# Patent

## Title
Methods and apparatus to determine probabilistic media viewing metrics

## Abstract

Methods and apparatus to determine probabilistic media viewing metrics are disclosed herein. An example apparatus includes memory including machine reachable instructions; and processor circuitry to execute the instructions to calculate a first probability for respective ones of a plurality of panelists as having viewed media based on viewing data, the viewing data including incomplete viewing data for one or more of the panelists relative to the media; identify respective ones of a plurality of panelists as included in a demographic subgroup based on demographic data for the panelists; assign a sampling weight to the respective ones of the plurality of panelists based on the demographic data; and calculate a second probability of the demographic subgroup having viewed the media based on the first probabilities and the sampling weights for the respective ones of the plurality of panelists in the demographic subgroup.

## Background
RELATED APPLICATION
This patent arises from a continuation of U.S. patent application Ser. No. 15/385,508 (now U.S. Pat. No. 10,791,355), which was filed on Dec. 20, 2016. U.S. patent application Ser. No. 15/385,508 is hereby incorporated herein by reference in its entirety. Priority to U.S. patent application Ser. No. 15/385,508 is hereby claimed.


FIELD OF THE DISCLOSURE
This disclosure relates generally to media viewing metrics such as ratings and shares and, more particularly, to methods and apparatus to determine probabilistic media viewing metrics.
BACKGROUND
Audience viewership of, for example, a television program, may be analyzed to determine ratings and/or shares for the program. Audience viewing behavior data collected from, for example, a viewing panel, may introduce uncertainties into the analysis of the ratings and/or shares. For example there may be uncertainties as to whether a panelist is watching television and, if so, what television channel or program the panelist is watching.



BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates an example environment in which a system constructed in accordance with the teachings disclosed herein operates.
FIG. 2 is a block diagram of an example implementation of a portion of the system of FIG. 1.
FIG. 3 is a flowchart representative of example machine readable instructions that may be executed to implement the example system of FIGS. 1-2.
FIG. 4 illustrates an example processor platform that may execute the example instructions of FIG. 3 to implement the example system of FIGS. 1-2.



