Adaptive spatial density based clustering

[0001] This application claims the benefit of priority of U.S. Patent Application Ser. No. 62/798,678, filed on Jan. 30, 2019, which is hereby incorporated by reference herein in its entirety

[0002] The popularity of location sharing, particularly real-time location sharing, used in conjunction with a social networking application continues to grow. Users increasingly share their location with each other, providing challenges to social networking systems seeking to help their members share their location. Embodiments of the present disclosure address these and other issues.

[0016] The description that follows includes systems, methods, techniques, instruction sequences, and computing machine program products that embody illustrative embodiments of the disclosure. In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide an understanding of various embodiments of the inventive subject matter. It will be evident, however, to those skilled in the art, that embodiments of the inventive subject matter may be practiced without these specific details. In general, well-known instruction instances, protocols, structures, and techniques are not necessarily shown in detail.

[0017] Embodiments of the present disclosure provide a geographically-based graphical user interface (GUI). This user interface may be referred to herein as a “map GUI,” and may be used in conjunction with a social media application. In some embodiments, the map GUI may include representations of at least approximate respective positions of a user and a user's friends in a social network graph accessed by the social media application using avatars for each respective user. In some embodiments, the map GUI also includes representations of at least approximate respective positions of a user's habitual places, such as his home, place of work or school.

[0018] Embodiments of the present disclosure provide systems, methods, techniques, instruction sequences, and computing machine program products for identifying habitual places of a user, the habitual places of a user being the places where the user spends most of his/her time. In some embodiments, historical location information of a user is accessed, and a plurality of visit points are identified based on the historical location information. A visit point may be defined as a location where the user stays within a maximum range for a minimum amount of time. The plurality of visit points is clustered into a plurality of clusters using a density-based clustering algorithm. Each one of the clusters is then identified as a habitual place of the user.

[0019] Conventional density-based clustering algorithm, such as DBSCAN, require selecting a density threshold once and for all, and the density threshold cannot evolve over time or space. As a result, as the number of visit points to be clustered increase over time, and due to the inherent positioning inaccuracy of any positioning system, clusters of visit points tend to merge into huge spread clusters that do not allow identification of the user's habitual places.

[0020] Motivated by these challenges, some embodiments of the present disclosure provide improvements over methods based on conventional density-based clustering algorithms by dynamically adjusting the density threshold of the clustering algorithm. For example, in some embodiments, when the number of visit points in one of the clusters exceeds a maximum cluster size, the clustering is repeated with an increased density threshold.

[0021] Embodiments of the present disclosure are described in relation to clustering visit points. However, the clustering methods described in the present disclosure may be used to cluster other types of location data. For example, the clustering methods described in the present disclosure may be used to cluster location data of a plurality of users to identify popular routes or popular places.

[0022] In some embodiments, when the server receives, from a client device associated with the user, via a wireless communication, an electronic communication containing current location information of the user, the server identifies a current location of the user based on the current location information, and, if the current location of the user is in a neighborhood of one of the clusters, determine that the user is at the habitual place associated with the cluster.

[0023] FIG. 1 is a block diagram showing an example location sharing system 100 for exchanging location data over a network. The location sharing system 100 includes multiple instances of a client device 102, each of which hosts a number of applications including a location sharing client application 104. Each location sharing client application 104 is communicatively coupled to other instances of the location sharing client application 104 and a location sharing server system 108 via a network 106 (e.g., the Internet).

[0024] A location sharing client application 104 is able to communicate and exchange data with another location sharing client application 104 and with the location sharing server system 108 via the network 106. The data exchanged between location sharing client application 104, and between a location sharing client application 104 and the location sharing server system 108, includes functions (e.g., commands to invoke functions) as well as payload data (e.g., location data, text, audio, video or other multimedia data).

[0025] The location sharing server system 108 provides server-side functionality via the network 106 to a particular location sharing client application 104. While certain functions of the location sharing system 100 are described herein as being performed by either a location sharing client application 104 or by the location sharing server system 108, the location of certain functionality either within the location sharing client application 104 or the location sharing server system 108 is a design choice. For example, it may be technically preferable to initially deploy certain technology and functionality within the location sharing server system 108, but to later migrate this technology and functionality to the location sharing client application 104 where a client device 102 has a sufficient processing capacity.

[0026] The location sharing server system 108 supports various services and operations that are provided to the location sharing client application 104. Such operations include transmitting data to, receiving data from, and processing data generated by the location sharing client application 104. This data may include, geolocation information, message content, client device information, media annotation and overlays, message content persistence conditions, social network information, and live event information, as examples. Data exchanges within the location sharing system 100 are invoked and controlled through functions available via user interfaces (UIs) of the location sharing client application 104.

[0027] Turning now specifically to the location sharing server system 108, an Application Program Interface (API) server 110 is coupled to, and provides a programmatic interface to, an application server 112. The application server 112 is communicatively coupled to a database server 118, which facilitates access to a database 120 in which is stored data associated with messages processed by the application server 112.

[0028] The Application Program Interface (API) server 110 receives and transmits message data (e.g., commands and message payloads) between the client device 102 and the application server 112. Specifically, the Application Program Interface (API) server 110 provides a set of interfaces (e.g., routines and protocols) that can be called or queried by the location sharing client application 104 in order to invoke functionality of the application server 112. The Application Program Interface (API) server 110 exposes various functions supported by the application server 112, including account registration, login functionality, the sending of messages, via the application server 112, from a particular location sharing client application 104 to another location sharing client application 104, the sending of media files (e.g., images or video) from a location sharing client application 104 to the location sharing server application 114, and for possible access by another location sharing client application 104, the setting of a collection of media data (e.g., story), the retrieval of a list of friends of a user of a client device 102, the retrieval of such collections, the retrieval of messages and content, the adding and deletion of friends to a social graph, the location of friends within a social graph, and opening an application event (e.g., relating to the location sharing client application 104).

