the grounds of a facility or building, floors of a facility or building, and underground malls. However, the geographical area is not limited in any way. A polygon node may or may not be divided into multiple small areas.

Figure 4 shows an example of a map network represented by map data. In this example, map network 150 includes multiple nodes 151, multiple links 152, and one polygon node 153. Polygon node 153 consists of three small regions 153a, 153b, and 153c. The positions at which nodes, links, and polygon nodes are set are not limited, and for example, nodes, links, and polygon nodes can be set on the ground, underground, in the air, on water, or underwater. Correspondingly, the map network can also be set on the ground, underground, in the air, on water, or underwater.

A POI is a specific point on a map, typically corresponding to a specific feature. Any point or feature can be a POI, such as a residence (private residence or apartment complex) or public facility. A residence is a building in which people live. A private residence is a residence in which one family lives on a single lot. An apartment complex is a residence in which multiple families live, and thus includes a two-family home. A public facility is a facility that can be used by an unspecified number of people or a specified number of people.

In one example, the map data includes node data indicating multiple nodes, link data indicating multiple links, polygon node data indicating at least one polygon node, and POI data indicating multiple POIs. The structure of each of these data will be described with reference to FIG. 5. FIG. 5 is a diagram showing an example of data items of map data. In this example, map data 200 includes node data 201, link data 202, polygon node data 203, and POI data 204.

In one example, the node data 201 includes a node ID, coordinates, and node attributes as data items. The node ID is an identifier that uniquely identifies each node. The coordinates are values that indicate the two-dimensional or three-dimensional geographical position of the node. The method of setting the coordinates is not limited, and for example, the coordinates may be expressed using latitude and longitude, or may be set according to any other coordinate system. The node attributes are any information that represents the nature, characteristics, or status of the node. For example, the node attributes may include feature information regarding a feature associated with the node, or may include business information regarding a business associated with the node. The node attributes may include an abstraction flag that indicates whether to abstract the node.

In one example, the link data 202 includes a link ID, a first node ID, a second node ID, and a link attribute as data items. The link ID is an identifier that uniquely identifies each link. The first node ID and the second node ID are both node IDs that identify the nodes located at the ends of the link. The link attribute is any information that represents the nature, characteristics, or status of the link. For example, the link attribute may include at least one of a means of transportation such as a transportation facility, a time or cost required to travel the link, a link status (e.g., traffic information), a feature related to the link (i.e., feature information), a business related to the link (i.e., business information), and service information related to the link (e.g., advertising information, coupon information, etc.). The link attribute may include an abstraction flag that indicates whether the link is abstracted.

In one example, the polygon node data 203 includes a polygon node ID, a group of related node IDs, a group of related link IDs, and polygon node attributes as data items. The polygon node ID is an identifier that uniquely identifies each polygon node. The group of related node IDs is a group of node IDs that indicate a group of nodes located on the outer edge of the polygon node. The group of related link IDs is a group of link IDs that indicate a group of links that form the outer edge of the polygon node. The polygon node attributes are any information that represents the nature, characteristics, or status of the polygon node. For example, the polygon node attributes may include at least one of the representative coordinates of the polygon node, feature information regarding a feature related to the polygon node, and business information regarding a business related to the polygon node. The polygon node attributes may include an abstraction flag that indicates whether or not to abstract the polygon node. When the polygon node is divided into a plurality of small regions, the polygon node data 203 further includes a small region ID and a small region attribute as data items. The small region ID is an identifier that uniquely identifies each small region. The small region attribute is any information that represents the nature, characteristics, or status of the small region. The small area attributes may include at least one of the following: representative coordinates of the small area, boundary information indicating the boundary of the small area, feature information regarding features related to the small area, and business information regarding businesses related to the small area. The small area attributes may include an abstraction flag indicating whether to abstract the small area.

In one example, the POI data 204 includes a POI_ID, an arrival point, and a POI attribute as data items. The POI_ID is an identifier that uniquely identifies each POI. The arrival point indicates the link (road) to which the entrance/exit of the POI is connected, and the link ID of the link is set in this data item. When the POI is set as the destination in a route search, for example, the position of the link indicated by this arrival point is processed as the position of the destination. The arrival point is an example of a data item that indicates the connection between the POI and the link. The POI attribute is any information that represents the nature, characteristics, or status of the POI. In one example, the POI attribute may include the name, type, feature information, and available time (or unavailable time). The name is the official name or common name of the POI, and is represented by, for example, the name of the head of the household, the house name, the building name, etc. The type refers to the type (category) to which the POI belongs, and indicates, for example, whether it is personal property or public property. Feature information is any information about a feature related to a POI. Available time (or unavailable time) refers to the time range during which a POI can be used (or unavailable). The length of the available time (or unavailable time) is not limited and may be any length, such as a time period, date, or day of the week. POI attributes may include an abstraction flag that indicates whether or not the POI is abstracted.