The figures are not to scale. Wherever possible, the same reference numbers will be used throughout the drawing(s) and accompanying written description to refer to the same or like parts.
DETAILED DESCRIPTION
Audience viewing data can be collected from a plurality of individuals or households watching, for example, television, to determine ratings and/or shares for one or more television programs. Television ratings represent a number of people (or households) with a television tuned to a particular channel or program divided by a total number of people (or households) that have a television. Thus, ratings consider a potential viewing population, or the total number of people or households that have a television. Television shares represent a percentage of people (or households) watching a particular channel or program out of a viewing population that includes the people (or households) that are watching television at a given time. Thus, determining shares includes considering a population who is watching television at a given time.
When analyzing audience viewing behavior to calculate ratings and/or shares, there may be uncertainties with respect to whether a panelist (e.g., a person in a household selected to participate in ratings research performed by, for example, The Nielsen Company (US), LLC) is watching television and, if so, what television channel and/or program he or she is watching. Uncertainties with respect to identifying audience viewing behavior can arise from, for example, co-viewing of a television program by members of the same household or a malfunction of a television panel meter collecting viewing activity data from the panelist's television. Thus, in some examples, viewing metrics such as ratings and/or shares are determined using data including uncertainties or probabilities with respect to panelist viewing behavior.
For example, for a first panelist, there may be a 50% probability that the first panelist is not watching television or a 50% that the first panelist is watching a first program. As another example, data may be collected from a second panelist indicating that the second panelist is watching television, but there may not be data as to which of a first program, a second program, or a third program the second panelist is watching. Known methods for addressing probabilities or uncertainties with respect to the viewing behavior of, for example, the first panelist and the second panelist include randomly assigning each panelist as viewing a particular television program using a Monte Carlo simulation or a variation thereof. For example, the first panelist who is either not watching television or is watching the first program may be randomly assigned as watching the first program. The second panelist who is watching one of the first program, the second program, or the third program may be randomly assigned to the second program. Thus, in some known methods, each of the first panelist and the second panelist are assigned as watching a particular program or as not watching television (e.g., using “0's” and “1's”), thereby removing uncertainties from the panelist data.
In some known methods, ratings and/or shares can be calculated based on the randomly assigned probability data (e.g., the 0's and 1's) for the first panelist, the second panelist, and/or other panelists. However, in some known methods, a Monte Carlo simulation is only performed once. As a result, ratings information does not account for the fact that the panelists could be watching other programs probabilistically. For example, if the Monte Carlo simulation is performed multiple times, the second panelist could be randomly assigned as watching the first program or the third program instead of the second program. Thus, ratings and/or shares calculated based on random assignment of panelist viewing activity may not accurately reflect a range of possible probabilistic scenarios, as the results are limited by the different scenarios that are generated.
Accuracy of such known methods could be increased if, for example, the Monte Carlo simulation is performed multiple times (e.g., thousands of times) to identify a range of possible scenarios or outcomes with respect to probabilities that a panelist is watching television, what program a panelist is watching, etc. and if the ratings calculated from the different probabilistic scenarios are averaged. However, such known methods are time-consuming and can require significant processing resources to repeat the simulation thousands of times in an effort to capture a wide range of possible probabilistic scenarios or outcomes. Even if the simulation is run multiple times, the results are still limited by the fact that ideally the simulation would be run an infinite number of times.
Examples disclosed herein provide for a determination of viewing metrics such as ratings and/or shares that accounts for substantially all possible viewing scenarios that could happen and a probability of a viewing scenario happening. For example, ratings computed using examples disclosed herein consider that the second panelist could be watching the first program, the second program, or the third program as well as the respective probabilities that the second panelist is watching the one of first, second, or third programs. Examples disclosed herein compute ratings and/or shares for one or more television programs using one or more algorithms that consider the probabilities that a panelist may or may not be watching television, may or may not be watching a certain program, etc. Some examples disclosed herein selectively adjust sampling weights assigned to a panelist in view of the probabilities that the panelist is or is not watching television, is watching a certain program, etc. so as to identify a viewing population that can be used to calculate, for example, shares despite the uncertainties in the data.
Some examples disclosed herein compute variance or covariance metrics for analysis of viewing behavior across two or more television programs. Also, some disclosed examples can analyze ratings, shares, and/or other viewing metrics for a population subgroup or panelist of interest. For example, a demographic group can be analyzed with respect to what program the demographic group is watching or what portion of the demographic group is watching a particular program.
Examples disclosed herein more accurately identify ratings and/or shares with respect to uncertainties or probabilities in viewing behavior data and reduce errors in computing ratings and/or shares as compared to approaches that consider a limited range of probabilistic scenarios, only run a Monte Carlo simulation once, etc. Examples disclosed herein improve computational efficiency and reduce processing resources in considering the many scenarios that could arise for panelists or a group of panelists. Examples disclosed herein substantially eliminate the need to run a probabilistic scenario simulation hundreds or thousands of times. Rather, examples disclosed herein generate results that substantially approximate viewing metrics as if the simulations were performed an infinite number of times. Thus, disclosed examples provide a technical improvement in the field of ratings metrics over known methods that address uncertainties in viewing data in a limited fashion.
Although examples disclosed herein are discussed in the context of media viewing metrics such as television ratings and/or shares, examples disclosed herein can be utilized in other applications. For example, examples disclosed herein could be used for other types of media than television programs, such as radio. Also, examples disclosed herein could be used in applications other than media to analyze behavior of a population with respect to, for example, buying a product such as cereal.
FIG. 1 illustrates an example system 100 for computing viewing metrics such as ratings and/or shares associated with one or more television programs. As illustrated in FIG. 1, a first household 102 includes a first panelist 104. The first household 102 can include additional panelists. The first household 102 includes a first television 106. A first panel meter 108 is communicatively coupled to the first television 106. The first television 106 can be tuned to broadcast one or more channels 110a-110n. Each of the channels 110a-110n can provide one or more media or programs 112a-112n to be viewed via the first television 106 by the first panelist 104.
The first panel meter 108 collects data from the first television 106, such as whether the first television 106 is turned on, to which of the channels 110a-110n the first television is tuned, how long the first television 106 is tuned to the selected channel 110a-110n, what time of day the first television 106 is tuned to the one of the channels 110a-110n, etc. In the example of FIG. 1, the first panelist 104 is associated with a plurality of demographics 114, such as age, gender, ethnicity, household size, etc. In some examples, the demographics 114 include data about the geographic location of the first household 102, socioeconomic status, etc. In some examples, the first panel meter 108 collects and/or stores data about the demographics 114 the first panelist 104 (e.g., via one or more user inputs with respect to the demographics 114 of the first panelist 104, census data, etc.).
The example system 100 includes a second household 116. The second household 116 includes a second panelist 118. The second household can include additional panelists. The second household 116 includes a second television 120 and a second panel meter 122 communicatively coupled to the second television 120. The second panel meter 122 collects data from the second television 120 regarding, for example, which of the channels 110a-110n the second television 120 is tuned to at a given time of day, and other data substantially as disclosed above in connection with the first television 106 and the first panel meter 108. The second meter 122 can collect and/or store data about demographics 124 associated with the second panelist 118 (e.g., age, gender, etc. of the second panelist 118).
The example system 100 can include other households in addition to the first household 102 and the second household 116 (e.g., n households 102, 116). Also any of the households 102, 116 in the example system 100 of FIG. 1 can include one or more panelists (e.g., n panelists 104, 118). Television viewing activity can be collected from any of the households in the example system 100 substantially as described herein with respect to the first and second households 102, 116 of FIG. 1.
In the example system of FIG. 1, the first panel meter 108 and the second panel meter 122 are communicatively coupled to a processor 126 (e.g., via wireless connections) to transmit return path data to the processor 126. The first panel meter 108 transmits a first data stream 128 to the processor 126 including viewing data for the first television 106 of the first household 102. The second panel meter 122 transmits a second data stream 130 to the processor 126 including viewing data for the second television 120 of the second household 102. The respective data streams 128, 130 can include data such as the channel(s) 110a-110n to which each television 106, 120 is tuned at a certain time. The first and second data streams 128, 130 can include demographic data about the panelists 104, 118 of the respective households 102, 116. As disclosed below, the processor 126 stores the data streams 128, 130 for analysis with respect to television viewing metrics.
In some examples, the first data stream 128 and/or the second data stream 130 includes data indicative of one or more uncertainties about the television viewing behavior of the first panelist 104 (or the first household 102) and/or the second panelist 118 (or the second household 116). For example, there may be uncertainty as to whether the first panelist 102 was co-viewing one of the programs 112a-112n with another member of the first household 102. As another example, there may have been a temporary technical error in the collection of data by the first and/or second panel meters 108, 122 (e.g., an inability to collect data from the television(s) 106, 120 for a period of time). Thus, at least a portion of the first data stream 128 and/or the second data stream 130 may include uncertain or probabilistic viewing activity data by the respective panelists 104, 118 (and/or households 102, 116).
The example processor 126 of FIG. 1 includes a viewing activity analyzer 132. The example viewing activity analyzer 132 calculates viewing metrics such as ratings and/or shares for one or more of the programs 112a-112n based on the data in the first data stream 128, the second data stream 130, and/or other data streams received from other households in the example system 100. The example viewing activity analyzer 132 considers any uncertainties in the first data stream 128 and/or the second data stream 130 by calculating the viewing metrics using one or more algorithms that account for probabilities with respect to whether or not the panelist(s) 104, 118 are watching television, what program each panelist 104, 118 is watching, etc.
The example viewing activity analyzer 132 generates one or more viewing metric outputs 134. The viewing metric output(s) 134 can include ratings and/or shares for one or more of the programs 112a-112n. In some examples, the viewing metric output(s) 134 can include analysis results with respect to viewing activity of a population subgroup of interest, such as a particular demographic subgroup (e.g., an age group). The viewing metric output(s) 134 can be presented via one or more output devices 136, such as a display screen of a personal computing device (e.g., associated with the processor 126).
FIG. 2 is a block diagram of an example implementation of the viewing activity analyzer 132 of FIG. 1. As illustrated in FIG. 2, the example viewing activity analyzer 132 includes a data collector 200. The example data collector 200 receives one or more of the data streams 128, 130 from the panel meters 108, 122. As disclosed above, the data streams 128, 130 include data such as date, time, and/or duration that the television(s) 106, 120 were turned on; the channel(s) 110a-110n to which the television(s) 106, 120 were tuned; the programs 112a-112n broadcast by the channel(s) 110a-110n; the respective demographics 114, 124 of the panelists 104, 118, etc. In some examples, the data collector 200 filters and/or formats the data streams 128, 130 for processing by the viewing activity analyzer 132. The data streams 128, 130 received by the data collector 200 are stored in a database 202 of the example viewing activity analyzer 132 of FIG. 2.
The example viewing activity analyzer 132 includes a sampling weight assigner 204. The example sampling weight assigner 204 assigns a sampling weight 205 to each panelist 104, 118 based on, for example, the respective demographics 114, 124 of each panelist 104, 118. The sampling weight(s) 205 assigned by the example weight assigner 204 to each panelist 104, 118 is indicative of a number of other television viewers that each panelist 104, 118 represents based on, for example, one or more similar demographics 114, 124 (e.g., age, gender, socioeconomic status). For example, if the sampling weight assigner 204 assigns a sampling weight 205 having a value of ten to the first panelist 104, the first panelist 104 represents ten people sharing similar demographics 114 as the first panelist 104.
In some examples, the sampling weight 205 is based on whether the panel meter(s) 108, 122 were working properly during a time period in which the data of the data stream(s) 128, 130 was collected. For example, if a known power outage affected the first household 102 and, thus, the ability of the first panelist 104 to watch the first television 106 and the first panel meter 108 to collect data, the example sampling weight assigner 204 can adjust the sampling weight 205 assigned to the first panelist 104 to reflect a number of people who were affected by the power outage.
In the example of FIG. 2, the sampling weight(s) 205 assigned to the panelist(s) 104, 118 can be based on one or more sampling weight rule(s) 206 stored in the database 202 of FIG. 2. The sampling weight rules 206 can include one or more rules with respect to a value of the sampling weight(s) 205 to be assigned to each panelist 104, 118 based on demographic factors such as age, gender, household size, etc. The example sampling weight assigner 204 of FIG. 2 compares the demographic data 114, 124 in the data streams 128, 130 to the sampling weight rule(s) 206 to determine the sampling weight(s) 205 to assign to the panelist(s) 104, 118.
The example viewing activity analyzer 132 of FIG. 2 includes a probability identifier 208. The example probability identifier 208 analyzes the first and second data streams 128, 130 to identify any uncertainties in the data streams 128, 130. For example, the probability identifier 208 can identify missing data in the first and/or second data streams 128, 130 with respect to, for example, data regarding whether or not the panelist(s) 104, 118 where watching the television(s) 106, 120, what program(s) 112a-112n the panelist(s) 104, 118 were watching, etc. The probability identifier 208 can identify inconsistencies in the first and/or second data streams 128 such as data corresponding to one or more program(s) 112a-112n that did not air during the time period for which the data was collected. The probability identifier 208 can identify potential co-viewing activity based on, for example, a number of panelists 104, 118 associated with each household 102, 116.
In other examples, the probability identifier 208 does not identify any uncertainties in the first and/or second data streams 128, 130. For example, the data stream(s) 128, 130 can include data with respect to the television program(s) 110a-112n that the panelist(s) 104, 118 were watching that has not been affected by, for example, any technical errors in the data collection.
In some examples, the probability identifier 208 assigns one or more viewing probabilities 209 to the panelist(s) 104, 118 based on the uncertainties identified in the data stream(s) 128, 130 with respect to, for example, whether or not the panelist(s) 104, 118 are watching television, what program(s) 112a-112n the panelist(s) 104, 118 could have watched, etc. The example probability identifier 208 assigns the probabilities 209 based on one or more probability rules 207 stored in the example database 202 of FIG. 2. The probability rules 207 can include predefined rules with respect to probability values to be assigned to the panelists 104, 118 based on, for example, the number of programs 112a-112n that the panelist(s) 104, 118 could be watching at a given time, the sampling weights 205 assigned to the panelist(s) 104, 118, historical viewing data for the respective panelist(s) 104, 118 stored in the database 202, etc.
Table 1, below, is an example table generated by the example probability identifier 208 of FIG. 2. Table 1 includes probabilistic viewing activity for a plurality of panelists (e.g., the panelists 104, 118 of FIG. 1) whose viewing data is received by the data collector 200 of the example viewing activity analyzer 132. Table 1 includes the probabilistic viewing activity with respect to a first program 112a (P112a), a second program 112b (P112b), and a third first program 112c (P112c). Table 1 also includes probabilities with respect to whether or not the panelists are watching television (P0).