[0029] The application server 112 hosts a number of applications and subsystems, including a location sharing server application 114, a messaging system 116 and a social network system 122.

[0030] Examples of functions and services supported by the location sharing server application 114 include generating a map GUI. In some embodiments, the map GUI may include representations of at least approximate respective positions of a user and a user's friends in a social network graph accessed by the social media application using avatars for each respective user.

[0031] The location sharing server application 114 may receive user authorization to use, or refrain from using, the user's location information. In some embodiments, the location sharing server application 114 may likewise opt to share or not share the user's location with others via the map GUI. In some cases, the user's avatar may be displayed to the user on the display screen of the user's computing device regardless of whether the user is sharing his or her location with other users.

[0032] In some embodiments, a user can select groups of other users to which his/her location will be displayed, and may in specify different display attributes for the different respective groups or for different respective individuals. In one example, audience options include: “Best Friends,” “Friends,” and “Custom” (which is an individual-level whitelist of people). In this example, if “Friends” are selected, all new people added to the user's friends list will automatically be able to see their location. If they are already sharing with the user, their avatars will appear on the user's map.

[0033] In some embodiments, when viewing the map GUI, the user is able to see the location of all his/her friends that have shared their location with the user on the map, each friend represented by their respective avatar. In some embodiments, if the friend does not have an avatar, the friend may be represented using a profile picture or a default icon displayed at the corresponding location for the friend.

[0034] In some embodiments, the user can select between friends on the map via a menu, such as a carousel. In some embodiments, selecting a particular friend automatically centers the map view on the avatar of that friend. Embodiments of the present disclosure may also allow the user to take a variety of actions with the user's friends from within the map GUI. For example, the system may allow the user to chat with the user's friends without leaving the map. In one particular example, the user may select a chat icon from a menu presented in conjunction with the map GUI to initiate a chat session.

[0035] The messaging system 116 implements a number of message processing technologies and functions, particularly related to the aggregation and other processing of content (e.g., textual and multimedia content) included in messages received from multiple instances of the location sharing client application 104. As will be described in further detail, the text and media content from multiple sources may be aggregated into collections of content (e.g., called stories or galleries). These collections are then made available, by the location sharing server application 114, to the location sharing client application 104. Other processor and memory intensive processing of data may also be performed server-side by the location sharing server application 114, in view of the hardware requirements for such processing.

[0036] The application server 112 is communicatively coupled to a database server 118, which facilitates access to a database 120 in which is stored data processed by the location sharing server application 114.

[0037] The social network system 122 supports various social networking functions services, and makes these functions and services available to the location sharing server application 114. To this end, the social network system 122 maintains and accesses an entity graph 204 (as shown in FIG. 2) within the database 120. Examples of functions and services supported by the social network system 122 include the identification of other users of the location sharing system 100 with which a particular user has relationships or is “following”, and also the identification of other entities and interests of a particular user.

[0038] FIG. 2 is a schematic diagram illustrating data structures 200 which may be stored in the database 120 of the location sharing server system 108, according to certain example embodiments. While the content of the database 120 is shown to comprise a number of tables, it will be appreciated that the data could be stored in other types of data structures (e.g., as an object-oriented database).

[0039] The database 120 includes message data stored within a message table 208. An entity table 202 stores entity data, including an entity graph 204. Entities for which records are maintained within the entity table 202 may include individuals (e.g., users), corporate entities, organizations, objects, places, events, etc. Regardless of type, any entity regarding which the location sharing server system 108 stores data may be a recognized entity. Each entity is provided with a unique identifier, as well as an entity type identifier (not shown). The entity graph 204 furthermore stores information regarding relationships and associations between entities. Such relationships may be social, professional (e.g., work at a common corporation or organization) interested-based or activity-based, merely for example. A location table 206 stores location information of users (e.g., geolocation information determined by the position components 538 of the client device 102). Location information may include a plurality of location points defined by at least a set of geographical coordinates and a time stamp.

[0040] Turning now to FIG. 3, there is shown a diagrammatic representation of a processing environment 300, which includes at least a processor 302 (e.g., a GPU, CPU or combination thereof).

[0041] The processor 302 is shown to be coupled to a power source 304, and to include (either permanently configured or temporarily instantiated) modules, namely a location component 308, a historical location component 314, a clustering component 312, and a map GUI component 310. The location component 308 operationally determines instant location of users based on instant location information collected by one or more client devices (e.g., client device 102) associated with the user. The historical location component 308 generates historical location information of a user by consolidating instant location information collected over time by one or more client devices (e.g., client device 102) associated with the user. The clustering component 312 operationally generates information related to habitual places of users. The map GUI component 310 operationally generates user interfaces and causes the user interfaces to be displayed on client devices. As illustrated, the processor 302 may be communicatively coupled to another processor 306.

[0042] FIG. 4 is a block diagram 400 illustrating a software architecture 404, which can be installed on any one or more of the devices described herein. The software architecture 404 is supported by hardware such as a machine 402 that includes processors 420, memory 426, and I/O components 438. In this example, the software architecture 404 can be conceptualized as a stack of layers, where each layer provides a particular functionality. The software architecture 404 includes layers such as an operating system 412, libraries 410, frameworks 408, and applications 406. Operationally, the applications 406 invoke API calls 450 through the software stack and receive messages 452 in response to the API calls 450.

[0043] The operating system 412 manages hardware resources and provides common services. The operating system 412 includes, for example, a kernel 414, services 416, and drivers 422. The kernel 414 acts as an abstraction layer between the hardware and the other software layers. For example, the kernel 414 provides memory management, processor management (e.g., scheduling), component management, networking, and security settings, among other functionality. The services 416 can provide other common services for the other software layers. The drivers 422 are responsible for controlling or interfacing with the underlying hardware. For instance, the drivers 422 can include display drivers, camera drivers, BLUETOOTH® or BLUETOOTH® Low Energy drivers, flash memory drivers, serial communication drivers (e.g., Universal Serial Bus (USB) drivers), WI-FI® drivers, audio drivers, power management drivers, and so forth.

