Abstract:
Remote control units are used to interact with a variety of devices. Modeling of the usage of a remote control unit while interacting with a device helps in (a) redesigning the remote for better usability; (b) dynamic adapting of the remote to provide improved interactions; and (c) characterizing the usage behaviors. In particular, it is very popular to use remote control units to interact with TVs and PVR devices. A system and method for the modeling of a remote usage involves the use of both pre-defined models and discovered models. Specifically, a pattern of usage of a remote control unit is abstracted to be one of either a pre-defined model or a discovered model. The model discovery involves the process of generalization based on a set of particular remote control unit usage patterns. The labels associated with the models help in characterizing the remote control unit usage patterns.

Description:
FIELD OF THE INVENTION 
     The present invention relates to usage analysis in general and more particularly, the analysis of remote control unit usage. Still more particularly, the present invention is related to a system and method for the analysis of usage of a remote control unit for operating and controlling of a device. 
     BACKGROUND OF THE INVENTION 
     The usage of remote control units to operate and control devices is very common. And, this is more so with home appliances. A typical home has multiple appliances such as refrigerators, air conditioners, televisions, and personal video recorders and players. Further, each appliance has a specialized remote control unit to help operate and control the related appliance. Let us consider a television remote control unit. A typical such remote provides the functional support such as for the following: browse (to browse through the channels), swap (to swap a channel with the last viewed channel), increase volume, decrease volume, jump to a particular channel, power on, power off, and set timer. The analysis of the way a remote is used to operate and control a television provides an insight into the user behavior. This insight helps greatly in general in content personalization, and in particular in content targeting, say for example, ad targeting. The requirement is to study carefully the remote usage data so as to determine the specific usage patterns hidden in the data. There are two kinds of usage patterns: (i) one that falls into a generic category of patterns; these are the patterns typically determined in a top down manner based on the expected user behavior when under particular mental state and expanded based on observed data; (ii) the other that falls into a specific (user-specific) category of patterns; these patterns are typically determined completely based on the observed data (without possibly a recourse to mental states). These models depict the abstracted behavior of users leading to an effective content (and in particular, ads) targeting. Note that the usage of the term “user” is in generic sense: for example, in a home context, “user” refers collectively to everybody in a home who operates a remote. The present invention addresses the issues of exploiting top-down (generic) models and discovering bottom-up (specific) models so as to effectively characterize a remote control unit usage. 
     DESCRIPTION OF RELATED ART 
     U.S. Pat. No. 7,260,823 to Schlack; John A. (Southampton, Pa.), Sutton; Andrew (Norristown, Pa.), Rampulla; Andrew J (Quakertown, Pa.), Eldering; Charles A (Doylestown, Pa.) for “Profiling and identification of television viewers” (issued on Aug. 21, 2007 and assigned to Prime Research Alliance E., Inc. (Tortola, VG)) describes an approach for profiling a television viewer by monitoring and processing, locally at a television viewing environment, the viewer&#39;s interactivity (for example, via a remote control unit) with the television viewing environment. 
     U.S. Pat. No. 7,092,926 to Cerrato; Dean E. (Boston, Mass.) for “Method and apparatus for identifying unique client users from user behavioral data” (issued on Aug. 15, 2006 and assigned to Sedna Patent Services, LLC (Philadelphia, Pa.)) describes an approach for identifying a current user of a terminal device from a group of possible users based on a database containing multiple user input pattern profiles of prior user inputs to the terminal device. 
     U.S. Pat. No. 6,286,140 to Ivanyi; Thomas P. (New York, N.Y.) for “System and method for measuring and storing information pertaining to television viewer or user behavior” (issued on Sep. 4, 2001) describes a system for monitoring television viewer behavior by generating of events such as “a channel change,” and “a volume change” and storing of these timed events. 
     “Modeling User Behaviour by Planning” by Milani, A. and Silvia S. (appeared in Proceedings of World Academy of Science, Engineering and Technology, Volume 28, April 2008) describes the user behavior recognition as a planning problem and introduces a technique for transforming a timed finite state automata description of the behavior into a numerical parameter planning model. 
     “A Target Advertisement System based on TV Viewer&#39;s Profile Reasoning” by Lim, J., Kim, M., Lee, B., Kim, M., Lee, H., and Lee, H. (appeared in Multimedia Tools and Applications Journal, Volume 36, Numbers 1-2/January, 2008, Springer Netherlands) describes a user profile reasoning method for TV viewers based on genre preferences and TV viewing times for TV viewer&#39;s groups in different genders and ages. 