TABLE 1







Viewing Activity Probabilities














Age (e.g.,
Sampling







demographics
Weights


Panelist
114, 124)
(205)
P0
P112a
P112b
P112c
















A (e.g.,
Young
10
0.5
.5
0
0


panelist 104)


B (e.g.,
Young
60
0
.33
.33
.33


panelist 118)


C
Young
20
1
0
0
0


D
Middle
80
.1
.2
.3
.4


E
Middle
40
0
0
1
0


F
Middle
70
0
.3
.5
.2


G
Old
90
.25
.25
.25
.25


H
Old
30
.4
.3
.2
.1


I
Old
50
.1
.7
0
.2









As illustrated above, the example Table 1 includes panelist identifiers (e.g., letters A-H), associated demographics (e.g., age), and respective sampling weights 205 assigned to the panelists (e.g., by the sampling weight assigner 204 of the viewing activity analyzer 132). In example Table 1, the values in the third column P0 represent a probability that a respective panelist is not watching television, the values in the fourth column P112a represent a probability that a panelist is watching the first program 112a, the values in the fifth column P112b represent a probability that a panelist is watching the second program 112b, and the value in the sixth column P112c represent a probability that a panelist is watching the third program 112c. 
For example, referring to Table 1, the probability identifier 208 determines based on the first data stream 128 that Panelist A (e.g., the first panelist 104 of FIG. 1) is either not watching television with a 50% probability or watching the first program 112a with a 50% probability.
As another example, the probability identifier 208 determines based on, for example, the second data stream 130, that Panelist B (e.g., the second panelist 118 of FIG. 1) is watching television. However, the probability identifier 208 is unable to determine which program 112a, 112b, 112c Panelist B is watching based on the second data stream 130. Accordingly, the probability identifier 208 assigns equal probabilities to Panelist B with respect to the first, second, and third programs 112a, 112b, 112c. As another example, the probability identifier 208 can determine that Panelist E is watching the second program 112b based on a data stream received by the data collector 200 for Panelist E. Accordingly, the probability identifier 208 assigns Panelist E a probability of “1” based on the data indicating that Panelist E is watching the first program 112a. Thus, as disclosed above, the example probability identifier 208 analyzes the data streams (e.g., the data streams 128, 130) and assigns probabilities 209 with respect to viewing activity based on the data, including any uncertainties in the data.
The example viewing activity analyzer 132 of FIG. 2 includes a ratings calculator 210. The example ratings calculator 210 calculates one or more ratings 211 for one or more of the programs 112a, 112b, 112c based on the data in the data streams (e.g., the data streams 128, 130) in view of the probabilities 209 determined by the probability identifier 208 (e.g., as provided in Table 1). In the example of FIG. 2, the ratings calculator 210 also determines a null rating 211 representative of a percent of panelists not watching television (e.g., P0). The example ratings calculator 210 of FIG. 2 employs a plurality of algorithms that account for the sampling weights 205 assigned to the respective panelists by the sampling weight assigner 204 and the probabilities 209 assigned by the probability identifier 208.
For example, the ratings calculator 210 can apply the following equations to determine the expected ratings 211 for the first, second, and third programs 112a, 112b, 112c and the percent of televisions not tuned to any of the programs 112a, 112b, 112c: 
Where pk,i is a probability that the kth panelist is watching the ith program, wk is a sampling weight associated with the kth panelist, and n is the number of panelists,




  
    
      
        
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Thus, expected ratings, variance, and covariance calculations are summed across the number of panelists n (e.g., the Panelists A-H of Table 1, above). In some examples, the ratings calculator 210 utilizes a normalized sampling weight or weighted average vk for the sampling weights 205 associated with the panelists, where




  
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Equations 1-3 above can be modified to include the normalized weight vk as follows:

E[Ri]=Σk=1nvkpk,i  (4)

Var[Ri]=Σk=1nvk2(1−pk,i)pk,i  (5)

Cov[Ri,Rj]=−Σk=1nvk2pk,ipk,j  (6)

In Equation (4), above, the expected ratings 211 for the ith program (e.g., one of programs 112a, 112b, 112c) are determined by summing the weighted average vk by the probability that the panelists (and, thus, the number of people each panelist represents) are watching the ith program.
In Equation (5), above, the variance calculation accounts for a probability that, for example, Panelist A (e.g., the first panelist 104 of FIG. 1) is not watching television and a probability that Panelist A is watching the ith program (e.g., the first program 112a). Thus, Equation (5) accounts for uncertainties in the first data stream 128 with respect to whether or not the first panelist 104 is watching the first program 112a (e.g., pk,i) or is not watching television (e.g., (1−pk,i)) by considering both probabilities.
Equation (5) also considers the sampling weight 205 assigned to Panelist A (e.g., the first panelist 104) and, accordingly, a portion of the population represented by the Panelist A. For example, as indicated in example Table 1, above, the Panelist A is assigned a weight of ten. Thus, Panelist A represents ten individuals sharing, for example, a similar age demographic as Panelist A. As such, if there is a 20% probability that Panelist A is watching the first program 112a, then the ten people represented by the Panelist A are also considered to be watching the first program 112a with a probability of 20%. Thus, Equation (5) considers the probability that Panelist A is watching television and/or is watching one of the programs 112a, 112b, 112c as well as the portion of the population represented by the first panelist 104. In Equation (5), the variance is summed across the panelists to account for the fact that different panelists are associated with different probabilities of viewing a program and/or different probabilities with respect to not viewing television.
Referring to Table 1 above including the probabilities 209 of television viewership activity, the example ratings calculator 210 calculates the ratings 211 for the first program 112a, the second program 112b, and the third program 112c using Equations (1) or (4). The ratings calculator 210 also calculates a null rating 211 representing a percentage of panelists not watching television. For example, the ratings calculator 210 can calculate the following expected ratings 211 for P0, P112a, P112b, P112c of Table 1 as follows:

E[Ri]=[0.1611 0.2855 0.3274 0.2259]  (7)

Also, the example ratings calculator 210 can calculate a covariance matrix σ2(Ri, Rj) based on the variance equations (e.g., Equations (2) or (5)) and the covariance equations (e.g., Equations (3) or (6)) as follows:




  
    
      
        
          
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                    8
                  
                
                
                  
                    
                      +
                      
                        0
                        .
                        0
                      
                    
                    ⁢
                    2
                    ⁢
                    5
                    ⁢
                    3
                  
                
              
            
            )
          
          .
        
      
    
    
      
        (
        8
        )
      
    
  




The covariance matrix (8) indicates relationships between, for example, the first program 112a and the other programs 112b, 112c. In the example covariance matrix (8), the diagonals of the matrix are computed by the ratings calculator 210 based on the variance (e.g., Equations (2) or (5)) and the off-diagonals of the matrix are computed based on the covariance (e.g., Equations (3) or (6)). In the example covariance matrix (8), the off-diagonals include negative values. The negative values of the off-diagonals in the covariance matrix (8) reflect the fact out of the potential viewing population, more people in the population who are watching one program (e.g., the first program 112a) means that less people in the population are able to watch the other programs (e.g., the second program 112b, the third program 112c). Also, the ratings calculator 210 considers the population that may not be watching television because that population is a part of the total potential viewing population. Thus, the example ratings calculator 210 of FIG. 2 calculates the ratings for the first, second, and third programs 112a, 112b, 112c based the probabilities that the panelists (and, thus, the portion of the population they represent) are viewing television or not viewing television.
The example viewing activity analyzer 132 of FIG. 2 includes a share calculator 212. The share calculator 212 determines share(s) 213, or a percentage of televisions that are in use that are tuned to a certain program. The shares computed by the example share calculator 212 are conditional based on the panelists (e.g., the panelists 104, 118 of FIG. 1) who are watching television. As disclosed above, there may be uncertainties with respect to whether a panelist such as the first panelist 104 and/or the second panelist 118 is watching television. Thus, the number of panelists who watching are television is a random variable. The shares calculator 212 considers the different panelists who may be watching television, as each panelist's sampling weight 205 may differ from another panelist.
The random variables with respect to the number of panelists who are watching television and the different sampling weights 205 associated each panelist can consume extensive resources of a processor (e.g., the processor 126 of FIG. 1) to calculate exact shares values. For example, to calculate the exact shares values, the shares calculator 212 would need to run multiple simulations considering all of the programs 112a-112n the panelists could be watching, with different panelists treated as watching different programs for each simulation. The multiple simulations consume resources of the processor 126, which can increase a time to perform the analysis and decrease efficiency. However, the shares calculator 212 of FIG. 2 increases the efficiency in determining the share(s) 213 by approximating the share(s) 213 as a conditional distribution of ratings. In the example of FIG. 2, the calculation of the share(s) 213 based on the conditional distribution of ratings converges to the exact shares values as the number of panelists considered increases. For a large panel size (e.g., thousands of panelists), the difference between the shares 213 calculated by the shares calculator 212 based on the conditional distribution and the exact shares values (e.g., calculated based on multiple simulations with the panelists watching different programs in each simulation) is substantially negligible.
The example shares calculator 212 of FIG. 2 determines a probability that a panelist is watching a particular program (e.g., the first, second, or third programs 112a, 112b, 112c), on the condition that the panelist is watching television. The shares calculator 212 calculates a share weight 215 for each panelist (e.g., the panelists 104, 118 of FIG. 1) based on a product of the sampling weight 205 assigned to the panelist and a probability that the panelist is not viewing television. The shares calculator 212 calculates a normalized share weight zk based on the sampling weights 205 (e.g., the sampling weights 205 in Table 1) as follows:




  
    
      
        
          z
          k
        
        =
        
          
            
              w
              k
            
            ⁡
            
              (
              
                1
                -
                
                  p
                  
                    k
                    ,
                    0
                  
                
              
              )
            
          
          
            
              Σ
              
                k
                =
                1
              
              n
            
            ⁢
            
              
                w
                k
              
              ⁡
              
                (
                
                  1
                  -
                  
                    p
                    
                      k
                      ,
                      0
                    
                  
                
                )
              
            
          
        
      
    
    
      
        (
        9
        )
      
    
  




Equation (9) adjusts the respective sampling weights 205 assigned to the panelists based on the probabilities pk,0 that the panelists are not watching television. The shares calculator 212 calculates a conditional share probability that if a panelist is watching television, then the panelist is watching the ith program, as follows:




  
    
      
        
          s
          
            k
            ,
            i
          
        
        =
        
          
            p
            
              k
              ,
              i
            
          
          
            1
            -
            
              p
              
                k
                ,
                0
              
            
          
        
      
    
    
      
        (
        10
        )
      
    
  




In the example of FIG. 2, the shares calculator 212 generates a table including share weights 215 for each panelist in Table 1 (above) and conditional probabilities with respect to whether each panelist watching the first, second, or third programs 112a, 112b, 112c Table 2, below, is an example table generated by the shares calculator 212 based on Equations (9) and (10) for the panelists in Table 1:







TABLE 2







Conditional Share Probabilities













Age (e.g.,
Share






demographics
Weights





Panelist
114, 124)
(215)
S1
S2
S3















A (e.g.,
Young
5
1
0
0


panelist 







104)







B (e.g.,
Young
60
.333
.333
.333


panelist 







118)







C
Young
0
N/A
N/A
N/A


D
Middle
72
.222
.333
.444


E
Middle
40
0
1
0


F
Middle
70
.3
.5
.2


G
Old
67.5
.333
.333
.333


H
Old
18
.5
.333
.166


I
Old
45
.777
0
.222









For example, in Table 1, above, Panelist C is assigned a sampling weight 205 of 20 by the example weight assigner 204 of FIG. 2 (e.g., based on demographics associated with Panelist C). However, Panelist C is also assigned a value of 1 with respect to P0, indicating that Panelist C is not watching television. Accordingly, the example shares calculator 212 adjusts the sampling weight 205 assigned to Panelist C such that Panelist C has a share weight 215 of 0 because Panelist C is not watching television. As illustrated in example Table 2, because Panelist C is not watching television, Panelist C does not contribute to the calculation of the shares 213 for the first, second, and/or third programs 112a, 112b, 112c. 
As another example, in Table 1, Panelist A is assigned a 50% probability of not watching television and a 50% probability of watching the first program 112a. Accordingly, the example shares calculator 212 adjusts the share weight 215 assigned to Panelist A in Table 2. Also, the example shares calculator 212 determines a conditional share probability indicating that if Panelist A is watching a program, then Panelist A is watching the first program 112a (e.g., as indicated by the value “1” for S1).
As another example, Table 1 indicates that there is a 10% probability that Panelist D is not watching television. Thus, there is a 90% probability that Panelist D is watching television. The example shares calculator 212 of FIG. 2 adjusts the sampling weight 205 (e.g., 80) assigned to Panelist D to obtain the share weight 215 for Panelist D (e.g., 80*0.9=72). Thus, although for ratings purposes, Panelist D represents 80 people, for purposes of determining shares, Panelist D represents 72 people. As also indicated in Table 1, there is a 20% probability that Panelist D is watching the first program 112a, a 30% probability of watching the second program 112b, and a 40% probability of watching the third program 112c, and, thus, a 90% probability that Panelist D is watching one of the programs 112a, 112b, 112c. The shares calculator 212 calculates, for example, a conditional share probability S1 that Panelist D is watching the first program 112a based on the probability that Panelist D is watching the first program from Table 1 (e.g., 0.2/0.9=0.222). The shares calculator 212 calculates a conditional share probability S2 that Panelist D is watching the second program 112b (e.g., 0.3/0.9=0.333) and a conditional share probability S3 that Panelist D is watching the third program 112b (e.g., 0.4/0.9=0.444). Thus, the conditional share probabilities S1, S2, S3 in Table 2 are based on the condition that a panelist is viewing television.
The examples shares calculator 212 of FIG. 2 computes the expected shares for the ith program (e.g., first, second, and/or third programs 112a, 112b, 112c), the variance, and covariance based on the data in example Table 2 as follows:

E[Si]=Σk=1nzksk,i  (11)

Var[Si]=Σk=1nzk2(1−sk,i)sk,i  (12)

Cov[Ri,Rj]=−Σk=1nzk2sk,isk,j  (13)

In some examples, if the ratings for the ith program (e.g., first, second, and/or third programs 112a, 112b, 112c) have been calculated (e.g., as disclosed above with respect to Equations (1) or (4)), the shares calculator 212 calculates the expected shares as follows:




  
    
      
        
          E
          ⁡
          
            [
            
              S
              i
            
            ]
          
        
        =
        
          
            E
            ⁡
            
              [
              
                R
                i
              
              ]
            
          
          
            1
            -
            
              E
              ⁡
              
                [
                
                  R
                  0
                
                ]
              
            
          
        
      
    
    
      
        (
        14
        )
      
    
  




The expected shares E[Si] computed by the example shares calculator 212 represents the condition probability that given that the panelist is watching television, then the panelist and, thus, the persons the panelist represents, is watching the ith program (e.g., first, second, or third programs 112a, 112b, 112c).
Referring to Table 2 above including the probabilities of viewership activity with respect to the first, second, and/or third programs 112a, 112b, 112c, the example shares calculator 212 calculates the expected shares 213 for the first program 112a, the second program 112b, and the third program 112c using Equations (11) or (14). For example, the shares calculator 212 can calculate the following expected shares 213 for first, second, and/or third programs 112a, 112b, 112c as follows:

E[Si]=[0.3404 0.3907 0.2689]  (15)

Also, the example shares calculator 212 can calculate a covariance matrix σ2(Si, Sj) based on the variance (e.g., Equation (12)) and the covariance (e.g., Equation (13)) for Table 2 as follows:




  
    
      
        
          
            σ
            2
          
          ⁡
          
            (
            
              
                S
                i
              
              ⁢
              
                S
                j
              
            
            )
          
        
        =
        
          (
          
            
              
                
                  
                    0
                    .
                    0
                  
                  ⁢
                  2
                  ⁢
                  9
                  ⁢
                  3
                
              
              
                
                  
                    -
                    
                      0
                      .
                      0
                    
                  
                  ⁢
                  1
                  ⁢
                  4
                  ⁢
                  6
                
              
              
                
                  
                    -
                    
                      0
                      .
                      0
                    
                  
                  ⁢
                  1
                  ⁢
                  4
                  ⁢
                  7
                
              
            
            
              
                
                  
                    -
                    
                      0
                      .
                      0
                    
                  
                  ⁢
                  1
                  ⁢
                  4
                  ⁢
                  6
                
              
              
                
                  
                    0
                    .
                    0
                  
                  ⁢
                  2
                  ⁢
                  9
                  ⁢
                  9
                
              
              
                
                  
                    -
                    
                      0
                      .
                      0
                    
                  
                  ⁢
                  1
                  ⁢
                  5
                  ⁢
                  3
                
              
            
            
              
                
                  
                    -
                    
                      0
                      .
                      0
                    
                  
                  ⁢
                  1
                  ⁢
                  4
                  ⁢
                  7
                
              
              
                
                  
                    -
                    
                      0
                      .
                      0
                    
                  
                  ⁢
                  1
                  ⁢
                  5
                  ⁢
                  3
                
              
              
                
                  
                    0
                    .
                    0
                  
                  ⁢
                  3
                  ⁢
                  0
                  ⁢
                  0
                
              
            
          
          )
        
      
    
    
      
        (
        16
        )
      
    
  