In one example, the map data further includes data indicating transport nodes and transport facilities. In this case, the node attributes may include information about the transport nodes or transport facilities.

A transportation hub is a place where a change in transportation mode is implemented (i.e., a place where the transportation mode changes). More specifically, a transportation hub is a place where multiple transportation modes of the same or different types are connected. A transportation hub includes multiple transportation facilities.

"Change of transportation means" refers to changing from one transportation means to another. Since the transportation means are not limited, the change of transportation means is also not limited. Transferring from one transportation means to another is an example of a change of transportation means. Examples of a change of transportation means include transferring from a taxi to a conventional line, transferring from one line (railroad line, bus line, etc.) to another line (railroad line, bus line, etc.), changing from a private car to walking, changing from walking to a conventional line, etc.

A transportation facility is a facility used by a user to change the means of transportation. The transportation facility is processed by the information management system 1 as an element that constitutes a transportation node. A transportation facility can be a type of node. Examples of transportation facilities include, but are not limited to, stations, bus stops, taxi stands, ports, airports, heliports, rental car offices, bicycle rental ports, parking lots, and bicycle parking lots. One transportation facility may be associated with multiple transportation nodes. Therefore, the transportation nodes and transportation facilities have a many-to-many relationship (in other words, an M:N relationship). At each transportation node, one transportation facility is set to represent the transportation node. In this disclosure, the representative transportation facility is referred to as a "representative facility." In addition, in this disclosure, transportation facilities other than the representative facility at each transportation node are referred to as "constituent facilities."

The representative facility may be set by any method. For example, the representative facility may be a transportation hub or a facility that plays the most central role in a particular area, a transportation facility with the most users, or a transportation facility that serves as a landmark.

Constituent facilities may also be set according to any policy. When a certain transportation facility is to be assigned as a constituent facility to one of the transportation nodes, the representative facility closest to the transportation facility may be identified, and the transportation facility may be added as a constituent facility to the same transportation node as the identified representative facility. Alternatively, the transportation node to which the transportation facility is to be assigned may be determined based on the usage history of users who use different transportation means or topographical relationships (for example, constituent facilities may be determined so that a certain transportation facility is not assigned to a representative facility across a river).

Map data showing transport nodes and transport facilities will be described with reference to Figures 6 and 7. Figure 6 is a diagram showing an example of a transport node. Figure 7 is a diagram showing an example of map data showing a transport node, and corresponds to Figure 6.

Figure 6 shows a schematic diagram of a map 300 including a subway 310, a conventional line 320, a road network 330, and a road network 340. In the map 300, white circles represent transportation facilities, and dashed lines represent transportation nodes. Although two transportation nodes, hubs Ha and Hb, are illustrated in Figure 6, it should be noted that there may be more transportation nodes in the map 300. In this example, the hub Ha is composed of a subway station A, a conventional line station A, and a bus stop Bx. At the hub Ha, people can change their transportation means in various ways, such as transferring between the subway, conventional line, and bus, or getting off the subway, conventional line, or bus and walking. The hub Hb is composed of a conventional line station B and a bus stop By. At the hub Hb, people can change their transportation means in various ways, such as transferring between the conventional line and the bus, or walking to the station and taking the conventional line or the bus.

Figure 7 shows map data 210 for hubs Ha and Hb. This map data 210 includes a transportation node table 211, a transportation facility table 212, and a transfer table 213.

The transportation node table 211 is a data table that stores transportation node data that indicates information about transportation nodes. In one example, each record of the transportation node data includes a transportation node ID that uniquely identifies an individual transportation node, the name of the transportation node (transport node name), and an abstraction flag. The abstraction flag indicates whether or not the entire transportation node is to be abstracted.

The transportation facility table 212 is a data table that stores transportation facility data that indicates information about transportation facilities. In one example, each record of the transportation facility data includes a transportation facility ID that uniquely identifies each transportation facility, the name of the transportation facility (facility name), a transportation node ID corresponding to the transportation facility, a representative flag, and an abstraction flag. The representative flag is information that indicates whether the transportation facility is a representative facility or a constituent facility, and is indicated by a binary value. In one example, the representative flag is either "1" that indicates a representative facility, or "0" that indicates a constituent facility. The example in Figure 7 indicates that station A on a conventional line is a representative facility of hub Ha, and station B is a representative facility of hub Hb. The abstraction flag indicates whether the transportation facility is abstracted or not.