     “SSM: A Frequent Sequential Data Stream Patterns Miner” by Ezeife, C. I. and Monwar, M. (appeared in Proceedings of the EEE Symposium on Computational Intelligence and Data Mining, 2007 (CIDM 2007), Honolulu, Hi., USA, 1-5 Apr. 2007) describes the process of discovering frequent sequential patterns in data sequences as found in applications like web log access sequences. 
     The known systems do not address the various issues related to the modeling of a remote control unit usage in order to be able to map the same onto a user behavior without using any support data such as Electronic Program Guide and Content related information (in the case of a television). The present invention provides a system and method for addressing these issues in order to effectively exploit a plurality of pre-defined models as well as discovering user-specific models. 
     SUMMARY OF THE INVENTION 
     The primary objective of the invention is to analyze a remote control unit usage data related to a user in order to assess a plurality of behaviors exhibited by the user. 
     One aspect of the invention is to analyze the remote control unit usage related to a particular operating (say, a TV viewing) session to determine session-specific state machine. 
     Another aspect of the invention is to describe a remote control unit usage based on a plurality of basic events and a plurality of meta events, wherein each meta event is an abstraction of a plurality of basic events. 
     Yet another aspect of the invention is to describe a remote control unit usage data based on a two-level state machine, wherein the first level state machine is based on meta events, and the second level state machine is based on basic events with each node of the first level state machine being associated with a second level state machine. 
     Another aspect of the invention is to match a session-specific state machine against a plurality of pre-defined abstracted remote control unit usage models. 
     Yet another aspect of the invention is to define a matching of a session-specific state machine with respect to a pre-defined model based on two properties of the model, namely, structural properties and temporal properties. 
     Another aspect of the invention is to merge a plurality of session-specific state machines. 
     Yet another aspect of the invention is to discover a plurality of user-specific remote control unit usage models based on remote control unit usage data related to a plurality remote operating sessions. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  depicts an illustrative TV/STB scenario. 
         FIG. 2  depicts an illustrative Remote Usage Modeling System. 
         FIG. 3  depicts illustrative basic events and meta-events. 
         FIG. 3   a  depicts an illustrative characterization of a session. 
         FIG. 3   b  depicts illustrative representation of a session and a remote state machine. 
         FIG. 4  depicts an illustrative data set. 
         FIG. 4   a  depicts another illustrative data set. 
         FIG. 5  depicts an illustrative named pre-defined model. 
         FIG. 5   a  depicts another illustrative named pre-defined model. 
         FIG. 6  provides an approach for session modeling. 
         FIG. 7  provides an approach for session matching based on structural properties. 
         FIG. 7   a  provides an approach for session matching based on temporal properties. 
         FIG. 8  provides an approach for session merging. 
         FIG. 9  provides an approach for building a user-specific model. 
         FIG. 10  depicts illustrative results. 
         FIG. 10   a  depicts illustrative session data for model discovery. 
         FIG. 10   b  depicts illustrative clusters for model discovery. 
         FIG. 10   c  depicts an illustrative model discovery. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Remote control units are very popular handheld units that are used to control the operations of a variety of devices. Specifically, such units are used extensively with home appliances such as air conditioners and televisions. In particular, remote control units for televisions have addressed the functional requirements extremely well as so much of variety exists in channels being delivered, and at the same time televisions have also rich functional controls. This means that a user viewing a TV uses the remote control unit somewhat more frequently and there is an opportunity to analyze such a remote control unit usage data to characterize and subsequently predict the behavior. There are a variety of applications of the user behavior characterization: for example, if a user behavior is predicted to be one of “restlessness,” it may be appropriate to target ads that take into account this expected behavior. Another use of the analysis of a remote control unit usage data is to better design and dynamically adapt the remote control unit to provide improved interactions. 