[0044] The libraries 410 provide a low-level common infrastructure used by the applications 406. The libraries 410 can include system libraries 418 (e.g., C standard library) that provide functions such as memory allocation functions, string manipulation functions, mathematic functions, and the like. In addition, the libraries 410 can include API libraries 424 such as media libraries (e.g., libraries to support presentation and manipulation of various media formats such as Moving Picture Experts Group-4 (MPEG4), Advanced Video Coding (H.264 or AVC), Moving Picture Experts Group Layer-3 (MP3). Advanced Audio Coding (AAC). Adaptive Multi-Rate (AMR) audio codec. Joint Photographic Experts Group (JPEG or JPG), or Portable Network Graphics (PNG)), graphics libraries (e.g., an OpenGL framework used to render in two dimensions (2D) and three dimensions (3D) in a graphic content on a display), database libraries (e.g., SQLite to provide various relational database functions), web libraries (e.g., WebKit to provide web browsing functionality), and the like. The libraries 410 can also include a wide variety of other libraries 428 to provide many other APIs to the applications 406.

[0045] The frameworks 408 provide a high-level common infrastructure that is used by the applications 406. For example, the frameworks 408 provide various graphical user interface (GUI) functions, high-level resource management, and high-level location services. The frameworks 408 can provide a broad spectrum of other APIs that can be used by the applications 406, some of which may be specific to a particular operating system or platform.

[0046] In an example embodiment, the applications 406 may include a home application 436, a contacts application 430, a browser application 432, a book reader application 434, a location application 442, a media application 444, a messaging application 446, a game application 448, and a broad assortment of other applications such as third-party applications 440. The applications 406 are programs that execute functions defined in the programs. Various programming languages can be employed to create one or more of the applications 406, structured in a variety of manners, such as object-oriented programming languages (e.g., Objective-C. Java. or C++) or procedural programming languages (e.g., C or assembly language). In a specific example, the third-party applications 440 (e.g., applications developed using the ANDROID™ or IOS™ software development kit (SDK) by an entity other than the vendor of the particular platform) may be mobile software running on a mobile operating system such as IOS™, ANDROID™, WINDOWS® Phone, or another mobile operating system. In this example, the third-party applications 440 can invoke the API calls 450 provided by the operating system 412 to facilitate functionality described herein.

[0047] FIG. 5 is a diagrammatic representation of a machine 500 within which instructions 508 (e.g., software, a program, an application, an applet, an app, or other executable code) for causing the machine 500 to perform any one or more of the methodologies discussed herein may be executed. For example, the instructions 508 may cause the machine 500 to execute any one or more of the methods described herein. The instructions 508 transform the general, non-programmed machine 500 into a particular machine 500 programmed to carry out the described and illustrated functions in the manner described. The machine 500 may operate as a standalone device or may be coupled (e.g., networked) to other machines. In a networked deployment, the machine 500 may operate in the capacity of a server machine or a client machine in a server-client network environment, or as a peer machine in a peer-to-peer (or distributed) network environment. The machine 500 may comprise, but not be limited to, a server computer, a client computer, a personal computer (PC), a tablet computer, a laptop computer, a netbook, a set-top box (STB), a PDA, an entertainment media system, a cellular telephone, a smart phone, a mobile device, a wearable device (e.g., a smart watch), a smart home device (e.g., a smart appliance), other smart devices, a web appliance, a network router, a network switch, a network bridge, or any machine capable of executing the instructions 508, sequentially or otherwise, that specify actions to be taken by the machine 500. Further, while only a single machine 500 is illustrated, the term “machine” shall also be taken to include a collection of machines that individually or jointly execute the instructions 508 to perform any one or more of the methodologies discussed herein.

[0048] The machine 500 may include processors 502, memory 504, and I/O components 542, which may be configured to communicate with each other via a bus 544. In an example embodiment, the processors 502 (e.g., a Central Processing Unit (CPU), a Reduced Instruction Set Computing (RISC) processor, a Complex Instruction Set Computing (CISC) processor, a Graphics Processing Unit (GPU), a Digital Signal Processor (DSP), an ASIC, a Radio-Frequency Integrated Circuit (RFIC), another processor, or any suitable combination thereof) may include, for example, a processor 506 and a processor 510 that execute the instructions 508. The term “processor” is intended to include multi-core processors that may comprise two or more independent processors (sometimes referred to as “cores”) that may execute instructions contemporaneously. Although FIG. 5 shows multiple processors 502, the machine 500 may include a single processor with a single core, a single processor with multiple cores (e.g., a multi-core processor), multiple processors with a single core, multiple processors with multiples cores, or any combination thereof.

[0049] The memory 504 includes a main memory 512, a static memory 514, and a storage unit 516, both accessible to the processors 502 via the bus 544. The main memory 504, the static memory 514, and storage unit 516 store the instructions 508 embodying any one or more of the methodologies or functions described herein. The instructions 508 may also reside, completely or partially, within the main memory 512, within the static memory 514, within machine-readable medium 518 within the storage unit 516, within at least one of the processors 502 (e.g., within the processor's cache memory), or any suitable combination thereof, during execution thereof by the machine 500.