The covariance matrix (16) indicates relationships between, for example, the first program 112a and the other programs 112b, 112c. In the example covariance matrix (16), the diagonals of the matrix (16) are computed by the shares calculator 212 based on the variance (e.g., Equation (12)) and the off-diagonals of the matrix are computed based on the covariance (e.g., Equation (13)). In the example covariance matrix (16), the off-diagonals include negative values. The negative values of the off-diagonals in the covariance matrix (16) reflect the fact out of the population who is viewing television, more people in the population who are watching one program (e.g., the first program 112a) means that less people in the population are watching the other programs (e.g., the second program 112b, the third program 112c). Thus, the example shares calculator 212 of FIG. 2 calculates the shares for the first, second, and third programs 112a, 112b, 112c based the probabilities that the panelists (and, thus, the population the panelists represent) are viewing the television and viewing certain programs.
Thus, the ratings calculator 210 and the shares calculator 212 of the example viewing activity analyzer 132 of FIG. 2 determines ratings and/or shares for one or more of the programs 112a-112n that may be viewed by panelist, such as the first panelist 104 and/or the second panelist 118 of FIG. 1. As disclosed above, each of the panelists 104, 118 is associated with respective demographics 114, 124. The example viewing activity analyzer 132 of FIG. 2 can also calculate the ratings and/or shares for the program(s) 112a-112n based on a subgroup of interest, such as a subgroup associated with a particular demographic (e.g., age, gender).
The example viewing activity analyzer of FIG. 2 includes a subgroup analyzer 214. In some examples, a user of the example processor 126 of FIG. 1 can request that the ratings calculator 210 of the viewing activity analyzer 132 calculate ratings 211 for one or more of the programs 112a-112n for a particular demographic group (e.g., by providing a user input to the processor 126). Additionally or alternatively, the user can request that the shares calculator 212 calculate shares 213 for one or more of the programs 112a-112n for a particular demographic group. The example subgroup analyzer 214 identifies the relevant demographics 114, 124 of the data streams 128, 130 stored in the example database 202 of the viewing activity analyzer 132. The subgroup analyzer 214 provides the relevant demographic data to the ratings calculator 210 and/or the shares calculator 212.
For example, referring to Table 1 above, a user may be interested in ratings 211 and shares 213 for one or more of the programs 112a-112n for just the “young” demographic group. Based on a user input received by the processor 126 directing the viewing activity analyzer 132 to determine the ratings for the “young” demographic group, the example subgroup analyzer 214 identifies the relevant data streams 128, 130 stored in the database 202 corresponding to the demographic group of interest. For example, with respect to the “young” demographic group, the subgroup analyzer 214 identifies the viewing data associated with Panelist A (e.g., the first panelist 104), Panelist B (e.g., the second panelist 118), and Panelist C based on their association with the demographic group of interest. In some examples, the subgroup analyzer 214 scans the data stored in the database 202 to identify the relevant panelist viewing data based on, for example, tags associated with the data stream 128, 130 stored in the database 202.
The example subgroup analyzer 214 provides the relevant viewing data for the demographic group of interest to the ratings calculator 210 and the shares calculator 212. The example ratings calculator 210 of FIG. 2 applies one or more of Equations (1)-(6) above to determine the expected rating(s) 211 for the programs(s) 112a-112n for the selected demographic group. For example, the ratings calculator 210 performs the summations for only the demographic group of interest (e.g., E[Ri]=Σk=1nvkpk,i, where n is the number of panelists in the “young” demographic group). In some examples, the ratings calculator 210 determines normalized weights (e.g., the weight vk) for the demographic group of interest based on the sampling weights 205 assigned to the panelists associated with the demographic group of interest. The rating calculator 210 uses the normalized weights to calculate the expected ratings, variance, and/or covariance for the demographic group of interest.
Similarly, the example shares calculator 212 of FIG. 2 calculates the share(s) 213 for the program(s) 112a-112n using the normalized weights for the demographic group of interest and by summing across the number of panelists in the demographic group of interest to calculate the expected share(s) 213, variance, and/or covariance (e.g., using Equations (9)-(14)). Thus, the example viewing activity analyzer 132 can determine expected ratings and/or shares and respective variance and covariance of the ratings and/or shares for a subgroup of interest.
The example subgroup analyzer 214 can also determine one or more subgroup viewing metrics 217. For example, the subgroup analyzer 214 can determine a probability that a person within a demographic group of interest is watching a particular program 112a-112n (e.g. in response to user input received by the processor 126). For example, a user may be interested in a probability that a person in the “middle” demographic age group of Table 1 is watching the one of the programs 112a, 112b, 112c. In such examples, the example subgroup analyzer 214 of FIG. 2 identifies Panelists D, E, and F as associated with the “middle” age group and generates a vector K including viewing data for Panelists D, E, and F from the respective data streams stored in the database 202. For example, based on the data in the vector K, the subgroup analyzer 214 can determine the probability that any person within the “middle” age group is watching ith program as follows:

Prob[K∈ith program]=1−Πk∈K(1−pk,i)  (17),

where Prob[K∈ith program] is the probability at least one person in the subgroup of interest is watching the ith program and (1−pk,i) is the probability a person in the subgroup is not watching the ith program.

Thus, Equation (17) calculates a product over members of the selected subgroup with respect to the subgroup members watching a program of interest.
For example, referring to Table 1, the probability identifier 208 identified a 20% probability that Panelist D is watching the first program 112a, a 0% probability that Panelist E is watching the first program 112a, and a 30% probability that Panelist F is watching the first program 112a. The subgroup analyzer 214 can determine the probability that one of Panelists D, E, or F are watching the first program 112a as follows:

Prob[“Middle” age group watching first program]=1−(1−0.2)(1−0)(1−0.3)=0.44  (18)

Thus, the subgroup analyzer 214 determines that there is a 44% probability that a panelist (and, thus, the persons the panelist(s) represent) in the “middle” age demographic is watching the first program 112a. Also, subgroup analyzer 214 can determine the variance as follows:

Var[X]=(Πk∈K(1−pk,i))(1−Πk∈K(1−pk,i))  (19)

The example subgroup analyzer 214 of FIG. 2 can also determine for a given program 112a-112n, a percentage of people watching the program who are associated with a certain demographic. In the example of FIG. 2, data regarding the number of panelists in a demographic who are viewing the program 112a-112n of interest and the number of total people viewing the program 112a-112n of interest are random variables. The subgroup analyzer 214 analyzes different probabilistic combinations of groups of panelists (e.g., the panelists in Table 1) who are watching the program 112a-112n of interest and the respective sampling weights 205 assigned to the panelists. In some examples, the subgroup analyzer 214 approximates the percentage of panelists in a demographic group of interest who are watching the program 112a-112n of interest based on a large panel size (e.g., thousands of panelists). For example, for a group of K people, the subgroup analyzer 214 can approximate a proportion of panelists watching program i that belong to the group K as follows:




  
    
      
        
          p
          
            {
            K
            }
          
        
        =
        
          
            
              Σ
              
                k
                ∈
                K
              
            
            ⁢
            
              w
              k
            
            ⁢
            
              p
              
                k
                ,
                i
              
            
          
          
            
              Σ
              
                k
                =
                1
              
              n
            
            ⁢
            
              w
              k
            
            ⁢
            
              p
              
                k
                ,
                i
              
            
          
        
      
    
    
      
        (
        20
        )
      
    
  




In Equation (20), above, the numerator represents the subgroup of interest and the denominator considers all panelists viewing the program of interest (e.g., all demographics). The subgroup analyzer 214 can determine the variance and covariance as follows:




  
    
      
        
          Var
          ⁡
          
            [
            
              p
              
                
                  {
                  K
                  }
                
                ,
                i
              
            
            ]
          
        
        =
        
          
            
              Σ
              
                k
                ∈
                K
              
            
            ⁢
            
              
                w
                k
                2
              
              ⁡
              
                (
                
                  1
                  -
                  
                    p
                    
                      k
                      ,
                      i
                    
                  
                
                )
              
            
            ⁢
            
              p
              
                k
                ,
                i
              
            
          
          
            
              (
              
                
                  Σ
                  
                    k
                    =
                    1
                  
                  n
                
                ⁢
                
                  w
                  k
                
                ⁢
                
                  p
                  
                    k
                    ,
                    i
                  
                
              
              )
            
            2
          
        
      
    
    
      
        (
        21
        )
      
    
  
  
    
      
        
          Cov
          ⁡
          
            [
            
              
                p
                
                  
                    {
                    K
                    }
                  
                  ,
                  i
                
              
              ,
              
                p
                
                  
                    {
                    K
                    }
                  
                  ,
                  j
                
              
            
            ]
          
        
        =
        
          -
          
            
              
                Σ
                
                  k
                  ∈
                  K
                
              
              ⁢
              
                w
                k
                2
              
              ⁢
              
                p
                
                  k
                  ,
                  i
                
              
              ⁢
              
                p
                
                  k
                  ,
                  j
                
              
            