The transfer table 213 is a data table that stores transfer data indicating information regarding transfers at transportation nodes. In one example, each record of the transfer data includes a transfer ID that uniquely identifies an individual transfer method, IDs of two transportation facilities used for the transfer (a first transportation facility ID and a second transportation facility ID), and a travel cost. The travel cost is the load imposed on travel and is expressed, for example, in terms of travel time. The example in FIG. 7 shows that at hub Ha, transfers can be made between conventional lines, subways, and buses at will, and at hub Hb, transfers can be made between conventional lines and buses.

The transport facility table 212 is associated with the transport node table 211 by a transport node ID, and this relationship makes it possible to identify transport facilities belonging to a transport node. The transfer table 213 is associated with the transport facility table 212 by two transport facility IDs, and this relationship makes it possible to identify possible transfer methods at a transport node.

In one example, an abstraction flag is associated with any one or more map elements selected from nodes, links, polygon nodes, small areas, POIs, traffic nodes, and traffic facilities. In this embodiment, the abstraction flag takes one of the following values: a value "1" indicating that the route data to be processed (latitude and longitude, node, link, polygon node, small area, POI, traffic node, or traffic facility) is to be abstracted, and a value "0" indicating that the route data is not to be abstracted. However, the method of expressing the abstraction flag is not limited to this example, and may be designed according to any policy. As described above, the node attribute may include information on the traffic node or traffic facility. Therefore, the abstraction flag of the node data may indicate whether or not the traffic node or traffic facility is to be abstracted, and in this case, the traffic node data and the traffic facility data may not include an abstraction flag. In any case, the map data indicates a combination of the map element and the abstraction flag indicating whether or not the route data is to be abstracted.

Individual data items of the map data may be set statically or dynamically. "Statically set" means that a value is set in advance and the setting will not change without human intervention. On the other hand, "dynamically set" means that a value can be changed without human intervention in response to any event. Dynamic setting is achieved by running a program that controls a given data item on a specific computer. Dynamic setting may be performed by the information management system 1 or by another computer system.

[Route data]
The data structure of the route data is not limited. For example, the route data may be represented by a plurality of node IDs and a plurality of link IDs. More specifically, the route data may be represented by node IDs of nodes corresponding to transportation facilities or transportation nodes, and link IDs of links connecting the nodes (i.e., between transportation facilities or between transportation nodes). As described above, a travel route can indicate route attributes, so the route data may include data items corresponding to the route attributes. For example, the route data may indicate the date and time of travel on the route (referred to as "travel date and time" in this disclosure). Examples of travel date and time include departure date and time, passing date and time, transfer date and time, or arrival date and time at each node. However, the types of travel date and time are not limited to these. The travel date and time indicate the scheduled date and time for candidate routes and planned routes, and indicate the actual date and time for actual routes. In another example, the route data may indicate the expected or actual amount of transportation costs on the travel route. This transportation cost may be indicated for each transportation means, or may be indicated as a total amount for the entire travel route.

At least a portion of the abstract route data may be represented by node IDs corresponding to a plurality of abstracted nodes and link IDs corresponding to a plurality of abstracted links. In another example, the abstract route data may represent an abstracted travel date and time. Each record of the abstract route data stored in the abstract route database 32 includes a route ID, which is an identifier that identifies an individual travel route or a group of travel routes.

For both the sample route data and the abstract route data, the method of setting the route ID is not limited. For example, one route ID may be set for one candidate route, one planned route, or one actual route. Alternatively, one route ID may be set for a group of travel routes (for example, a collection of multiple travel routes extracted in one search process).

[System procedure]
(Setting the abstraction flag)
FIG. 8 is a flowchart showing an example of a process for setting an abstraction flag for each map element as a process flow S1. In step S11, the map management unit 12 refers to the map database 31 and selects one map element to be processed. For example, the map management unit 12 selects one node, one link, one polygon node, one POI, one traffic hub, or one traffic facility. In step S12, the map management unit 12 sets the abstraction flag for the map element based on a predetermined rule. In this embodiment, the map management unit 12 sets the abstraction flag to either "1" or "0". The rule for setting the abstraction flag is not limited and may be designed according to any policy. As shown in step S13, the map management unit 12 repeats the processes of steps S11 and S12 until the abstraction flag is set for all map elements to be processed.

Various examples of setting the abstraction flag (step S12) will be described. For example, the map management unit 12 may set the abstraction flags of nodes, polygon nodes, small areas, and POIs corresponding to houses to "1," and set the abstraction flags of nodes, polygon nodes, small areas, and POIs corresponding to public facilities to "0."