[0050] The I/O components 542 may include a wide variety of components to receive input, provide output, produce output, transmit information, exchange information, capture measurements, and so on. The specific I/O components 542 that are included in a particular machine will depend on the type of machine. For example, portable machines such as mobile phones may include a touch input device or other such input mechanisms, while a headless server machine will likely not include such a touch input device. It will be appreciated that the I/O components 542 may include many other components that are not shown in FIG. 5. In various example embodiments, the I/O components 542 may include output components 528 and input components 530. The output components 528 may include visual components (e.g., a display such as a plasma display panel (PDP), a light emitting diode (LED) display, a liquid crystal display (LCD), a projector, or a cathode ray tube (CRT)), acoustic components (e.g., speakers), haptic components (e.g., a vibratory motor, resistance mechanisms), other signal generators, and so forth. The input components 530 may include alphanumeric input components (e.g., a keyboard, a touch screen configured to receive alphanumeric input, a photo-optical keyboard, or other alphanumeric input components), point-based input components (e.g., a mouse, a touchpad, a trackball, a joystick, a motion sensor, or another pointing instrument), tactile input components (e.g., a physical button, a touch screen that provides location and/or force of touches or touch gestures, or other tactile input components), audio input components (e.g., a microphone), and the like.

[0051] In further example embodiments, the I/O components 542 may include biometric components 532, motion components 534, environmental components 536, or position components 538, among a wide array of other components. For example, the biometric components 532 include components to detect expressions (e.g., hand expressions, facial expressions, vocal expressions, body gestures, or eye tracking), measure biosignals (e.g., blood pressure, heart rate, body temperature, perspiration, or brain waves), identify a person (e.g., voice identification, retinal identification, facial identification, fingerprint identification, or electroencephalogram-based identification), and the like. The motion components 534 include acceleration sensor components (e.g., accelerometer), gravitation sensor components, rotation sensor components (e.g., gyroscope), and so forth. The environmental components 536 include, for example, illumination sensor components (e.g., photometer), temperature sensor components (e.g., one or more thermometers that detect ambient temperature), humidity sensor components, pressure sensor components (e.g., barometer), acoustic sensor components (e.g., one or more microphones that detect background noise), proximity sensor components (e.g., infrared sensors that detect nearby objects), gas sensors (e.g., gas detection sensors to detection concentrations of hazardous gases for safety or to measure pollutants in the atmosphere), or other components that may provide indications, measurements, or signals corresponding to a surrounding physical environment. The position components 538 include location sensor components (e.g., a GPS receiver component), altitude sensor components (e.g., altimeters or barometers that detect air pressure from which altitude may be derived), orientation sensor components (e.g., magnetometers), and the like.

[0052] Communication may be implemented using a wide variety of technologies. The I/O components 542 further include communication components 540 operable to couple the machine 500 to a network 520 or devices 522 via a coupling 524 and a coupling 526, respectively. For example, the communication components 540 may include a network interface component or another suitable device to interface with the network 520. In further examples, the communication components 540 may include wired communication components, wireless communication components, cellular communication components. Near Field Communication (NFC) components, Bluetooth® components (e.g., Bluetooth® Low Energy), Wi-Fi® components, and other communication components to provide communication via other modalities. The devices 522 may be another machine or any of a wide variety of peripheral devices (e.g., a peripheral device coupled via a USB).

[0053] Moreover, the communication components 540 may detect identifiers or include components operable to detect identifiers. For example, the communication components 540 may include Radio Frequency Identification (RFID) tag reader components, NFC smart tag detection components, optical reader components (e.g., an optical sensor to detect one-dimensional bar codes such as Universal Product Code (UPC) bar code, multi-dimensional bar codes such as Quick Response (QR) code. Aztec code, Data Matrix, Dataglyph, MaxiCode. PDF417, Ultra Code, UCC RSS-2D bar code, and other optical codes), or acoustic detection components (e.g., microphones to identify tagged audio signals). In addition, a variety of information may be derived via the communication components 540, such as location via Internet Protocol (IP) geolocation, location via Wi-Fi® signal triangulation, location via detecting an NFC beacon signal that may indicate a particular location, and so forth.

[0054] The various memories (e.g., memory 504, main memory 512, static memory 514, and/or memory of the processors 502) and/or storage unit 516 may store one or more sets of instructions and data structures (e.g., software) embodying or used by any one or more of the methodologies or functions described herein. These instructions (e.g., the instructions 508), when executed by processors 502, cause various operations to implement the disclosed embodiments.

[0055] The instructions 508 may be transmitted or received over the network 520, using a transmission medium, via a network interface device (e.g., a network interface component included in the communication components 540) and using any one of a number of well-known transfer protocols (e.g., hypertext transfer protocol (HTTP)). Similarly, the instructions 508 may be transmitted or received using a transmission medium via the coupling 526 (e.g., a peer-to-peer coupling) to the devices 522.

[0056] FIG. 6 is a flowchart illustrating a method 600 for identifying the habitual places of a user, the habitual places of a user being the places where the user spends most of his/her time. The method 600 may be embodied in computer-readable instructions for execution by one or more processors (e.g., processor 302) such that the steps of the method 600 may be performed in part or in whole by functional components (e.g., location component 308, historical location component 314, clustering component 312, map GUI component 310) of a processing environment 300 of a system (e.g., location sharing server system 108); accordingly, the method 600 is described below by way of example with reference thereto. However, method 600 may be deployed on various other hardware configurations and is not intended to be limited to the functional components of the processing environment 300. Method 600 may be performed periodically or when a number of visit points identified for a user reaches one or more preset thresholds.

[0057] In block 602, the system accesses historical location information of the user. The historical location information of a user may be generated by consolidating instant location information collected over time by one or more client devices (e.g., client device 102) associated with the user. The historical location information includes a plurality of location points (e.g., GPS points), each point being defined by at least a set of geographical coordinates and a time stamp. In some embodiments, the system may need to receive authorization from the user to utilize location information from the user's client devices prior to performing the remaining steps of method 600. Such authorization may be obtained via acceptance of a terms of service for utilizing an online social network or other service provided by the system, by acceptance on a case-by-case basis by the first user (e.g., via popups displayed on the user's computing device) or using any other suitable method for obtaining authorization by the user(s).