            
              
                (
                
                  
                    Σ
                    
                      k
                      =
                      1
                    
                    n
                  
                  ⁢
                  
                    w
                    k
                  
                  ⁢
                  
                    p
                    
                      k
                      ,
                      i
                    
                  
                
                )
              
              ⁢
              
                (
                
                  
                    Σ
                    
                      k
                      =
                      1
                    
                    n
                  
                  ⁢
                  
                    w
                    k
                  
                  ⁢
                  
                    p
                    
                      k
                      ,
                      j
                    
                  
                
                )
              
            
          
        
      
    
    
      
        (
        22
        )
      
    
  




The covariance determined by Equation (22) can be used to analyze viewing activity for different programs 112a-112n across the subgroup of interest. For example, the covariance can be analyzed with respect to a proportion of viewers belonging to a subgroup across two different programs 112a-112n. 
The example viewing activity analyzer 132 can calculate the ratings 211, the shares 213, and/or the subgroup viewing metrics 217 at the household level in addition or as an alternative to determining viewing metrics at the panelist level or demographic group level. For example, the sampling weight assigner 204 can assign sampling weights 205 to the first household 102 and/or the second household 116 based on, for example, household size. Based on a user request to calculate, for example, ratings 211 and/or shares 213 at the household level, the subgroup analyzer 214 can identify and/or format the viewing data of the data streams 128, 130 by household. As an example, the ratings calculator 210 can determine the ratings 211 based on a probability that any member of the household (e.g., the first household 102) is watching television.
Thus, the example viewing activity analyzer 132 can determine different viewing activity metrics such as ratings 211 and/or shares 213 despite probabilities or uncertainties in the data streams (e.g., the data streams 128, 130 of FIG. 1) received from the panel meters (e.g., the meters 108, 122). The example viewing activity analyzer 132 can also determine subgroup-specific metrics, including, for example, what program(s) a demographic group is watching and/or what demographic group is watching a certain program. The example viewing activity analyzer 132 includes a communicator 216. The communicator 216 outputs one or more of the ratings 211, shares 213, or subgroup metrics (e.g., the viewing metric output(s) 134 of FIG. 1) for display via, for example, the output device 136.
While an example manner of implementing the viewing activity analyzer 132 is illustrated in FIGS. 1-2, one or more of the elements, processes and/or devices illustrated in FIGS. 1-2 may be combined, divided, re-arranged, omitted, eliminated and/or implemented in any other way. Further, the example data collector 200, the example database 202, the example sampling weight assigner 204, the example probability identifier 208, the example ratings calculator 210, the example shares calculator 212, the example subgroup analyzer 214, the example communicator 216 and/or, more generally, the example viewing activity analyzer of FIGS. 1-2 may be implemented by hardware, software, firmware and/or any combination of hardware, software and/or firmware. Thus, for example, any of the example data collector 200, the example database 202, the example sampling weight assigner 204, the example probability identifier 208, the example ratings calculator 210, the example shares calculator 212, the example subgroup analyzer 214, the example communicator 216 and/or, more generally, the example viewing activity analyzer of FIGS. 1-2 could be implemented by one or more analog or digital circuit(s), logic circuits, programmable processor(s), application specific integrated circuit(s) (ASIC(s)), programmable logic device(s) (PLD(s)) and/or field programmable logic device(s) (FPLD(s)). When reading any of the apparatus or system claims of this patent to cover a purely software and/or firmware implementation, at least one of the example data collector 200, the example database 202, the example sampling weight assigner 204, the example probability identifier 208, the example ratings calculator 210, the example shares calculator 212, the example subgroup analyzer 214, the example communicator 216 and/or, more generally, the example viewing activity analyzer of FIGS. 1-2 is/are hereby expressly defined to include a tangible computer readable storage device or storage disk such as a memory, a digital versatile disk (DVD), a compact disk (CD), a Blu-ray disk, etc. storing the software and/or firmware. Further still, the example data collector 200, the example database 202, the example sampling weight assigner 204, the example probability identifier 208, the example ratings calculator 210, the example shares calculator 212, the example subgroup analyzer 214, the example communicator 216 and/or, more generally, the example viewing activity analyzer of FIGS. 1-2 may include one or more elements, processes and/or devices in addition to, or instead of, those illustrated in FIGS. 1-2, and/or may include more than one of any or all of the illustrated elements, processes and devices.
A flowchart representative of example machine readable instructions for implementing the example viewing activity analyzer 132 of FIGS. 1-2 is shown in FIG. 3. In this example, the machine readable instructions comprise a program for execution by a processor such as the processor 126 of FIG. 1 and shown in the example processor platform 400 discussed below in connection with FIG. 4. The program may be embodied in software stored on a tangible computer readable storage medium such as a CD-ROM, a floppy disk, a hard drive, a digital versatile disk (DVD), a Blu-ray disk, or a memory associated with the processor 126, but the entire program and/or parts thereof could alternatively be executed by a device other than the processor 126 and/or embodied in firmware or dedicated hardware. Further, although the example program is described with reference to the flowchart illustrated in FIG. 3, many other methods of implementing the example viewing activity analyzer 132 of FIGS. 1-2 may alternatively be used. For example, the order of execution of the blocks may be changed, and/or some of the blocks described may be changed, eliminated, or combined.
As mentioned above, the example process of FIG. 3 may be implemented using coded instructions (e.g., computer and/or machine readable instructions) stored on a tangible computer readable storage medium such as a hard disk drive, a flash memory, a read-only memory (ROM), a compact disk (CD), a digital versatile disk (DVD), a cache, a random-access memory (RAM) and/or any other storage device or storage disk in which information is stored for any duration (e.g., for extended time periods, permanently, for brief instances, for temporarily buffering, and/or for caching of the information). As used herein, the term “tangible computer readable storage medium” is expressly defined to include any type of computer readable storage device and/or storage disk and to exclude propagating signals and to exclude transmission media. As used herein, “tangible computer readable storage medium” and “tangible machine readable storage medium” are used interchangeably. Additionally or alternatively, the example process of FIG. 3 may be implemented using coded instructions (e.g., computer and/or machine readable instructions) stored on a non-transitory computer and/or machine readable medium such as a hard disk drive, a flash memory, a read-only memory, a compact disk, a digital versatile disk, a cache, a random-access memory and/or any other storage device or storage disk in which information is stored for any duration (e.g., for extended time periods, permanently, for brief instances, for temporarily buffering, and/or for caching of the information). As used herein, the term non-transitory computer readable medium is expressly defined to include any type of computer readable storage device and/or storage disk and to exclude propagating signals and to exclude transmission media. As used herein, when the phrase “at least” is used as the transition term in a preamble of a claim, it is open-ended in the same manner as the term “comprising” is open ended.
The program 300 of FIG. 3 begins at block 302 with the data collector 200 of the example viewing activity analyzer 132 of FIG. 2 accessing one or more data streams such as the first data stream 128 and/or the second data stream 130 of FIG. 1 from the panel meter(s) 108, 122 associated with televisions 106, 120 in one or more households 102, 116 (block 302). The data stream(s) 128, 132 include television viewing data with respect to, for example, a program 112a-112n broadcast by the television(s) 106, 120 and viewed by the panelists 104, 118. The data can be stored in the example database 202 of the example viewing activity analyzer of FIG. 2.
The program of FIG. 3 includes the example sampling weight assigner 204 of FIG. 2 assigning sampling weight(s) 205 to the panelist(s) 104, 118 (block 304). The sampling weight assigner 204 can assign the sampling weight(s) 205 based on, for example, one or more demographics 114, 124 associated with the panelist(s) 104, 118, such as age and/or gender. In some examples, the sampling weight assigner 204 assigns sampling weight(s) 205 to the household(s) 102, 116 from which the data stream(s) 218, 130 are received based on, for example, household size. The sampling weight assigner 204 can assign the sampling weight(s) 205 based on one or more sampling weight rule(s) 206 stored in the example database 202 of the viewing activity analyzer 132 of FIG. 2.
The program of FIG. 3 includes the probability identifier 208 determining viewing probabilities 209 for, for example, the panelist(s) 104, 116 associated with data stream(s) 128, 130 (block 306). The probability identifier 208 identifies uncertainties in the data stream(s) 128, 130 with respect to, for example, whether a panelist is watching television, what program 112a-112n the panelist is watching, etc. In some examples, the uncertainties are due to, for example, potential co-viewing activity between two or more members of a household. In other examples, the uncertainties are due to, for example, a technical error in the collection of the viewing data by the panel meter(s) 108, 122. The probability identifier 208 can determine the viewing probabilities 209 with respect to whether or not a panelist watched television and/or what program(s) 112a-112n the panelist could have watched based on one or more probability rule(s) 207 stored in the example database 202 of FIG. 2. In some examples, the probability identifier 208 identifies the probabilities 209 with respect to, for example, whether or not any member of a household is watching television.