In one example, the map management unit 12 may set the abstraction flag of a link according to the type of transportation network corresponding to the link. For example, the map management unit 12 may set the abstraction flag of a link corresponding to a major transportation network such as a railway, expressway, national road, prefectural road, etc. to "0", and set the abstraction flag of a link corresponding to a link that does not constitute a major transportation network (e.g., a municipal road, a private road, etc.) to "1".

In one example, the map management unit 12 may set the abstraction flag of a link based on the type of POI associated with the link. Here, "POI associated with a link" and "link associated with a POI" indicate that the link and the arrival point of the POI are connected to each other. For example, the map management unit 12 may set the abstraction flag of a link that is not associated with a public facility to "1" and the abstraction flag of a link that is associated with at least one public facility to "0". Alternatively, the map management unit 12 may set the abstraction flag of the link based on the number of POIs associated with the link. For example, the map management unit 12 may set the abstraction flag of a link with the number of associated houses less than a threshold Ta to "1" and the abstraction flag of a link with the number equal to or greater than the threshold Ta to "0". In one example, the map management unit 12 counts one apartment building as one house. Alternatively, the map management unit 12 may set the abstraction flag of a link where the number of associated households is less than the threshold Tb to "1" and set the abstraction flag of a link where the number is equal to or greater than the threshold Tb to "0". As the number of households in an apartment building, the map management unit 12 may count the number of households actually residing there, or the number of households available for occupancy. The specific values of the thresholds Ta and Tb are not limited and may be set according to any policy. The map management unit 12 may set the abstraction flag of the node based on the type of POI associated with the node.

In one example, the map management unit 12 may set an abstraction flag for a link based on the number of people who passed through the link in a predetermined time span. Specifically, the map management unit 12 may set the abstraction flag for a link whose number of people passing through is less than a threshold Tc to "1" and may set the abstraction flag for a link whose number of people passing through is equal to or greater than the threshold Tc to "0". There is no limitation on the means of transportation used by passersby, and for example, any mobile object or walking may be used. There is no limitation on the method of identifying the number of people passing through the link. The map management unit 12 may identify the number of people passing through the link based on content posted on the SNS. For example, the map management unit 12 may identify the number of people passing through based on at least one of the posted text and the number of posts. Alternatively, the map management unit 12 may identify the number of people passing through based on location information obtained from the GPS function of a mobile device owned by a poster of the SNS. The specific value of the threshold Tc is also not limited, and may be set according to any policy.

The map management unit 12 may set the abstraction flag for all transport nodes and transport facilities to "0". The reason for this is that transport nodes and transport facilities are generally places where an unspecified or specified number of people pass through, and therefore cannot be considered places where individuals can be identified. Of course, the map management unit 12 may set the abstraction flag for transport nodes and transport facilities to either "0" or "1" based on data such as the number of people passing through.

Figure 9 is a flowchart showing an example of a process for setting the abstraction flag for each link as process flow S2. Process flow S2 can be said to be a more specific example of process flow S1.

In step S21, the map management unit 12 refers to the map database 31 and selects one link to process.

In step S22, the map management unit 12 refers to the map database 31 to identify the POI associated with the link. Specifically, the map management unit 12 refers to the POI data to identify the POI for which the link is set as the destination point.

In step S23, the map management unit 12 determines whether the link is associated with a public facility. For example, the map management unit 12 refers to the attributes of the identified POI (e.g., type or feature information) to determine whether the POI is a public facility. If the link is not associated with a public facility, i.e., if all of the identified POIs are not public facilities (NO in step S23), the process proceeds to step S24. On the other hand, if the link is associated with a public facility, i.e., if at least one of the identified one or more POIs is a public facility (YES in step S23), the process proceeds to step S29. Even if the facility does not belong to an administrative organization such as a national or local government, if it is a facility that is supported by a franchiser's store opening plan and is typically used by an unspecified number of people (e.g., a famous convenience store chain), the map management unit 12 may consider the facility to be a public facility and execute the process from step S23 onwards.

In step S24, the map management unit 12 identifies the number of houses (or households) associated with the link. For example, the map management unit 12 counts the number of houses (or households) by referring to the attributes of the identified POI.

In step S25, the map management unit 12 determines whether the number of houses associated with the link is less than a threshold value Ta. Alternatively, the map management unit 12 determines whether the number of households associated with the link is less than a threshold value Tb. In the case of a determination based on the number of houses, if the number is less than the threshold value Ta (YES in step S25), the process proceeds to step S26, and if the number is equal to or greater than the threshold value Ta (NO in step S25), the process proceeds to step S29. In the case of a determination based on the number of households, if the number is less than the threshold value Tb (YES in step S25), the process proceeds to step S26, and if the number is equal to or greater than the threshold value Tb (NO in step S25), the process proceeds to step S29.