     Remote control unit usage data is characterized based on a set of events associated with the remote control unit interactions. In order to better model the usage data, the following are proposed: (a) define and use meta-events in modeling: a meta-event is an abstract event standing for a set of basic events; and (b) define and use the notion of two-level state machine, called as remote state machine (RSM): an RSM is a state machine in which the first level state machine is based on meta-events and each node in this first level stands for a meta-event; and the second level state machine is based on basic events and a second level state machine is associated with each node of the first level state machine. The analysis of remote control unit usage data leads to the defining of an RSM based on the usage data. Similarly, both the pre-defined models and discovered models are also RSMs. Note that session model, session-specific state machine, and remote state machine (RSM) are used interchangeably. Also, an event and basic event are also used interchangeably. Further, some times, remote control unit is referred just as remote. 
       FIG. 1  depicts an illustrative TV/STB scenario. In this scenario, a remote control unit ( 100 ) is used to interact with a set-top box (STB) ( 110 ) to control the functionality of a television ( 120 ). A typical STB supports various functionalities that include the receiving and displaying of the selected channel contents. One of the important functionalities is to support RUM (Remote Usage Modeling) subsystem ( 130 ) that makes use of a database ( 140 ) to help build a session-specific state machine and determine an appropriate model that matches best with the session-specific state machine. In particular, RUM subsystem takes a session usage data as input to achieve model based annotation of the session. This annotation is used by another subsystem ( 150 ) to help select appropriate ads based on an STB database ( 160 ). 
       FIG. 2  depicts an illustrative Remote Usage Modeling System. The RUM System ( 200 ) comprises of a variety of modules to help capture, analyze, and label a session. The database ( 210 ) consists of Session database to provide session information, Pre-defined models, and Discovered models. The main modules of RUM are: Session Capture ( 220 ) that obtains session-specific usage data from a database; Session Analysis ( 230 ) analyzes the captured session-specific usage data and prepares for further processing; Session State Machine Building ( 240 ) determines the basic events and meta-events that are part of the usage data, constructs an RSM based on the data, and processes the constructed RSM to eliminate noisy and erroneous remote interactions; Session Matching ( 250 ) matches the constructed RSM against a set of pre-defined models to determine if any of the pre-defined models can be used to model the session-specific remote usage data; Session Merging ( 260 ) module helps in merging two or more session-specific remote usage data to arrive at a combined model; and finally, Modeling Building ( 270 ) analyzes a set of session-specific remote usage data to discover one or more user-specific models that better describe the usage data as compared with the set of pre-defined models. 
       FIG. 3  depicts illustrative basic events and meta-events. An illustrative set of basic events ( 300 ) includes events such as Channel+ and Volume−. In order to be able to process the session-specific usage data in a more effective manner, a related set of basic events are grouped to form a meta-event. Some illustrative meta-events ( 310 ) include Sound and Channel-Change. The annotations of a session-specific usage data is based on the labels associated with the pre-defined models and discovered models. These labels suggest about the possible psychological states of mind while viewing TV. Some of the illustrative psychological states ( 320 ) include “Leisurely Watching” and “Focused Watching.” 
       FIG. 3   a  depicts an illustrative characterization of a session. On power-on ( 1 ), there is a frequent usage of a remote control unit ( 2 ) leading to a settling down on a channel ( 3 ). After a while, there is again a frequent usage of the remote control ( 4 ) leading to a short stable period ( 5 ) before power-off ( 6 ). 
       FIG. 3   b  depicts illustrative representation of a session and a remote state machine. Information related to a Session is as follows: 
     (i) Consider a remote control unit usage behavior depicted in  FIG. 3   a.    
     (ii) The figure depicts activities performed using the remote between power-on (indicated by circled 1) and power-off (indicated by circled 6); 
     (iii) There is a brief period of hyper-activity of remote usage (circled 2) before a significant period of remote inactivity (circled 3); 
     (iv) This follows another period of hyper-activity (circled 4), and a brief period of inactivity (circled 5) before power-off; 
     (v) Given this, a session is defined as a period of remote activity followed by a period of remote inactivity; 
     (vi) Examples: Circled 1, 2, and 3 form a session and circled 4, 5, and 6 form another session; 
     (vii) Some times, it is useful to have a lower bound on the duration: Time period of circled 3 to be greater than a pre-defined threshold; 
     (viii) Each basic event has a time-stamp, label, and one or more attributes; 
     (ix) Session data is a sequence of basic events wherein each basic event is a remote key press down to press up; 
     A basic event is represented as 
     
