Device, system, and method of detecting identity of a user based on motor-control loop model. A method includes: during a first session of a user who utilizes a pointing device for interacting with a computerized service, monitoring the pointing device dynamics and gestures of the user; based on the monitored dynamics and gestures, estimating parameters that characterize a sensorimotor control loop model of the user; storing in a database a record indicating that the user is associated with the parameters that characterize the sensorimotor control loop model of the user.
Please help me write a proper abstract based on the patent claims. CLAIM: 1. A method comprising: (a) during a usage session of a user who utilizes a pointing device for interacting with a computerized service, monitoring on-screen movements; (b) analyzing the on-screen movements, (I) to derive from them estimated dynamics of the pointing device as utilized by said user, and (II) to determine motor capabilities and cognitive capabilities that characterize the utilization of said pointing device by said user; (c) differentiating between (i) said user and (ii) one or more other users, based on a subsequent analysis of subsequent on-screen movements which correspond to device dynamics that do not match at least one of: (I) the motor capabilities that were identified for said user based on his prior on-screen movements, (II) the cognitive capabilities that were identified for said user based on his prior on-screen movements. 2. The method of claim 1, wherein the analyzing of step (b) comprises: defining a sensorimotor control loop model by analyzing the on-screen movements of an on-screen pointer. 3. The method of claim 1, wherein the analyzing of step (b) comprises: defining a sensorimotor control loop model by analyzing the on-screen movements of an on-screen pointer; by analyzing dynamics of the pointing device, determining (AA) at least one sensorimotor control loop parameter that characterizes utilization of said pointing device by said user, and (BB) at least one parameter corresponding to a noise characteristic of the sensorimotor control loop that characterizes utilization of said pointing device by said user; generating a function that describes the sensorimotor control loop model that causes said on-screen movements of said on-screen pointer. 4. The method of claim 1, wherein the analyzing of step (b) comprises: based on the monitored pointing device dynamics and gestures of said user, estimating parameters of a Fitts' s Law function indicating ability of said user to rapidly reach an on-screen target; based on the estimated parameters of the Fitts' s Law function of said user, differentiating between said user and another user interacting with said computerized service. 5. The method of claim 1, wherein the analyzing of step (b) comprises: estimating parameters of a sensorimotor control loop of said user, by estimating the parameters that characterize the sensorimotor control loop as a function of at least one of: (I) translation error, (II) current velocity, and (III) motor control noise, based on monitored pointing device dynamics and gestures. 6. The method of claim 1, wherein the analyzing of step (b) comprises: estimating parameters of a sensorimotor control loop of said user, by estimating the parameters that characterize the sensorimotor control loop as a function of at least two of: (I) translation error, (II) current velocity, and (III) motor control noise, based on monitored pointing device dynamics and gestures. 7. The method of claim 1, wherein the analyzing of step (b) comprises: estimating parameters of a sensorimotor control loop of said user, by estimating the parameters that characterize the sensorimotor control loop as a function of all of: (I) translation error, (II) current velocity, and (III) motor control noise, based on monitored pointing device dynamics and gestures. 8. The method of claim 1, comprising: estimating parameters of a first sensorimotor control loop, associated with pointing device based interactions of a first user during a first usage session at a first computerized service; estimating parameters of a second sensorimotor control loop, associated with pointing device based interactions of a second user during a second session at a second, different, computerized service; if the parameters of the first sensorimotor control loop match the parameters of the second sensorimotor control loop, then determining that the first user and the second user are the same person. 9. The method of claim 1, comprising: based on the monitored pointing device dynamics and gestures of said user, estimating both movement agility and movement dexterity of said user; based on both the estimated movement agility and the estimated movement dexterity of said user, differentiating between said user and another user interacting with said computerized service. 10. A process comprising: (a) monitoring spatial acceleration of a mobile electronic device, that is utilized by a user for interacting with a computerized service, by an accelerometer of the mobile electronic device; (b) based on analysis of the spatial acceleration of the mobile electronic device, generating a function that corresponds to a sensorimotor control loop of said user who utilizes spatial gestures to interact with said mobile electronic device; (c) differentiating between said user, and one or more other users, based on whether or not fresh gestures of user interactions correspond to said sensorimotor control loop of said user. 11. The process of claim 10, wherein step (b) comprises: based on an analysis of the spatial acceleration of the mobile electronic device, determining motor capabilities and cognitive capabilities that characterize the utilization of said mobile electronic device by said user having said sensorimotor control loop. 12. The process of claim 10, wherein the analyzing of step (b) comprises: determining parameters of the sensorimotor control loop of said user, by estimating the parameters that characterize the sensorimotor control loop as a function of at least one of: (I) translation error, (II) current velocity, and (III) motor control noise, based on monitored spatial acceleration of said mobile electronic device while said user interacts with the mobile electronic device. 13. The process of claim 10, wherein step (b) comprises: generating the function that corresponds to the sensorimotor control loop of said user, based on both: (I) analysis of the spatial acceleration of the mobile electronic device as sensed by said accelerometer of the mobile electronic device; and also (II) analysis of spatial orientation of the mobile electronic device as sensed by a gyroscope of the mobile electronic device. 14. The process of claim 10, wherein step (b) comprises: estimating the sensorimotor control loop of said user by utilizing at least a function that takes into account at least: (I) a first trajectory parameter indicating spatial velocity of the mobile electronic device, and (II) a second trajectory parameter indicating translation error. 