[0058] In block 604, the system identifies a plurality of visit points based on the historical location information. A visit point may be defined as a location where the user stays within a maximum range for a minimum amount of time. A visit point is defined by at least a set of geographical coordinates, a start timestamp, and an end timestamp. The visit points may be identified by spatio-temporal clustering of the plurality of location points based on time and distance proximity, and selecting within the cluster only points having geographical coordinates located within a range that is smaller than a preset maximum range depending on a variable precision, and time stamps spanning over a period of time that is longer than a preset minimum amount of time.

[0059] In block 606, the system clusters the plurality of visit points into a plurality of clusters, the clustering being performed based on a density threshold. The density threshold may be initially set at a preset value, for example 2. Examples of clustering algorithms that may be implemented to cluster the plurality of visit points are described in relation to FIG. 8.

[0060] At decision block 608, the system determines whether the number of visit points in any one of the clusters exceeds a maximum cluster size (e.g., a maximum number of visit points in a cluster). The maximum cluster size is a preset number. The maximum cluster size may be a multiple of the density threshold. If, at least one of the clusters includes a number of visit points that exceeds the maximum cluster size, the system increases, in block 614, the density threshold, and repeats the clustering (e.g., block 606) with an increased density threshold. If none of the clusters includes a number of visit points exceeding the maximum cluster size, the system continues to block 610.

[0061] In block 610, the system identifies some or each one of the clusters as a habitual place of the user.

[0062] In block 612, the system may associate some or each habitual place of the user with a category (e.g., domicile, work place, or school) based on an analysis of the visit points included in the cluster associated with the habitual place. In particular, a category (e.g., domicile, work place, or school) of the habitual place may be determined by analyzing the timestamps of the visit points included in the cluster. For example, the cluster including the highest number of visit points associated with a timestamp corresponding to nighttime may be associated with the specific habitual place “domicile”.

[0063] FIG. 7 is a flowchart illustrating a method 700 for generating and presenting various user interfaces to share location information concerning the location of a first user with a second user. The method 700 may be embodied in computer-readable instructions for execution by one or more processors (e.g., processor 302) such that the steps of the method 700 may be performed in part or in whole by functional components (e.g., location component 308, clustering component 312, and map GUI component 310) of a processing environment 300 of a system (e.g., location sharing server system 108); accordingly, the method 700 is described below by way of example with reference thereto. However, method 700 may be deployed on various other hardware configurations and is not intended to be limited to the functional components of the processing environment 300. Method 700 may be performed after method 600.

[0064] In block 702, the system receives, from a client device (e.g., client device 102) associated with a first user, via a wireless communication, over a network (e.g., network 106), an electronic communication containing current location information of the first user.

[0065] The current location information may be generated by one or more location sensors (e.g., position components 538) coupled to the client device. In some embodiments, the location sensors may include a global positioning sensor (GPS) component integrated in the client device, as well as other types of location sensors.

[0066] The system may receive location information on a periodic basis or on an irregular basis and may request information from the client device or receive such information from the client device without such a request. In some embodiments, the client device contains software that monitors the location sensor information from the client device and transmits updates to the system in response to the location changing. In some cases, the client device may update the system with a new location only after the location changes by at least a predetermined distance to allow a user to move about a building or other location without triggering updates.

[0067] In block 704, the system identifies a current location of the first user based on the current location information. The system analyzes the received location information and determines a current location of the user. The system may use any number of different location measurements to determine the user's current location. In some embodiments, for example, the system may determine a speed of the client device (e.g., in real-time or near-real-time) based on first location information from the location sensor on the client device at a first time, and second location information from the location sensor at a second (subsequent) time. The speed and location information can be analyzed together to help determine the current location of the user.

[0068] In block 706, based on determining that the current location of the first user is in a neighborhood of one of the clusters, the system determines that the first user is at the particular habitual place associated with the cluster. In some embodiments, the current location of the first user may be considered to be in a neighborhood of a cluster if it is within a preset distance of the center of the cluster. The distance may be computed with any distance function. In some embodiments, each habitual place is defined by a bounding box including all the visit points included in the cluster associate with the habitual place. The system determines the current location of the first user as a two-dimensional Gaussian probability distribution (e.g., the two dimensions being the latitude and the longitude) centered around the geographical coordinates of the location point provided by the positioning system (e.g., GPS), the standard deviation along both dimensions being defined by the precision of the positioning system along respectively latitude and longitude. The system computes a probability of the first user being at the habitual place based on a joint probability of the latitude and the longitude of the current location of the first user being included in the bounding box. The probability of the latitude of the current location of the first user being included in the bounding box may be computed as the area under the section of the Gaussian probability distribution along the latitude axis that intersects the bounding box. Similarly, the probability of the longitude of the current location of the first user being included in the bounding box may be computed as the area under the section of the Gaussian probability distribution along the longitude axis that intersects the bounding box. The joint probability of the latitude and the longitude being included in the bounding box is computed based on the probability of the latitude being included in the bounding box, and the probability of the longitude being included in the bounding box, the probability of the latitude being included in the bounding box, and the probability of the longitude being included in the bounding box being considered independent. If the probability of the first user being at the habitual place exceeds a threshold, the system determines that the first user is at the particular habitual place.

[0069] In block 708, the system may cause display, on a display screen of a client device of the first user, of a user interface (e.g., user interface 1300 of FIG. 13) including a map depicting an icon of the particular habitual place associated with the cluster. The location of an icon on the map is representative of the location of the associated habitual place.

[0070] In block 710, the system may cause display, on a display screen of a client device of a second user, of a user interface (e.g., user interface 1400 of FIG. 14) including a map depicting an icon associated with the particular habitual place associated with the cluster alongside the avatar of the first user, to notify the second user that the first user is at his/her habitual place.