         
         
           
             &lt;EventID, StartTime, EndTime, InitialAttributes, FinalAttributes&gt; 
             Note that the attribute values are optional;
 
Session State Machine:
 
(i) This is based on remote state machine (RSM): an RSM is a multi-level graph wherein there is a labeled and weighted graph at each level (hierarchical state machines);
 
(ii) In a typical representation, there are two levels:
 
(iiA) Level 1 (L1) RSM is based on meta-events with each node in L1 representing a meta-event;
 
(iiB) Level 2 (L2) RSM is based on basic events in which each node stands for a basic event;
 
(iiC) Each L2 RSM is associated with a node of an L1 RSM and hence, basic events of an L2 RSM are bound by a meta-event;
 
(iiD) Each node in an RSM has three attributes &lt;N, T, E&gt;: N—stands for number visits to the node during a session; T—stands for an aggregated time of visits; and E—stands for the number of edges at N;
 
           
         
       
    
       FIG. 4  depicts an illustrative data set. Note that, for illustrative purposes, subsession and meta-event information are also depicted in the figure. 
     Similarly,  FIG. 4   a  depicts another illustrative data set. 
       FIG. 5  depicts an illustrative named model. Observe that the model depicts five meta-events, namely, Sound, Display, Channel-Change, Browse, and Application-Load. The state machine based on these five meta-events forms a level 1 state machine. Each node in the level 1 state machine has an associate level 2 state machine. For example, associated with Display meta-event, the figure depicts a state machine based on the following basic events: Picture, Zoom, and Aspect. Observe further that, each node (in both level 1 state machine and level 2 state machine) has three attributes based on &lt;N, T, E&gt;. Named models are typically part of a pre-defined database of models. 
     Similarly,  FIG. 5   a  depicts another illustrative named model. 
       FIG. 6  provides an approach for session modeling. This involves analyzing of session-specific remote control unit usage data to build an RSM. 
     The main objective is to analyze a session data to generate a session-specific state machine. 
     The inputs include the following;
         SessionData: A sequence of Events=(E 1 , E 2 , . . . , Ex)   Meta-Event Database comprising basic event to meta-event mapping;       

     The output is a SessionStateMachine: L1RSM; 
     For each event Ei in SessionData 
     Step 1: Obtain the corresponding meta-event (Me); 
     Step 2: Locate the node N 1  in L1RSM corresponding to Me; 
     Step 3: If there is no such node, Create a new node N 1  in L1RSM; 
     Step 4: Obtain the L2RSM corresponding to N 1 ; 
     Step 5: Locate the node N 2  in L2RSM corresponding to Ei; 
     Step 6: If there is no such node, Create a new node N 2  in L2RSM; 
     Step 7: Update L2RSM with attributes of Ei; 
     Step 8: Update the node N 2  values for &lt;N, T, E&gt;; 
     Step 9: Update the node N 1  values for &lt;N. T, E&gt;; 
     // Analyze the created RSM, to remove noisy events such as those key presses that // are performed by mistake 
     For each node N 1  in L1 RSM
     Step 1: Obtain the L2RSM corresponding to N 1 ;   Step 2: Analyze L2RSM and compute the typical &lt;N′, T′, E′&gt;;   The typical value computation takes into account the factors such as the value of &lt;N, T, E&gt; across the nodes of the RSM, the meta-event under consideration, and the basic event under consideration;   Step 3: For each node N 2  in L2RSM   Step 3a: Obtain &lt;N, T, E&gt;   Step 3b: If &lt;N, T, E&gt; is not close to &lt;N′, T′, E′&gt;,
       Record the deviation and mark N 2  for deletion;   
       Step 3c: Arrange the nodes marked for deletion in L2RSM in the descending order of their deviations;   Step 3d: Select a pre-defined number of nodes and delete them from L2RSM;   

       FIG. 7  provides an approach for session matching based on structural properties. 
     The objective is to match a session state machine against a set of pre-defined models; 
     The input includes the following:
         SessionStateMachine: L1RSM;   SBM={BM 1 , BM 2 , . . . , BMx} is a set of labeled pre-defined models;       

     The output is SessionModels that is a subset of SBM such that each element of the subset closely matches with L1RSM; 
     For each BMi in SBM
     Step 1: Perform Structural Matching to obtain Si;   Step 2: Perform Temporal Matching to obtain Ti;   Step 3: Compute Di as W1*Si+W2*Ti; Di is the overall matching error associated with BMi;   Order BMi&#39;s based on Di&#39;s;   Select a pre-defined number of models BMm&#39;s with best Dm&#39;s that is within a pre-defined threshold as SessionModels;   