In step S26, the map management unit 12 identifies the number of people who have passed through the link. As described above, the map management unit 12 may identify the number of people who have passed through the link based on content posted on the SNS. Alternatively, the map management unit 12 may identify the number of people who have passed through the link based on location information obtained from the GPS function of a mobile device owned by the SNS poster.

In step S27, the map management unit 12 determines whether the number of passers-by is less than the threshold value Tc. If the number of passers-by is less than the threshold value Tc (YES in step S27), the process proceeds to step S28. On the other hand, if the number of passers-by is equal to or greater than the threshold value Tc (NO in step S27), the process proceeds to step S29.

In step S28, the map management unit 12 sets the abstraction flag of the link to "1." A link that has no public facilities, a relatively small number of existing houses (or households), and little foot traffic is a location where there is a high probability that a specific individual will be identified. Taking this into consideration, the map management unit 12 sets the abstraction flag of such a link to "1."

On the other hand, in step S29, the map management unit 12 sets the abstraction flag to "0." Links associated with public facilities, links with a relatively large number of houses (or households), and links with a lot of pedestrian traffic are all locations where the probability of identifying a specific individual is low. Taking this into consideration, the map management unit 12 sets the abstraction flags of these links to "0."

As shown in step S30, the map management unit 12 repeats steps S21 to S29 until it has set the abstraction flag for all links to be processed.

While changes to the POI associated with a link (e.g., the construction or demolition of a building) do not occur in the short term, the number of people passing through a link can change significantly over a specific period of time. For example, a particular location may attract short-term attention due to a post by an influencer, who is a person with a high level of information dissemination power on social media, and many people may visit the location. In this case, the number of people passing through a link that normally has little foot traffic may increase over a specific period of time due to its popularity.

Taking into consideration such fluctuations in the number of passers-by over a relatively short period of time, the platform server 10 may execute the process shown in FIG. 10. FIG. 10 is a flowchart showing another example of the process of setting the abstraction flag of each link as a process flow S3. In step S31, the map management unit 12 selects one link for updating the abstraction flag. For example, the map management unit 12 may select a link where there are no public facilities and the number of existing houses is less than a threshold value Ta. Alternatively, the map management unit 12 may select a link where there are no public facilities and the number of existing households is less than a threshold value Tb. Thereafter, the map management unit 12 executes steps S32 to S36, which are similar processes to steps S26 to S30. Through this series of processes, the abstraction flag of the link selected as the target for update may change from "1" to "0" or from "0" to "1" depending on the fluctuation in the number of passers-by.

Figure 11 shows an example of a process for setting a link abstraction flag. In this example, roads 401 and 402 run parallel to each other at a fixed distance, and three roads 403 to 405 run parallel to each other and connect roads 401 and 402. Road 406 runs from road 401 in the opposite direction to roads 403 to 405. Roads 401 and 402 are considered to be part of a major transportation network, while roads 403 to 406 are not. There are ten private homes along road 403, two private homes along road 404, and five private homes along road 405. There is a public facility at the end of road 406. Links 411 to 415 are set along road 401, and links 416 to 419 are set along road 402. Link 420 is set for road 403, link 421 is set for road 404, link 422 is set for road 405, and link 423 is set for road 406.

In one example, the map management unit 12 sets the abstraction flags of links 411 to 419 that make up roads 401 and 402, which are major transportation networks, to "0." If the threshold Ta for the number of houses is 10, the map management unit 12 sets the abstraction flag of link 420 (road 403), which has 10 houses, to "0." If the number of people passing through link 421 (road 404) is equal to or greater than the threshold Tc and the number of people passing through link 422 (road 405) is less than the threshold Tc, the map management unit 12 sets the abstraction flag of link 421 to "0" and the abstraction flag of link 422 to "1." The map management unit 12 sets the abstraction flag of link 423 (road 406), which has public facilities, to "0." Therefore, in the example of FIG. 11, only link 422 is abstracted.

Figure 11 shows an example of processing related to links, but the map management unit 12 may also perform similar processing for nodes.

As illustrated by the process flows S1 to S3, the abstraction flag is managed by the map management unit 12. The map management unit 12 sets or updates the abstraction flag at any time and stores the latest master of the map data in the map database 31. The map update unit 23 of the user terminal 20 downloads at least a partial copy of the latest master from the platform server 10 at any time and stores the copy in the map storage area 22. The map update unit 23 may download only map data related to a predetermined area including the user's current location, and when the user moves, download map data corresponding to the movement. This process can reduce the processing load of the user terminal 20. The method of downloading the map data is not limited and may be designed based on any policy. For example, the map management unit 12 may send a notification to the user terminal 20 indicating that the map data has been updated, and the download may be performed based on this transmission. Specifically, in response to the notification, the map update unit 23 requests the latest map data from the platform server 10 automatically or based on a user input. In response to the request, the map management unit 12 reads a copy of at least a portion of the latest master from the map database 31 and transmits the copy to the user terminal 20. The map update unit 23 stores the copy in the map storage area 22.

