Methods, apparatus, and articles of manufacture to determine whether audience measurement meters are co-located
Methods, apparatus, systems, and articles of manufacture are disclosed to determine whether audience measurement meters are co-located. An example apparatus is to, based on a difference between a first sampling time of a first entry of a first log and a second sampling time of a corresponding entry of a second log satisfying a first threshold, determine at least one matching instance of at least one first device identifier of the first entry and at least one second device identifier of the corresponding entry. Additionally, the example apparatus is to populate a variable with the at least one matching instance. The example apparatus is also to, based on a metric satisfying a second threshold, cause transmission of an alert indicating that a first meter and a second meter were co-located during generation of the first log and the second log, the metric based on the at least one matching instance.
1 . An audience measurement system to determine whether audience measurement meters were co-located, the audience measurement system comprising:
a processor;
at least one memory having stored thereon computer readable instructions that, when executed by the processor, cause the audience measurement system to be configured to perform a set of operations including:
obtaining a first log from a first meter and a second log from a second meter, each of the first log and the second log including respective entries indicating device identifiers and time stamps corresponding to respective devices that transmit a device detection signal received by the first and second meters at respective time stamps;
identifying multiple matching pairs of entries in both the first log and the second log, wherein each matching pair of entries include one entry from the first log and one entry from the second log that have: (i) a common device identifier, and (ii) respective time stamps that satisfy a synchronization threshold;
determining that the first log and the second log include a set of multiple matching instances, wherein each matching instance of the set of multiple matching instances corresponds to one of the identified multiple matching pairs of entries;
estimating, based on at least some of the time stamps associated with the set of multiple matching instances, a time period during which the first meter and the second meter were co-located; and
in response to estimating the time period during which the first meter and the second meter were co-located, transmitting an alert.
2 . The audience measurement system of claim 1 , wherein the device identifiers include an identifier of at least one radio frequency device detected by the first meter and the second meter.
3 . The audience measurement system of claim 1 , wherein the set of operations further includes identifying the multiple matching pairs of entries in both the first log and the second log by determining that a given pair of entries from the first log and the second log, respectively, have a common given device identifier by executing a string comparison algorithm on at least one first device identifier included in the first log and at least one second device identifier included in the second log.
4 . The audience measurement system of claim 1 , wherein the set of operations further includes identifying the multiple matching pairs of entries in both the first log and the second log by determining that a given pair of entries from the first log and the second log, respectively, have a common given device identifier by executing:
a hidden Markov model on at least one first device identifier included in the first log and at least one second device identifier included in the second log.
5 . The audience measurement system of claim 1 , wherein the set of operations further includes, prior to estimating the time period during which the first meter and the second meter were co-located, determining, based on a count associated with the set of multiple matching instances exceeding a co-location threshold, that the first meter and the second meter were co-located.
6 . The audience measurement system of claim 1 , wherein the synchronization threshold is based on a periodic sampling time at which the first and second meters receive the device detection signal during respective monitoring intervals.
7 . The audience measurement system of claim 1 , wherein the alert is configured to indicate that audience measurement data generated by the first meter and the second meter should be disregarded for at least the time period.
8 . A non-transitory computer readable storage medium storing program instructions that, when executed by a processor, cause performance of a set of operations including:
obtaining a first log from a first meter and a second log from a second meter, each of the first log and the second log including respective entries indicating device identifiers and time stamps corresponding to respective devices that transmit a device detection signal received by the first and second meters at respective time stamps;
identifying multiple matching pairs of entries in both the first log and the second log, wherein each matching pair of entries include one entry from the first log and one entry from the second log that have: (i) a common device identifier, and (ii) respective time stamps that satisfy a synchronization threshold;
determining that the first log and the second log include a set of multiple matching instances, wherein each matching instance of the set of multiple matching instances corresponds to one of the identified multiple matching pairs of entries;
estimating, based on at least some of the time stamps associated with the set of multiple matching instances, a time period during which the first meter and the second meter were co-located; and
in response to estimating the time period during which the first meter and the second meter were co-located, transmitting an alert.
9 . The non-transitory computer readable storage medium of claim 8 , wherein the device identifiers include an identifier of at least one radio frequency device detected by the first meter and the second meter.
10 . The non-transitory computer readable storage medium of claim 8 , wherein the set of operations further includes identifying the multiple matching pairs of entries in both the first log and the second log by determining that a given pair of entries from the first log and the second log, respectively, have a common given device identifier by executing a string comparison algorithm on at least one first device identifier included in the first log and at least one second device identifier included in the second log.
11 . The non-transitory computer readable storage medium of claim 8 , wherein the set of operations further includes identifying the multiple matching pairs of entries in both the first log and the second log by determining that a given pair of entries from the first log and the second log, respectively, have a common given device identifier by executing
a hidden Markov model on at least one first device identifier included in the first log and at least one second device identifier included in the second log.
12 . The non-transitory computer readable storage medium of claim 8 , wherein the set of operations further includes, prior to estimating the time period during which the first meter and the second meter were co-located, determining, based on a count associated with the set of multiple matching instances exceeding a co-location threshold, that the first meter and the second meter were co-located.
13 . The non-transitory computer readable storage medium of claim 8 , wherein the synchronization threshold is based on a periodic sampling time at which the first and second meters receive the device detection signal during respective monitoring intervals.
14 . The non-transitory computer readable storage medium of claim 8 , wherein the alert is configured to indicate that audience measurement data generated by the first meter and the second meter should be disregarded for at least the time period.
15 . A method to determine whether audience measurement meters were co-located, the method comprising:
obtaining a first log from a first meter and a second log from a second meter, each of the first log and the second log including respective entries indicating device identifiers and time stamps corresponding to respective devices that transmit a device detection signal received by the first and second meters at respective time stamps;
identifying multiple matching pairs of entries in both the first log and the second log, wherein each matching pair of entries include one entry from the first log and one entry from the second log that have: (i) a common device identifier, and (ii) respective time stamps that satisfy a synchronization threshold;
determining that the first log and the second log include a set of multiple matching instances, wherein each matching instance of the set of multiple matching instances corresponds to one of the identified multiple matching pairs of entries;
estimating, based on at least some of the time stamps associated with the set of multiple matching instances, a time period during which the first meter and the second meter were co-located; and
in response to estimating the time period during which the first meter and the second meter were co-located, transmitting an alert.
16 . The method of claim 15 , wherein the device identifiers include an identifier of at least one radio frequency device detected by the first meter and the second meter.
17 . The method of claim 15 , further including
identifying the multiple matching pairs of entries in both the first log and the second log by determining that a given pair of entries from the first log and the second log, respectively, have a common given device identifier by executing a string comparison algorithm on at least one first device identifier included in the first log and the at least one second device identifier included in the second log.
18 . The method of claim 15 , further including, prior to estimating the time period during which the first meter and the second meter were co-located, determining, based on a count associated with the set of multiple matching instances exceeding a co-location threshold that the first meter and the second meter were co-located.
19 . The method of claim 15 , further including determining the synchronization threshold based on a periodic sampling time at which the first and second meters receive the device detection signal during respective monitoring intervals.
20 . The method of claim 15 , wherein the alert is configured to indicate that audience measurement data generated by the first meter and the second meter should be disregarded for at least the time period a period.