[0071] FIG. 8 is a flowchart illustrating a routine 800 for clustering points based on a density-based clustering algorithm (e.g., DBSCAN). The routine 800 may be embodied in computer-readable instructions for execution by one or more processors (e.g., processor 302) such that the steps of the routine 1000 may be performed in part or in whole by functional components (e.g., clustering component 312) of a processing environment 300 of a system (e.g., location sharing server system 108); accordingly, the routine 800 is described below by way of example with reference thereto. However, routine 800 may be deployed on various other hardware configurations and is not intended to be limited to the functional components of the processing environment 300. Consistent with some embodiments, routine 800 may be performed as part of (e.g., as sub-operations or as a subroutine) of operation 606 of method 600 for clustering the plurality of visit points.

[0072] The density-based clustering algorithm requires two parameters: ε (cps) and minPts. ε is the maximum radius of a neighborhood. minPts is the density threshold (i.e., the minimum number of points required to form a dense region). The algorithm can be used with any distance function.

[0073] The points are classified as core points, non-core points and noise. A point p is a core point if at least minPts points (including p) are within distance E of p. The points that are within distance c of a core point but that are not core points are non-core points. The points that are not within distance c of any core point are noise points. A cluster includes all points (core or non-core) that are within distance E of a core point included in said cluster.

[0074] In block 824, routine 800 selects a starting point among the visit points that have not been visited yet. In block 802, routine 800 identifies the F-neighborhood of the starting point (the points that are within distance E of the starting point). In decision block 804, routine 800 determines whether the number of points included in the e-neighborhood of the starting point exceeds the density threshold. If the number of points included in the E-neighborhood of the starting point is below the density threshold, routine 800 labels, at block 806, the starting point as noise, and goes back to block 824, selecting another starting point among the unvisited points.

[0075] If the number of points included in the e-neighborhood of the starting point exceeds the density threshold, routine 800 labels, at block 808, the starting point as core point, and creates, at block 810 a cluster including the starting point and all the points included in the E-neighborhood of the starting point. In block 812, routine 800 selected one of the unvisited points included in the cluster, and identifies the e-neighborhood of the point (the points that are within distance c of the point). In decision block 814, routine 800 determines whether the c-neighborhood of the point includes a number of points that exceeds the density threshold. If the number of points included in the e-neighborhood of the point is below the density threshold, routine 800 labels, in block 828, the point as non-core point, and goes to decision block 822. If the number of points included in the c-neighborhood of the point exceeds the density threshold, routine 800 labels, in block 816, the point as core point, adds, in block 818, all the points included in the e-neighborhood of the point to the cluster, and goes to decision block 822.

[0076] In decision block 822, routine 800 determines whether all the points of the cluster have been visited. If some of the points of the cluster are unvisited, routine 800 goes back to block 812, selecting one of the unvisited points of the cluster. If all the points of the cluster have been visited, routine 800 goes to decision block 820, determining whether all the points have been visited. If some of the points are unvisited, routine 800 goes back to block 824, selecting one of the unvisited points as starting point. If all the points have been visited, routine 800 ends (end 826).

[0077] FIG. 9 illustrates the clustering of a set of visit points identified for a user at a first point in time. The visit points are clustered using on a density-based clustering algorithm (e.g., DBSCAN) (e.g., at block 606 of FIG. 6). The points are classified as core points 904 of a first cluster, non-core points 902 of the first cluster, core points 908 of a second cluster, non-core points 906 of the second cluster and noise points 910. Points that are in low-density regions (points with many close nearby neighbors) are grouped together. Points that lie alone in low-density regions (points whose nearest neighbors are too far away) are marked as noise points.

[0078] In the illustrative example of FIG. 10, two clusters are identified (e.g., at block 606 of FIG. 6). As shown on FIG. 10, one of the clusters of points is associated (e.g., at block 610 of FIG. 6) with a first habitual place 1002 of the user (e.g., the user's domicile), and the other cluster of points is associated with a second habitual place 1004 of the user (e.g., the user's work place).

[0079] FIG. 11 illustrates the clustering of a set of visit points identified for the user at a second point in time, the second point in time being subsequent to the first point in time. Additional instant location points have been collected between the first point in time and the second point in time. As a consequence, the number of visit points has grown between the first point in time and the second point in time. The clustering of the visit points identified for the user at the second point in time is initially performed (e.g., at block 606 of FIG. 6) based on the same density threshold as the one used for the clustering of the visit points identified for the user at the first point in time. However, this time, as illustrated on FIG. 10, only one single spread cluster can be identified. The points are classified as core points 1104 of a first cluster, non-core points 1102 of the first cluster, and noise points 1110. The spread cluster does not allow identification of the user's habitual places. However, the system determines (e.g., at decision block 608) that the number of visit points in the cluster exceeds a maximum cluster size, and repeats (e.g., at block 612 and block 606 of FIG. 6) the clustering based on an increased density threshold.

[0080] FIG. 12 illustrates the clustering of the set of visit points identified for the user at the second point in time clustered based on the increased density threshold. As a consequence of the increased density threshold, some points that were labeled as core points 1104 of a first cluster on FIG. 9 are now labeled as non-core points of the first cluster 1202 or noise points noise points 1210, and some points that were labeled as non-core points of the first cluster 1102 are now labeled as noise points 1210. As a consequence, two clusters can be distinguished. The points are classified as core points 1204 of a first cluster, non-core points 1202 of the first cluster, core points 1208 of a second cluster, non-core points 1206 of the second cluster and noise 1210.