     Observe that the matching is based on two aspects: Structural aspect and temporal aspect. When two RSMs are matched against each other, structural and temporal matching is performed at both levels: matching of level 1 structural aspects; matching of level 1 temporal aspects; matching of level 2 structural aspects; and matching of level 2 temporal aspects. 
     Structural Matching 
     For each node N 1  in BMi 
     Step 1: Find the corresponding node N 2  in L1RSM; 
     Step 2: Obtain &lt;N, T, E&gt; associated with N 1 ; 
     Step 3: Obtain &lt;N′, T′, E′&gt; associated with N 2 ; 
     Step 4: Find distance X 1  between N 1  and N 2  based on &lt;N, T, E&gt; and &lt;N′, T′, E′&gt;; 
     Step 5: Let L2R(N 1 ) be the L2RSM associated with N 1 ; 
     Step 6: Let L2R(N 2 ) be the L2RSM associated with N 2 ; 
     //Find the structure based distance Y 1  between L2R(N 1 ) and L2R(N 2 ) by iterating //over the structure 
     Step 7: For each node N 11  in L2R(N 1 ) 
     Step 7a: Find the corresponding node N 12  in L2R(N 2 ) 
     Step 7b: Obtain &lt;N, T, E&gt; associated with N 11 ; 
     Step 7c: Obtain &lt;N′, T′, E′&gt; associated with N 12 ; 
     Step 7d: Find distance Y 1  between N 11  and N 12  based on &lt;N, T, E&gt; and &lt;N′, T′, E′&gt;; 
     Step 7e: Add Y 1  to Y; 
     Step 8: Add X 1 , Y to Si; 
     Note that Si is the overall structural matching error associated with BMi. 
       FIG. 7   a  provides an approach for session matching based on temporal properties. 
     The input for temporal matching are a pre-defined model BMi and a session state machine L1RSM; 
     The output is a measure Ti based on temporal matching; 
     Temporal Matching 
     
         
         Let BMiSeq be a temporal sequence associated with BMi without considering the L2RSMs associated with the nodes of BMi; 
         Let L1Seq be a temporal sequence associated with L1RSM without considering the associated L2RSMs with the nodes of L1RSm; 
         Apply a warping technique based on, say, dynamic programming, to determine minimum matching error; use a distance measure based on &lt;N, T, E&gt; associated with the nodes of BMiSeq and L1Seq, and distance between a pair of meta-events based on a distance metric; 
         Let TE 1  be the minimum match error; 
       
    
     For each node Ni in BMi
     Step 1: Find the corresponding node N 2  in L1RSM;   Step 2: Let L2R(N 1 ) be the L2RSM associated with N 1 ;   Step 3: Let L2R(N 2 ) be the L2RSM associated with N 2 ;   Step 4: Let L2R(N 1 )Seq be a temporal sequence associated with L2R(N 1 );   Step 5: Let L2R(N 2 )Seq be a temporal sequence associated with L2R(N 2 );   Step 6: Apply a warping technique based on, say, dynamic programming, to determine minimum matching error; use a distance measure based on &lt;N, T, E&gt; associated with the nodes of L2R(N 1 )Seq and L2R(N 2 )Seq, and distance between a pair of basic events based on a distance metric;   Step 7: Let E 2  be the minimum match error;   Step 8: Add E 2  to TE 2 ;   Ti=TE 1 +TE 2 ; Ti is the overall temporal matching error associated with BMi;   

       FIG. 8  provides an approach for session merging. The session merging is to achieve in identifying an abstract model given a plurality of session models. 
     Given: A plurality of session models SL1RSM={L11, L12, . . . , L1x}, identify an abstract model, L1M 
     // Level 1 Structural Merging 
     For each node N 1  in L11,
     Step 1: Obtain &lt;N 1 , T 1 , E 1 &gt; associated with Ni;   Step 2: Obtain a plurality of &lt;Ni, Ti, Ei&gt;&#39;s associated with the node corresponding to Ni in session models L12, . . . , L1x;   Step 3: Compute &lt;Ni′, Ti′, Ei′&gt; as the centroid of &lt;Ni, Ti, Ei&gt; with 1&lt;=I&lt;=X and associate the same with Ni of L1M;
 