15. The process of claim 10, wherein step (b) comprises: estimating the sensorimotor control loop of said user by utilizing at least a function that takes into account at least: (I) a first trajectory parameter indicating spatial velocity of the mobile electronic device, and (II) a second trajectory parameter indicating noise. 16. The process of claim 10, comprising: performing an analysis of (I) user interactions with the mobile electronic device, and (II) spatial acceleration of the mobile device; based on said analysis, determining a user-specific characteristic that quantifies a level of eye-hand coordination of said user. 17. The process of claim 10, comprising: performing an analysis of (I) user interactions with the mobile electronic device, and (II) spatial acceleration of the mobile electronic device as sensed by the accelerometer of the mobile electronic device, and (III) spatial orientation of the mobile electronic device as sensed by a gyroscope of the mobile electronic device; based on said analysis, determining a user-specific characteristic that quantifies a level of eye-hand coordination of said user. 18. A process comprising: (a) monitoring spatial orientation of a mobile electronic device, that is utilized by a user for interacting with a computerized service, by a gyroscope of the mobile electronic device; (b) based on analysis of the spatial orientation of the mobile electronic device, generating a function that corresponds to a sensorimotor control loop of said user who utilizes spatial gestures to interact with said mobile electronic device; (c) differentiating between said user, and one or more other users, based on whether or not fresh gestures of user interactions correspond to said sensorimotor control loop of said user. 19. The process of claim 18, wherein step (b) comprises: based on an analysis of the spatial orientation of the mobile electronic device, determining motor capabilities and cognitive capabilities that characterize the utilization of said mobile electronic device by said user having said sensorimotor control loop. 20. The process of claim 18, wherein the analyzing of step (b) comprises: determining parameters of the sensorimotor control loop of said user, by estimating the parameters that characterize the sensorimotor control loop as a function of at least one of: (I) translation error, (II) current velocity, and (III) motor control noise, based on monitored spatial orientation of said mobile electronic device while said user interacts with the mobile electronic device. 21. The process of claim 18, wherein step (b) comprises: generating the function that corresponds to the sensorimotor control loop of said user, based on both: (I) analysis of the spatial acceleration of the mobile electronic device as sensed by an accelerometer of the mobile electronic device; and also (II) analysis of spatial orientation of the mobile electronic device as sensed by said gyroscope of the mobile electronic device. 22. The process of claim 18, wherein step (b) comprises: estimating the sensorimotor control loop of said user by utilizing at least a function that takes into account at least: (I) a first trajectory parameter indicating spatial orientation of the mobile electronic device, and (II) a second trajectory parameter indicating translation error. 23. The process of claim 18, wherein step (b) comprises: estimating the sensorimotor control loop of said user by utilizing at least a function that takes into account at least: (I) a first trajectory parameter indicating spatial orientation of the mobile electronic device, and (II) a second trajectory parameter indicating noise. 24. The process of claim 18, comprising: performing an analysis of (I) user interactions with the mobile electronic device, and (II) spatial orientation of the mobile electronic device as sensed by the gyroscope of the mobile electronic device; based on said analysis, determining a user-specific characteristic that quantifies a level of eye-hand coordination of said user. 25. The process of claim 18, comprising: performing an analysis of (I) user interactions with the mobile electronic device, and (II) spatial acceleration of the mobile electronic device as sensed by an accelerometer of the mobile electronic device, and (III) spatial orientation of the mobile electronic device as sensed by the gyroscope of the mobile electronic device; based on said analysis, determining a user-specific characteristic that quantifies a level of eye-hand coordination of said user. 26. A method comprising: (a) during a usage session of a user who utilizes a pointing device for interacting with a computerized service, (a1) monitoring on-screen movements of an on-screen pointer controlled by said user, and (a2) monitoring gestures performed by said user via said pointing device; (b) based on analysis of: (b1) the on-screen movements of the on-screen pointer controlled by said user, and (b2) the gestures performed by said user via said pointing device, determining a user-specific characteristic that quantifies a level of eye-hand coordination of said user; (c) differentiating between said user, and one or more other users, based on said user-specific characteristic that quantifies the level of eye-hand coordination of said user. 27. The method of claim 26, wherein the determining of step (b) comprises: determining the user-specific characteristic that quantifies the level of eye-hand coordination of said user, based on analysis of: (b1) the on-screen movements of the on-screen pointer controlled by said user, and (b2) the gestures performed by said user via said pointing device, and (b3) spatial acceleration of the mobile electronic device as sensed by an accelerometer of said mobile electronic device. 28. The method of claim 26, wherein the determining of step (b) comprises: determining the user-specific characteristic that quantifies the level of eye-hand coordination of said user, based on analysis of: (b1) the on-screen movements of the on-screen pointer controlled by said user, and (b2) the gestures performed by said user via said pointing device, and (b3) spatial orientation of the mobile electronic device as sensed by a gyroscope of said mobile electronic device. 29. The method of claim 26, wherein the determining of step (b) comprises: determining the user-specific characteristic that quantifies the level of eye-hand coordination of said user, based on analysis of: (b1) the on-screen movements of the on-screen pointer controlled by said user, and (b2) the gestures performed by said user via said pointing device, and (b3) spatial orientation of the mobile electronic device as sensed by a gyroscope of said mobile electronic device, and (b4) spatial orientation of the mobile electronic device as sensed by a gyroscope of said mobile electronic device.