The program of FIG. 3 includes the example ratings calculator 210 of FIG. 2 calculating expected ratings 211 for one or more programs 112a-112n (block 308). In some examples, the ratings calculator 210 uses one or more algorithms to calculate the ratings 211, such as Equations (1) or (4) disclosed above. In determining the ratings 211, the ratings calculator 210 accounts for the probabilities 209 with respect to whether or not the panelist(s) 104, 118 are watching television, what program(s) 112a-112n the panelist(s) 104, 118 are watching, etc. In some examples, the ratings calculator 210 calculates the variance (e.g., using Equations (2), (5)) and/or covariance (e.g., using Equations (3), (6)) with respect to program viewing activity to analyze viewership behavior between, for example, two or more programs 112a-112n (e.g., as reflected in the example covariance matrix (8)). In some examples, the ratings calculator 210 calculates a null rating 211 indicative of a percentage of panelists who are not watching any program.
In some examples of the program of FIG. 3, the shares calculator 212 of FIG. 2 additionally or alternatively calculates the expected share(s) 213 for the program(s) 112a-112n (e.g., using Equation (11) disclosed above) (block 308). For example, to calculate the share(s) 213, the example shares calculator 212 adjusts the sampling weight(s) 205 assigned to the panelist(s) 104, 118 to determine share weight(s) 215 representative of television viewing behavior by the panelist(s) 104, 118 (e.g., based on probabilities 209 indicating that the panelist(s) 104, 118 may or may not be watching television). The example shares calculator 212 calculates the shares 213 based on the share weights 215 and conditional probabilities that the panelist(s) are watching a particular program 112a-112n, if the panelist(s) are watching television (e.g., determined based on the probabilities 209 with respect to program viewing probabilities). In some examples, the shares calculator 212 calculates the variance (e.g., using Equation (12)) and/or covariance (e.g., using Equation (13)) with respect to program viewing activity to analyze viewing activity between, for example, two or more programs 112a-112n (e.g., as reflected in the example covariance matrix (16)).
The example of FIG. 3 includes a determination as to whether the example subgroup analyzer 214 of FIG. 2 is to calculate one or more subgroup viewing metrics 217 (block 310). In some examples, the subgroup analyzer 214 calculates the subgroup viewing metric(s) 217 based on one or more user inputs received via the processor 126 of FIG. 1 that instructs viewing metrics such as ratings 211 and/or shares 213 to be calculated for one or more demographic groups of interest (e.g., an age group, an ethnic group, a gender group).
The subgroup analyzer 214 identifies viewing data for the subgroup of interest based on the data streams 128, 130 stored in the database 202 of FIG. 2 (block 312). In some examples, the subgroup analyzer 214 identifies the relevant viewing data for panelists in the subgroup of interest (e.g., the panelists 104, 118 of FIG. 1) based on one or more tags identify the demographics 114, 124 associated with the panelists.
The example of FIG. 3 includes calculating the one or more subgroup viewing metrics 217 (block 314). In some examples, the subgroup analyzer 214 instructs the ratings calculator 210 to calculate ratings 211 for one or more programs 112a-112n for the subgroup of interest. In some examples, the subgroup analyzer 214 instructs the shares calculator 212 to calculate shares 213 for one or more programs 112a-110n for the subgroup of interest. In such examples, the ratings calculator 210 calculates the ratings 211 (and, in some examples, the variance and covariance) substantially as disclosed above (e.g., at block 308) for the subgroup of interest. Also in some such examples, the shares calculator 212 calculates the shares 213 and, in some examples, the variance and covariance) substantially as disclosed above (e.g., at block 308) for the subgroup of interest.
In some examples, the subgroup analyzer 214 calculates subgroup viewing metrics 217 with respect to, for example, a probability that a subgroup of interest is watching one or more of the programs 112a-112n. For example, the subgroup analyzer 214 uses Equation (17), disclosed above, to determine a probability that any person within a demographic group of interest is watching one of the programs 112a-112n. In some examples, the subgroup analyzer 214 determines a subgroup that is watching a particular program 112a-112n. For example, the subgroup analyzer 214 uses Equation (20), disclosed above, to approximate a proportion of panelists watching one of the programs 112a-112n that belong to a subgroup of interest (e.g., a demographic group of interest).
If a decision is made not to calculate viewing metrics for a subgroup (e.g., at block 310), the example program 300 ends. Also, if there are no further subgroup viewing metrics 217 to calculate (e.g., based on user input(s) received at the processor 126), the example program 300 ends.
FIG. 4 is a block diagram of an example processor platform 400 capable of executing the instructions of FIG. 3 to implement the data collector 200, the example database 202, the example sampling weight assigner 204, the example probability identifier 208, the example ratings calculator 210, the example shares calculator 212, the example subgroup analyzer 214, the example communicator 216 and/or, more generally, the example viewing activity analyzer of FIGS. 1-2. The processor platform 400 can be, for example, a server, a personal computer, a mobile device (e.g., a cell phone, a smart phone, a tablet such as an iPadTM), a personal digital assistant (PDA), an Internet appliance, a set top box, or any other type of computing device.
The processor platform 400 of the illustrated example includes the processor 126. The processor 126 of the illustrated example is hardware. For example, the processor 126 can be implemented by one or more integrated circuits, logic circuits, microprocessors or controllers from any desired family or manufacturer.
The processor 126 of the illustrated example includes a local memory 413 (e.g., a cache). The processor 126 of the illustrated example is in communication with a main memory including a volatile memory 414 and a non-volatile memory 416 via a bus 418. The volatile memory 414 may be implemented by Synchronous Dynamic Random Access Memory (SDRAM), Dynamic Random Access Memory (DRAM), RAMBUS Dynamic Random Access Memory (RDRAM) and/or any other type of random access memory device. The non-volatile memory 416 may be implemented by flash memory and/or any other desired type of memory device. Access to the main memory 414, 416 is controlled by a memory controller.
The processor platform 400 of the illustrated example also includes an interface circuit 420. The interface circuit 420 may be implemented by any type of interface standard, such as an Ethernet interface, a universal serial bus (USB), and/or a PCI express interface.
In the illustrated example, one or more input devices 422 are connected to the interface circuit 420. The input device(s) 422 permit(s) a user to enter data and commands into the processor 126. The input device(s) can be implemented by, for example, an audio sensor, a microphone, a camera (still or video), a keyboard, a button, a mouse, a touchscreen, a track-pad, a trackball, isopoint and/or a voice recognition system.
One or more output devices 136, 424 are also connected to the interface circuit 420 of the illustrated example. The output devices 136, 424 can be implemented, for example, by display devices (e.g., a light emitting diode (LED), an organic light emitting diode (OLED), a liquid crystal display, a cathode ray tube display (CRT), a touchscreen, a tactile output device, a printer and/or speakers). The interface circuit 420 of the illustrated example, thus, typically includes a graphics driver card, a graphics driver chip or a graphics driver processor.
The interface circuit 420 of the illustrated example also includes a communication device such as a transmitter, a receiver, a transceiver, a modem and/or network interface card to facilitate exchange of data with external machines (e.g., computing devices of any kind) via a network 426 (e.g., an Ethernet connection, a digital subscriber line (DSL), a telephone line, coaxial cable, a cellular telephone system, etc.).
The processor platform 400 of the illustrated example also includes one or more mass storage devices 428 for storing software and/or data. Examples of such mass storage devices 428 include floppy disk drives, hard drive disks, compact disk drives, Blu-ray disk drives, RAID systems, and digital versatile disk (DVD) drives.
Coded instructions 432 to implement the instructions of FIG. 3 may be stored in the mass storage device 428, in the volatile memory 1014, in the non-volatile memory 416, and/or on a removable tangible computer readable storage medium such as a CD or DVD.
From the foregoing, it will be appreciated that the above disclosed systems, methods, and apparatus improves the ability to determine viewing metrics such as ratings and/or shares for media such as one or more television programs in view of uncertainties or probabilities in the data from which the viewing metrics are calculated. Examples disclosed herein determines the viewing metrics by accounting for different scenarios with respect to whether a panelist is watching television, what program he or she is watching, etc. and the probabilities that such scenarios will happen. Examples disclosed herein compute expected ratings and/or expected shares and respective variance or covariance thereof despite the probabilities in the viewing data. Thus, examples disclosed herein compute ratings and/or shares that more accurately reflect viewer behavior as compared to ratings and/or shares calculated based on the randomly assigned probability data (e.g., the 0's and 1's).
Examples disclosed herein increase efficiency and reduce processor resources in determining the ratings and/or shares based on the probabilistic data as compared to, for example, repeating probabilistic stimulations thousands of times, by approximating expected ratings and/or shares. Some disclosed examples provide for calculation of subgroup-specific metrics. Disclosed examples provide accurate and efficient analyses of viewing behavior despite uncertainties or probabilities in the viewing data.
Although certain example methods, apparatus and articles of manufacture have been disclosed herein, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers all methods, apparatus and articles of manufacture fairly falling within the scope of the claims of this patent.