// Level 1 Time Distribution
   

     For each node Ni in L1M,
     Step 1: Obtain &lt;Ni, Ti, Ei&gt; associated with Ni;   Step 2: Obtain the sequence &lt;&lt;TS 11 , TE 11 &gt; . . . &lt;TS 1   y , TE 1   y&gt; &gt; associated with the node N 1 ′ of L11, wherein N 1 ′ corresponds with Ni;   Step 3: Obtain the sequences associated with the node corresponding to Ni in session models L12, . . . , L1x;   Step 4: Based on the above time sequences, determine a sequence that has least mismatch error and is closely consistent with &lt;Ni, Ti, Ei&gt;;
       This results in time sequence indicating the visits to Ni;   
       Step 5: Associate this time sequence with Ni of L1M;
 
//Adjusting for Inconsistency
   Compute an inconsistency measure based on the plurality of &lt;N, T, E&gt;&#39;s associated with the nodes of L1M; Note that the inconsistency measure accounts for both structural and temporal inconsistency associated with L1M;   Adjust minimally the plurality of &lt;N, T, E&gt;&#39;s associated with the nodes of L1M to account for the inconsistency measure;
 
// Constraint Based Level 2 Merging
   

     For each node Ni in L1M,
     Step 1: Obtain SL2RSM containing a plurality of L2RSM&#39;s associated with the node corresponding to Ni in session models L11, l12, . . . , L1x;   Step 2: Obtain the sequence TS=&lt;&lt;TSi 1 , TEi 1 &gt;, . . . , &lt;TSiy, TEiy&gt;&gt; associated with Ni;   Step 3: For each L2RSM in SL2RSM,   Step 3a: Bind L2RSM to be within TS by dropping events that are outside the bound and Modifying events if necessary;   Step 4: Cluster L2RSM&#39;s in SL2RSM based on structural and temporal similarity;   Step 5: Order clusters on their size;   Step 6: Select a pre-defined number of clusters from the top of the ordered clusters;   Step 7: Transform the absolute timestamps associated with the events to relative timestamps;   Step 8: Bind the selected clusters with relative timestamps to Ni;   

       FIG. 9  provides an approach for building a user-specific model. The objective is to discover a plurality of user-specific models given a plurality of session-specific state machines. 
     Given a plurality of session-specific state machines, SL1={L11, L12, . . . , L1x}; and let SBM={BM 1 , BM 2 , . . . , BMx} be a set of labeled pre-defined behavioral models; 
     Output: A plurality of abstract models, SL1M; 
     For each L1i in SL1, 
     Step 1: Determine whether L1i is close to any model in SBM; 
     Step 2: If not, Make L1i part of TL1; 
     For each L1i in TL1, 
     Step 1: Make L1i part of T 1 L1; 
     Step 2: For each L1j in TL1, 
     Step 2a: If L1j is similar to L1i, Make L1j part of T 1 L1; 
     Step 3: Session Merge based on T 1 L1 to generate an abstract model L1M; 
     Step 4: Make L1M part of SL1M; 
       FIG. 10  depicts illustrative results. In this case, the session data depicted in  FIG. 4  and  FIG. 4   a  are matched against models depicted in  FIG. 5  and  FIG. 5   a . The values in the figure indicate (1—overall match error). Observe that each session data is divided into two subsessions and Session  1   a  matches well with Model  1  (Restlessness) while Session  1   b  matches best with Model  2  (Focused Watch). 
       FIG. 10   a  depicts an illustrative session data for model discovery. Observe that there are 20 sessions each depicting a sequence of events. 
       FIG. 10   b  depicts an illustrative set of clusters for model discovery. Note that these clusters are based on the analysis of data related to a plurality of sessions depicted in  FIG. 10   a . There are four clusters in which Cluster ID  1  has a maximum size representing information related to eight sessions. 
       FIG. 10   c  depicts an illustrative model discovery. Note that this discovered model is based on Cluster Id  1  depicted in  FIG. 10   b . The discovered model depicts both level-1 state machine and a level-2 state machine for each of the nodes of the level-1 state machine. 
     Thus, a system and method for remote control unit usage modeling is disclosed. Although the present invention has been described particularly with reference to the figures, it will be apparent to one of the ordinary skill in the art that the present invention may appear in any number of systems that identifies an interaction behavior of a user while operating and controlling a device using a remote control unit. It is further contemplated that many changes and modifications may be made by one of ordinary skill in the art without departing from the spirit and scope of the present invention.