[0081] FIG. 13 illustrates a user interface 1300 that may be displayed on a display screen of the user. User interface 1300 includes a map GUI 1304 depicting an icon 1302. The icon 1302 is a media content item associated with the habitual place of the user and that may include a still image, animated image, video, or other content. The icon 1302 of a habitual place may be based a category of the habitual place. For example, if the habitual place is identified as the domicile of the user, the icon 1302 may be an image depicting a house. The location of the icon 1302 on the map GUI 1304 is representative of the location of the habitual place.

[0082] FIG. 14 illustrates a user interface 1400 that may be displayed on a display screen of a second user. User interface 1400 includes a map GUI 1406 depicting an avatar 1402 of the first user. The avatar 1402 is a media content item associated with the first user and that may include a still image, animated image, video, or other content. The avatar may include a profile picture or a default icon. The location of the first user's avatar 1402 on the map GUI 1406 is representative of the current location of the first user. The system updates the location of the first user's avatar 1402 on the map GUI 1406 as the location of a client device of the first user changes. If the system detects that the first user is at one of his/her habitual place, the map GUI 1406 depicts an icon 1404 associated with the habitual place alongside the avatar 1402 of the first user. The icon 1404 is a media content item associated with the habitual place of the user and that may include a still image, animated image, video, or other content. The icon 1404 of a habitual place may be based a category of the habitual place. For example, if the habitual place is identified as the domicile of the user, the icon 1404 may be an image depicting a house.

[0083] Throughout this specification, plural instances may implement components, operations, or structures described as a single instance. Although individual operations of one or more methods are illustrated and described as separate operations, one or more of the individual operations may be performed concurrently, and nothing requires that the operations be performed in the order illustrated. Structures and functionality presented as separate components in example configurations may be implemented as a combined structure or component. Similarly, structures and functionality presented as a single component may be implemented as separate components. These and other variations, modifications, additions, and improvements fall within the scope of the subject matter herein.

[0084] Although an overview of the inventive subject matter has been described with reference to specific example embodiments, various modifications and changes may be made to these embodiments without departing from the broader scope of embodiments of the present disclosure.

[0085] The embodiments illustrated herein are described in sufficient detail to enable those skilled in the art to practice the teachings disclosed. Other embodiments may be used and derived therefrom, such that structural and logical substitutions and changes may be made without departing from the scope of this disclosure. The Detailed Description, therefore, is not to be taken in a limiting sense, and the scope of various embodiments is defined only by the appended claims, along with the full range of equivalents to which such claims are entitled.

[0086] As used herein, the term “or” may be construed in either an inclusive or exclusive sense. Moreover, plural instances may be provided for resources, operations, or structures described herein as a single instance. Additionally, boundaries between various resources, operations, modules, engines, and data stores are somewhat arbitrary, and particular operations are illustrated in a context of specific illustrative configurations. Other allocations of functionality are envisioned and may fall within a scope of various embodiments of the present disclosure. In general, structures and functionality presented as separate resources in the example configurations may be implemented as a combined structure or resource. Similarly, structures and functionality presented as a single resource may be implemented as separate resources. These and other variations, modifications, additions, and improvements fall within a scope of embodiments of the present disclosure as represented by the appended claims. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense.

[0087] “Signal Medium” refers to any intangible medium that is capable of storing, encoding, or carrying the instructions for execution by a machine and includes digital or analog communications signals or other intangible media to facilitate communication of software or data. The term “signal medium” shall be taken to include any form of a modulated data signal, carrier wave, and so forth. The term “modulated data signal” means a signal that has one or more of its characteristics set or changed in such a matter as to encode information in the signal. The terms “transmission medium” and “signal medium” mean the same thing and may be used interchangeably in this disclosure.

[0088] “Communication Network” refers to one or more portions of a network that may be an ad hoc network, an intranet, an extranet, a virtual private network (VPN), a local area network (LAN), a wireless LAN (WLAN), a wide area network (WAN), a wireless WAN (WWAN), a metropolitan area network (MAN), the Internet, a portion of the Internet, a portion of the Public Switched Telephone Network (PSTN), a plain old telephone service (POTS) network, a cellular telephone network, a wireless network, a Wi-Fi® network, another type of network, or a combination of two or more such networks. For example, a network or a portion of a network may include a wireless or cellular network and the coupling may be a Code Division Multiple Access (CDMA) connection, a Global System for Mobile communications (GSM) connection, or other types of cellular or wireless coupling. In this example, the coupling may implement any of a variety of types of data transfer technology, such as Single Carrier Radio Transmission Technology (1×RTT). Evolution-Data Optimized (EVDO) technology, General Packet Radio Service (GPRS) technology, Enhanced Data rates for GSM Evolution (EDGE) technology, third Generation Partnership Project (3GPP) including 3G, fourth generation wireless (4G) networks, Universal Mobile Telecommunications System (UMTS), High Speed Packet Access (HSPA), Worldwide Interoperability for Microwave Access (WiMAX), Long Term Evolution (LTE) standard, others defined by various standard-setting organizations, other long-range protocols, or other data transfer technology.

[0089] “Processor” refers to any circuit or virtual circuit (a physical circuit emulated by logic executing on an actual processor) that manipulates data values according to control signals (e.g., “commands”. “op codes”, “machine code”, etc.) and which produces corresponding output signals that are applied to operate a machine. A processor may, for example, be a Central Processing Unit (CPU), a Reduced Instruction Set Computing (RISC) processor, a Complex Instruction Set Computing (CISC) processor, a Graphics Processing Unit (GPU), a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Radio-Frequency Integrated Circuit (RFIC) or any combination thereof. A processor may further be a multi-core processor having two or more independent processors (sometimes referred to as “cores”) that may execute instructions contemporaneously.