(Route data abstraction)
The process of abstracting route data will be described with reference to Fig. 12. Fig. 12 is a sequence diagram showing an example of the process as a process flow S4. In this example, the user terminal 20 converts the original route data into abstract route data.

In step S41, the route acquisition unit 21 of the user terminal 20 acquires the original route data. For example, the route acquisition unit 21 may acquire the original route data from the route search function 28 or the route tracing function 29.

The route acquisition unit 21 may acquire original route data indicating a candidate route or a planned route from the route search function 28. The route search function 28 transmits search conditions to the platform server 10 in response to a predetermined user operation. In addition to the departure point and destination, the search conditions may include data items such as at least one of the departure date and time and the arrival date and time, at least one intermediate stop, the means of transportation to be used, and conditions for a changed route. In the platform server 10, the search unit 11 refers to the map database 31 to search for one or more travel routes that satisfy the search request, and transmits the search results to the user terminal 20. In one example, the route search function 28 receives and displays the search results, so that the user can visually confirm the search results. The route acquisition unit 21 acquires data indicating at least one of the one or more travel routes indicated in the search results as original route data.

The route acquisition unit 21 may acquire original route data indicating the actual route from the route tracing function 29. The route tracing function 29 can acquire the history of the current position of the user terminal 20 as the actual route in response to a specific user operation. The route acquisition unit 21 acquires the data indicating the actual route as original route data.

In step S42, the abstraction unit 24 of the user terminal 20 abstracts the original route data to generate abstract route data. The abstraction unit 24 abstracts each of the one or more original route data as follows. That is, the abstraction unit 24 refers to the original route data and the map data in the map storage area 22 to determine whether or not a map element with an abstraction flag of "1" exists on the original travel route. If one or more such map elements exist, the abstraction unit 24 abstracts each of the one or more map elements to generate abstract route data. The specific method of abstracting the map elements is not limited. For example, the abstraction unit 24 may delete a map element with an abstraction flag of "1" from the original route data. Alternatively, the abstraction unit 24 may convert a first map element with an abstraction flag of "1" into a second map element with an abstraction flag of "0" and located near the first map element. Assume that the original travel route includes a first small area that belongs to a certain polygon node and has an abstraction flag of "1". Then, the polygon node further includes a second small area whose abstraction flag is "0". In this case, the abstraction unit 24 may convert the first small area into the second small area, or may convert the first small area into the polygon node. If there are no map elements to be abstracted for a certain piece of original route data, the abstraction unit 24 may process the original route data as it is as abstract route data.

In one example, the abstraction unit 24 may calculate the transportation costs, which are the fees for using the means of transportation in the original travel route, abstract the original route data while leaving the information on the transportation costs (information that simply indicates the amount) intact, and generate abstract route data corresponding to the transportation costs. In this case, the transportation costs are calculated based on the original route data, so the accuracy of the amount is guaranteed. When multiple means of transportation are used, the transportation costs may be calculated for each means of transportation. The abstraction unit 24 may output the calculated transportation cost information to the user by any method such as text or voice, and allow the user to recognize it. In response to a user operation that makes the output transportation cost information suspicious, the abstraction unit 24 may recalculate the transportation costs.

The abstraction unit 24 may output a notification to the user by any method, such as text or voice, indicating that the original route data has been abstracted. This notification may indicate at least one of the processed original route data (i.e., the original travel route) and the abstract route data (i.e., the abstract travel route). This notification can convey to the user information such as the fact that the travel route has been abstracted, and details of the travel route before or after abstraction. The abstraction unit 24 may confirm the user's clear intention when sending the abstract travel route and transportation costs to the platform server 10.

In step S43, the transmission unit 25 of the user terminal 20 transmits the abstract route data to the platform server 10. In the platform server 10, the registration unit 13 receives the abstract route data.

In step S44, the registration unit 13 registers the abstract route data in the abstract route database 32. The registration unit 13 generates a new route ID, associates the route ID with the abstract route data, and then stores the abstract route data in the abstract route database 32. The registered abstract route data can be used by various businesses or other users for various purposes.

