Multiple meter detection and processing using motion data

1. An apparatus comprising:

at least one memory;

instructions on the apparatus; and

a processor to execute the instructions to:

access media exposure data from at least one of a plurality of portable computing devices;

access motion strings from each of the plurality of portable computing devices, each of said motion strings comprising a successive binary representation of motion over a first period of time;

compare the motion strings in a processor to determine if at least two motion strings match within a predetermined threshold, wherein the comparison of a first motion string of the motion strings for a first portable computing device of the plurality of portable computing devices to respective motion strings of the motion strings for respective ones of the plurality of portable computing devices is based on one of (1) cross-correlation, (2) absolute Manhattan distance, (3) Euclidean distance, and (4) dynamic time warping; and

identify the portable computing devices that produced matching motion strings.

2. The apparatus of claim 1 , wherein the first period of time comprises a plurality of shorter periods of time, and wherein the successive binary representation comprises a series of values representing motion for each of the shorter periods of time.

3. The apparatus of claim 2 , wherein each of the series of values are formed by determining if the gross motion within the shorter period of time exceeded a motion threshold.

4. The apparatus of claim 3 , wherein a binary “1” is generated if the gross motion within the shorter time period meets or exceeds the motion threshold, and a binary “0” is generated if the gross motion within the shorter time period does not meet or exceed the motion threshold.

5. The apparatus of claim 2 , further comprising the comparing a sub-string of each motion strings in a processor to determine if at least two motion sub-strings match within a predetermined threshold.

6. The apparatus of claim 5 , further comprising the comparing to determine if identified devices provided media exposure data.

7. The apparatus of claim 1 , wherein the media exposure data comprises at least one of (i) ancillary codes detected from audio, and (ii) one or more signatures extracted from audio.

8. An apparatus comprising:

at least one memory;

instructions on the apparatus; and

a processor to execute the instructions to:

access media exposure data over a data

network from at least one of a plurality of portable computing devices;

access motion strings over the data network respectively from each of the plurality of portable computing devices, each of said motion strings comprising a successive binary representation of motion over a first period of time;

compare the motion strings to determine if at least two motion strings match within a predetermined threshold, wherein the comparison of a first motion string of the motion strings for a first portable computing device of the plurality of portable computing devices to respective motion strings of the motion strings for respective ones of the plurality of portable computing devices is based on one of (1) cross-correlation, (2) absolute Manhattan distance, (3) Euclidean distance, and (4) dynamic time warping; and

identify the portable computing devices that produced matching motion strings.

9. The apparatus of claim 8 , wherein the first period of time comprises a plurality of shorter periods of time, and wherein the successive binary representation comprises a series of values representing motion for each of the shorter periods of time.

10. The apparatus of claim 9 , wherein each of the series of values are formed by determining if the gross motion within the shorter period of time exceeded a motion threshold.

11. The apparatus of claim 10 , wherein a binary “1” is generated if the gross motion within the shorter time period meets or exceeds the motion threshold, and a binary “0” is generated if the gross motion within the shorter time period does not meet or exceed the motion threshold.

12. The apparatus of claim 9 , further comprising the processor to compare a sub-string of each motion strings in a processor to determine if at least two motion sub-strings match within a predetermined threshold.

13. The apparatus of claim 12 , further comprising the processor to determine if identified devices provided media exposure data.

14. The apparatus of claim 8 , wherein the media exposure data comprises at least one of (i) ancillary codes detected from audio, and (ii) one or more signatures extracted from audio.

15. An apparatus comprising:

at least one memory;

instructions on the apparatus; and

a processor to execute the instructions to:

access media exposure data from a first one of a plurality of portable computing devices;

access segmented accelerometer data from the plurality of portable computing devices, the segmented accelerometer data segmented based on accelerometer data associated with at least one of walking, stopping, running, or sitting;

extract features from the segmented accelerometer data;

form accelerometer classification data for respective ones of the plurality of portable computing devices based on the extracted features;

compare the accelerometer classification data for the first portable computing device to at least one of (i) the accelerometer classification data for respective ones of the plurality of portable computing devices and (ii) stored accelerometer classification data for respective ones of the plurality of portable computing devices, to determine if accelerometer classification data for the first portable computing device is sufficiently similar to a second one of the plurality of portable computing devices, wherein the comparison of the accelerometer classification data for the first portable computing device to the accelerometer classification data for respective ones of the plurality of computing devices is based on one of (1) cross-correlation, (2) absolute Manhattan distance, (3) Euclidean distance, and (4) dynamic time warping; and

identify the first portable computing device and the second portable computing device as being physically carried by a same person when the comparison determines that the accelerometer classification data for the first portable computing device is sufficiently similar to the accelerometer classification data for the second portable computing device; and

identify the first and second portable computing devices as being carried by the same person, the processor to credit the media exposure data for one of the first portable computing device or the second portable computing device, thereby reducing inaccurate media measurement results.

16. The apparatus of claim 15 , wherein the media exposure data comprises at least one of (i) ancillary codes detected from audio, (ii) one or more signatures extracted from audio, (iii) a web page, (iv) application data, and (v) metadata.

17. The apparatus of claim 15 , wherein the plurality of portable computing devices are associated with a group.

18. The apparatus of claim 15 , wherein the accelerometer classification data and stored accelerometer classification data comprise raw accelerometer data processed in one of a time domain and a frequency domain.

19. The apparatus of claim 15 , wherein the accelerometer classification data for the first portable computing device is sufficiently similar when the similarity is above a predetermined threshold.