## Claims

1. An apparatus comprising:
memory;
machine readable instructions; and
processor circuitry to execute the instructions to:
calculate a first probability for respective ones of a plurality of panelists as having viewed media based on viewing data, the viewing data including incomplete viewing data for one or more of the panelists relative to the media;
identify respective ones of the plurality of panelists as being included in a demographic subgroup based on demographic data for the panelists;
assign a sampling weight to each of the panelists of the plurality of panelists based on the demographic data, wherein the sampling weight assigned to each of the one or more panelists associated with the incomplete viewing data is adjusted relative to the sampling weight assigned to each of the remaining ones of the panelists of the plurality of panelists;
adjust the first probabilities for the respective ones of the plurality of panelists using the sampling weights for the respective ones of the plurality of panelists to generate adjusted first probabilities; and
calculate a second probability of the demographic subgroup having viewed the media based on (a) the adjusted first probabilities for the respective ones of the plurality of panelists in the demographic subgroup and (b) the adjusted first probabilities for each of the panelists in the plurality of panelists.

2. The apparatus of claim 1, wherein the processor circuitry is to execute the instructions to calculate a share indictive of viewership of the media by the demographic subgroup.

3. The apparatus of claim 1, wherein the processor circuitry is to execute the instructions to calculate a rating for the media for the demographic subgroup.

4. The apparatus of claim 3, wherein the processor circuitry is to execute the instructions to:
determine normalized sampling weights for the respective ones of the plurality of panelists in the demographic subgroup; and
calculate the rating based on the normalized sampling weights.

5. The apparatus of claim 1, wherein the demographic subgroup includes a first panelist, a second panelist, and a third panelist, and the processor circuitry is to execute the instructions to calculate a third probability that one of the first panelist, the second panelist, or the third panelist viewed the media based on the respective first probabilities for the first panelist, the second panelist, and the third panelist.

6. The apparatus of claim 1, wherein the demographic subgroup is a first demographic subgroup and the processor circuitry is to execute the instructions to calculate a third probability of a second demographic subgroup having viewed the media based on (c) the adjusted first probabilities for the respective ones of the plurality of panelists in the second demographic subgroup and (d) the adjusted first probabilities for each of the panelists of the plurality of the panelists, the second demographic subgroup different than the first demographic subgroup.

7. The apparatus of claim 1, wherein the media is first media and the processor circuitry is to execute the instructions to:
calculate a third probability for respective ones of the plurality of panelists as having viewed second media based on the viewing data, the viewing data including incomplete viewing data for one or more of the panelists relative to the first media or the second media; and
calculate a fourth probability of the demographic subgroup having viewed the second media based on the third probabilities for the respective ones of the plurality of panelists in the demographic subgroup and the sampling weights for the respective ones of the plurality of panelists in the demographic subgroup.

8. A non-transitory computer-readable medium comprising instructions that, when executed, cause a processor to at least:
calculate a first probability for respective ones of a plurality of panelists as having viewed media based on viewing data, the viewing data including incomplete viewing data for one or more of the panelists relative to the media;
identify respective ones of the plurality of panelists as being included in a demographic subgroup based on demographic data for the panelists;
assign a sampling weight to each of the panelists of the plurality of panelists based on the demographic data, wherein the sampling weight assigned to each of the one or more panelists associated with the incomplete viewing data is adjusted relative to the sampling weight assigned to each of the remaining ones of the panelists of the plurality of panelists; and
adjust the first probabilities for the respective ones of the plurality of panelists using the sampling weights for the respective ones of the plurality of panelists to generate adjusted first probabilities; and
calculate a second probability of the demographic subgroup having viewed the media based on (a) the adjusted first probabilities for the respective ones of the plurality of panelists in the demographic subgroup and (b) the adjusted first probabilities for each of the panelists in the plurality of panelists.

9. The non-transitory computer-readable medium of claim 8, wherein the instructions, when executed, cause the processor to calculate a share indictive of viewership of the media by the demographic subgroup.

10. The non-transitory computer-readable medium of claim 8, wherein the instructions, when executed, cause the processor to execute the instructions to calculate a rating for the media for the demographic subgroup.

11. The non-transitory computer-readable medium of claim 10, wherein the instructions, when executed, cause the processor to:
determine normalized sampling weights for the respective ones of the plurality of panelists in the demographic subgroup; and
calculate the rating based on the normalized sampling weights.

12. The non-transitory computer-readable medium of claim 8, wherein the demographic subgroup includes a first panelist, a second panelist, and a third panelist, and wherein the instructions, when executed, cause the processor to calculate a third probability that one of the first panelist, the second panelist, or the third panelist viewed the media based on the respective first probabilities for the first panelist, the second panelist, and the third panelist.

13. The non-transitory computer-readable medium of claim 8, wherein the demographic subgroup is a first demographic subgroup and the instructions, when executed, cause the processor to calculate a third probability of a second demographic subgroup having viewed the media based on (a) the adjusted first probabilities for the respective ones of the plurality of panelists in the second demographic subgroup and (b) the adjusted first probabilities for each of the panelists of the plurality of the panelists, the second demographic subgroup different than the first demographic subgroup.

14. The non-transitory computer-readable medium of claim 8, wherein the media is first media and the instructions, when executed, cause the processor to:
calculate a third probability for respective ones of the plurality of panelists as having viewed second media based on the viewing data, the viewing data including incomplete viewing data for one or more of the panelists relative to the first media or the second media; and
calculate a fourth probability of the demographic subgroup having viewed the second media based on the third probabilities for the respective ones of the plurality of panelists in the demographic subgroup and the sampling weights for the respective ones of the plurality of panelists in the demographic subgroup.

15. A system comprising:
means for identifying probabilities, the probability identifying means to calculate a first probability for respective ones of a plurality of panelists as having viewed media based on viewing data, the viewing data including incomplete viewing data for one or more of the panelists relative to media;
means for assigning sampling weights, the sampling weight assigning means to:
identify respective ones of the plurality of panelists as being included in a demographic subgroup based on demographic data for the panelists, the viewing data including the demographic data; and
assign a sampling weight to each of the panelists of the plurality of panelists based on the demographic data, wherein the sampling weight assigned to each of the one or more panelists associated with the incomplete viewing data is adjusted relative to the sampling weight assigned to each of the remaining ones of the panelists of the plurality of panelists; and

means for analyzing subgroups, the subgroup analyzing means to:
adjust the first probabilities for the respective ones of the plurality of panelists using the sampling weights for the respective ones of the plurality of panelists to generate adjusted first probabilities; and
calculate a second probability of the demographic subgroup having viewed the media based on (a) the adjusted first probabilities for the respective ones of the plurality of panelists in the demographic subgroup and (b) the adjusted first probabilities for each of the panelists in the plurality of panelists.

16. The system of claim 15, further including means for calculating shares, the share calculating means to calculate a share indictive of viewership of the media by the demographic subgroup.

17. The system of claim 15, further including means for calculating ratings, the rating calculating means to calculate a rating for the media for the demographic subgroup.

18. The system of claim 17, wherein the sampling weight assigning means is to determine normalized sampling weights for the respective ones of the plurality of panelists in the demographic subgroup and the rating calculating means is to calculate the rating based on the normalized sampling weights.

19. The system of claim 15, wherein the demographic subgroup is a first demographic subgroup and the subgroup analyzing means is to calculate a third probability of a second demographic subgroup having viewed the media based on (a) the adjusted first probabilities for the respective ones of the plurality of panelists in the second demographic subgroup and (b) the adjusted first probabilities for each of the panelists of the plurality of the panelists, the second demographic subgroup different than the first demographic subgroup.

20. The system of claim 15, wherein the media is first media, the probability identifying means is to calculate a third probability for respective ones of the plurality of panelists as having viewed second media based on the viewing data, the viewing data including incomplete viewing data for one or more of the panelists relative to the first media or the second media, and the subgroup analyzing means is to calculate a fourth probability of the demographic subgroup having viewed the second media based on the third probabilities for the respective ones of the plurality of panelists in the demographic subgroup and the sampling weights for the respective ones of the plurality of panelists in the demographic subgroup.