In process flow S4, the user terminal 20 transmits abstract route data to the platform server 10 without transmitting original route data. Therefore, the platform server 10 does not acquire the original route data, and the database group 30 does not store the original route data. As a result, the original route data is not referenced on the server side. The server side is provided with abstract route data instead of the original route data, and the original route data does not leave the user terminal 20, so the user's travel route is appropriately anonymized. In addition, the user terminal 20 transmits information on the calculated transportation costs to the platform server 10. Therefore, the platform server 10 can accurately grasp the transportation costs to be charged to the user, and can, for example, settle the transportation costs on behalf of the transportation company. The user terminal 20 may confirm the user's clear intention when transmitting abstract route data or transportation cost information to the platform server 10.

[program]
The program for making the computer 110 function as the platform server 10 includes program codes for making the computer 110 function as the search unit 11, the map management unit 12, and the registration unit 13. The program for making the computer 110 function as the user terminal 20 includes program codes for making the computer 110 function as the route acquisition unit 21, the map storage area 22, the map update unit 23, the abstraction unit 24, and the transmission unit 25. Each program may be provided after being recorded in a fixed manner on a non-transitory recording medium such as a CD-ROM, a DVD-ROM, or a semiconductor memory. Alternatively, each program may be provided via a communication network as a data signal superimposed on a carrier wave. The provided program is stored in the storage 103. The processor 101 executes the program in cooperation with the memory 102, thereby realizing the corresponding functional module.

[effect]
As described above, a computer system according to an aspect of the present disclosure includes a processor. The processor generates abstract route data by abstracting original route data indicating a route of travel of a user, based on map data indicating a combination of map elements and an abstraction flag indicating whether to abstract route data.

The data structure of map data according to one aspect of the present disclosure represents a combination of map elements and an abstraction flag indicating whether or not to abstract route data.

A program according to one aspect of the present disclosure causes a computer to execute a step of abstracting original route data indicating a user's travel route to generate abstract route data, based on map data indicating a combination of map elements and an abstraction flag indicating whether or not to abstract the route data.

In this aspect, the original route data is abstracted based on the abstraction flags of the map elements, so that the user's travel route can be appropriately anonymized.

In another aspect of the computer system, the map elements may include links and nodes. The processor may set an abstraction flag corresponding to the link or node based on the number of homes and/or households associated with the link or node. In this manner, the abstraction flag can be set according to the number of residents in the vicinity of the link or node.

In a computer system according to another aspect, the map elements may include links and nodes. The processor may set an abstraction flag corresponding to the link or node based on an association between the link or node and a facility that is intended for use by an unspecified number of people. Whether a facility will be used by an unspecified number of people is related to whether an individual can be identified. By setting the abstraction flag in consideration of this association, the user's travel route can be appropriately anonymized.

In a computer system according to another aspect, the map elements may include links and nodes. The processor may set an abstraction flag corresponding to the link or node based on the number of people passing through the link or node. This mechanism allows the abstraction flag to be set according to the actual traffic situation of the link.

In a computer system according to another aspect, the map element may include a polygon node including a first small area and a second small area. The map data may indicate that the first small area is to be abstracted and that the second small area is not to be abstracted. When the travel route includes the first small area, the processor may convert the first small area into either the second small area or a polygon node to abstract the original route data. This mechanism allows the user's travel route in a two-dimensional geographical area to be appropriately anonymized.

[Modification]
The present disclosure has been described in detail above based on the embodiments. However, the present disclosure is not limited to the above embodiments. The present disclosure can be modified in various ways without departing from the spirit and scope of the present disclosure.

In the above embodiment, the abstraction flag for one map element has a value of either "1" (indicating abstraction) or "0" (indicating no abstraction), but this abstraction flag may be set for each time factor, such as date, time, or season. In other words, the abstraction flag may be ambiguous. For example, the abstraction flag for a map element may be set to "0" during the day and "1" at night. By setting the abstraction flag in this way, the need for abstraction can be set in more detail.

In the above embodiment, the user terminal 20 transmits the abstract route data to the platform server 10 in order to have the platform server 10 register the abstract route data in the abstract route database 32. However, the purpose of transmitting the abstract route data to the server is not limited to this. The terminal may also transmit the abstract route data to the server in order to have the server execute other processing.

In the above embodiment, a group of databases 30 is shown, but copies of each database may be placed at the platform provider and each of the multiple businesses. In this case, database synchronization is performed between the platform provider and the multiple businesses, thereby ensuring the consistency of various data. Blockchain technology or distributed ledger technology may be applied to the system that stores abstract route data.

For purposes of this disclosure, a first computer transmitting data or information "to" a second computer means that the first computer transmits data or information to the second computer either directly or through at least one communications device (i.e., indirectly).

In this disclosure, the expression "at least one processor executes a first process, executes a second process, ... executes an nth process" or a corresponding expression indicates a concept including cases where the entity executing the n processes from the first process to the nth process (i.e., the processor) changes midway. In other words, this expression indicates a concept including both cases where all n processes are executed by the same processor and cases where the processor changes among the n processes according to an arbitrary policy.