[0090] “Machine-Storage Medium” refers to a single or multiple storage devices and/or media (e.g., a centralized or distributed database, and/or associated caches and servers) that store executable instructions, routines and/or data. The term shall accordingly be taken to include, but not be limited to, solid-state memories, and optical and magnetic media, including memory internal or external to processors. Specific examples of machine-storage media, computer-storage media and/or device-storage media include non-volatile memory, including by way of example semiconductor memory devices, e.g., erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), FPGA, and flash memory devices; magnetic disks such as internal hard disks and removable disks; magneto-optical disks; and CD-ROM and DVD-ROM disks The terms “machine-storage medium.” “device-storage medium.” “computer-storage medium” mean the same thing and may be used interchangeably in this disclosure. The terms “machine-storage media.” “computer-storage media,” and “device-storage media” specifically exclude carrier waves, modulated data signals, and other such media, at least some of which are covered under the term “signal medium.”

[0091] “Component” refers to a device, physical entity, or logic having boundaries defined by function or subroutine calls, branch points, APIs. or other technologies that provide for the partitioning or modularization of particular processing or control functions. Components may be combined via their interfaces with other components to carry out a machine process. A component may be a packaged functional hardware unit designed for use with other components and a part of a program that usually performs a particular function of related functions. Components may constitute either software components (e.g., code embodied on a machine-readable medium) or hardware components. A “hardware component” is a tangible unit capable of performing certain operations and may be configured or arranged in a certain physical manner. In various example embodiments, one or more computer systems (e.g., a standalone computer system, a client computer system, or a server computer system) or one or more hardware components of a computer system (e.g., a processor or a group of processors) may be configured by software (e.g., an application or application portion) as a hardware component that operates to perform certain operations as described herein. A hardware component may also be implemented mechanically, electronically, or any suitable combination thereof. For example, a hardware component may include dedicated circuitry or logic that is permanently configured to perform certain operations. A hardware component may be a special-purpose processor, such as a field-programmable gate array (FPGA) or an application specific integrated circuit (ASIC). A hardware component may also include programmable logic or circuitry that is temporarily configured by software to perform certain operations. For example, a hardware component may include software executed by a general-purpose processor or other programmable processor. Once configured by such software, hardware components become specific machines (or specific components of a machine) uniquely tailored to perform the configured functions and are no longer general-purpose processors. It will be appreciated that the decision to implement a hardware component mechanically, in dedicated and permanently configured circuitry, or in temporarily configured circuitry (e.g., configured by software), may be driven by cost and time considerations. Accordingly, the phrase “hardware component” (or “hardware-implemented component”) should be understood to encompass a tangible entity, be that an entity that is physically constructed, permanently configured (e.g., hardwired), or temporarily configured (e.g., programmed) to operate in a certain manner or to perform certain operations described herein. Considering embodiments in which hardware components are temporarily configured (e.g., programmed), each of the hardware components need not be configured or instantiated at any one instance in time. For example, where a hardware component comprises a general-purpose processor configured by software to become a special-purpose processor, the general-purpose processor may be configured as respectively different special-purpose processors (e.g., comprising different hardware components) at different times. Software accordingly configures a particular processor or processors, for example, to constitute a particular hardware component at one instance of time and to constitute a different hardware component at a different instance of time. Hardware components can provide information to, and receive information from, other hardware components. Accordingly, the described hardware components may be regarded as being communicatively coupled. Where multiple hardware components exist contemporaneously, communications may be achieved through signal transmission (e.g., over appropriate circuits and buses) between or among two or more of the hardware components. In embodiments in which multiple hardware components are configured or instantiated at different times, communications between such hardware components may be achieved, for example, through the storage and retrieval of information in memory structures to which the multiple hardware components have access. For example, one hardware component may perform an operation and store the output of that operation in a memory device to which it is communicatively coupled. A further hardware component may then, at a later time, access the memory device to retrieve and process the stored output. Hardware components may also initiate communications with input or output devices, and can operate on a resource (e.g., a collection of information). The various operations of example methods described herein may be performed, at least partially, by one or more processors that are temporarily configured (e.g., by software) or permanently configured to perform the relevant operations. Whether temporarily or permanently configured, such processors may constitute processor-implemented components that operate to perform one or more operations or functions described herein. As used herein, “processor-implemented component” refers to a hardware component implemented using one or more processors. Similarly, the methods described herein may be at least partially processor-implemented, with a particular processor or processors being an example of hardware. For example, at least some of the operations of a method may be performed by one or more processors 1004 or processor-implemented components. Moreover, the one or more processors may also operate to support performance of the relevant operations in a “cloud computing” environment or as a “software as a service” (SaaS). For example, at least some of the operations may be performed by a group of computers (as examples of machines including processors), with these operations being accessible via a network (e.g., the Internet) and via one or more appropriate interfaces (e.g., an API). The performance of certain of the operations may be distributed among the processors, not only residing within a single machine, but deployed across a number of machines. In some example embodiments, the processors or processor-implemented components may be located in a single geographic location (e.g., within a home environment, an office environment, or a server farm). In other example embodiments, the processors or processor-implemented components may be distributed across a number of geographic locations.

[0092] “Carrier Signal” refers to any intangible medium that is capable of storing, encoding, or carrying instructions for execution by the machine, and includes digital or analog communications signals or other intangible media to facilitate communication of such instructions. Instructions may be transmitted or received over a network using a transmission medium via a network interface device.

[0093] “Computer-Readable Medium” refers to both machine-storage media and transmission media. Thus, the terms include both storage devices/media and carrier waves/modulated data signals. The terms “machine-readable medium,” “computer-readable medium” and “device-readable medium” mean the same thing and may be used interchangeably in this disclosure.

[0094] “Client Device” refers to any machine that interfaces to a communications network to obtain resources from one or more server systems or other client devices. A client device may be, but is not limited to, a mobile phone, desktop computer, laptop, portable digital assistants (PDAs), smartphones, tablets, ultrabooks, netbooks, laptops, multi-processor systems, microprocessor-based or programmable consumer electronics, game consoles, set-top boxes, or any other communication device that a user may use to access a network.