When comparing the magnitude of two numbers within a computer system, either of the two criteria "greater than or equal to" and "greater than" may be used, or either of the two criteria "less than or equal to" and "less than". The choice of criteria does not change the technical significance of the process of comparing the magnitude of two numbers.

The processing procedure of the method executed by at least one processor is not limited to the example in the above embodiment. For example, some of the steps (processing) described above may be omitted, or each step may be executed in a different order. In addition, any two or more of the steps described above may be combined, or some of the steps may be modified or deleted. Alternatively, other steps may be executed in addition to each of the steps described above.

The aspects described in all or part of the above embodiments solve any one of the following problems: control over movement paths, improving processing speed, improving processing accuracy, improving ease of use, improving functions using data or providing appropriate functions, other improving functions or providing appropriate functions, reducing the capacity of data and/or programs, miniaturizing devices and/or systems, providing appropriate data, programs, recording media, devices and/or systems, and optimizing the production and manufacturing of data, programs, recording media, devices and/or systems, such as reducing the production and manufacturing costs of data, programs, devices or systems, facilitating production and manufacturing, and shortening production and manufacturing times.

1... Information management system, 10... Platform server, 11... Search unit, 12... Map management unit, 13... Registration unit, 20... User terminal, 21... Route acquisition unit, 22... Map storage area, 23... Map update unit, 24... Abstraction unit, 25... Transmission unit, 28... Route search function, 29... Route tracing function, 30... Database group, 31... Map database, 32... Abstract route database, 40... Business operator server, 50... External system, 150... Map network , 151...node, 152...link, 153...polygon node, 153a...small area, 153b...small area, 153c...small area, 200...map data, 201...node data, 202...link data, 203...polygon node data, 204...POI data, 210...map data, 211...transportation node table, 212...transportation facility table, 213...transfer table, 401-406...roads, 411-422...links.

Claims (7)

A processor is provided.
The processor,
an abstraction flag included in map data indicating a combination of a map element and an abstraction flag indicating whether or not route data is abstracted so that a specific individual cannot be identified is set based on whether or not a predetermined condition indicating that an individual may be identified from the route data is satisfied;
generating abstract route data by abstracting original route data indicating a route traveled by the user based on the map data;
Computer system. A processor is provided.
The processor,
setting an abstraction flag corresponding to a link or a node, the abstraction flag being included in map data indicating a combination of map elements including links and nodes and an abstraction flag indicating whether route data is to be abstracted, based on the number of homes and/or households associated with the link or the node;
generating abstract route data by abstracting original route data indicating a route traveled by the user based on the map data;
Computer system. A processor is provided.
The processor,
setting an abstraction flag corresponding to a link or a node, the abstraction flag being included in map data indicating a combination of map elements including links and nodes and an abstraction flag indicating whether route data is to be abstracted, based on an association between the link or the node and a facility expected to be used by an unspecified number of people;
generating abstract route data by abstracting original route data indicating a route traveled by the user based on the map data;
Computer system. A processor is provided.
The processor,
setting an abstraction flag corresponding to a link or a node, the abstraction flag being included in map data indicating a combination of map elements including links and nodes and an abstraction flag indicating whether route data is to be abstracted, based on the number of people passing through the link or the node;
generating abstract route data by abstracting original route data indicating a route traveled by the user based on the map data;
Computer system. a processor for generating abstract route data by abstracting original route data indicating a route traveled by a user based on map data indicating a combination of map elements and an abstraction flag indicating whether or not to abstract route data;
the map element includes a polygon node including a first sub-region and a second sub-region;
the map data indicates that the first small area is to be abstracted and indicates that the second small area is not to be abstracted;
the processor, when the movement path includes the first small region, converts the first small region into either the second small region or the polygon node, thereby abstracting the original path data;
Computer system. setting an abstraction flag included in map data indicating a combination of a map element and an abstraction flag indicating whether or not route data is abstracted so that a specific individual cannot be identified, based on whether or not a predetermined condition indicating that an individual may be identified from the route data is satisfied;
generating abstract route data by abstracting original route data indicating a route traveled by a user based on the map data;
to cause a computer to execute
program. A step in which a computer sets an abstraction flag included in map data indicating a combination of a map element and an abstraction flag indicating whether or not route data is abstracted so that a specific individual cannot be identified, based on whether or not a predetermined condition indicating that an individual may be identified from the route data is satisfied;
A step in which a computer generates abstract route data by abstracting original route data indicating a route traveled by a user based on the map data;
Including,
method.

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