METHODS AND APPARATUS TO CALCULATE A PROBABILITY OF INDEX CONSISTENCY
Methods, apparatus, systems and articles of manufacture are disclosed to calculate a probability of index consistency. An example method disclosed herein includes selecting a first benchmark audience rating and a first brand user rating, calculating a first ratio of the first benchmark audience rating and a first benchmark audience effective sample size, calculating a second ratio of the first brand user rating and a brand user effective sample size, calculating a standard error based on the first and second ratios and an index based on the first benchmark audience rating and the first brand user rating, and calculating a first consistency value based on the standard error.
1 . A method to calculate an index consistency, comprising:
selecting a first benchmark audience rating and a first brand user rating;
calculating a first ratio of the first benchmark audience rating and a first benchmark audience effective sample size;
calculating a second ratio of the first brand user rating and a brand user effective sample size;
calculating a standard error based on the first and second ratios and an index based on the first benchmark audience rating and the first brand user rating; and
calculating a first consistency value based on the standard error.
2 . A method as defined in claim 1 , further comprising applying a design effect value when calculating the first consistency value, the design effect value based on an interval duration of the first brand user rating.
3 . A method as defined in claim 1 , further comprising applying a design effect value when calculating the first consistency value, the design effect value based on a degree of interlacing between the first brand user rating and the first benchmark audience rating.
4 . A method as defined in claim 1 , wherein the first consistency value is derived from a significance value.
5 . A method as defined in claim 4 , wherein the significance value is associated with a confidence interval.
6 . A method as defined in claim 1 , further comprising selecting a second benchmark audience rating to calculate a second consistency value associated with the first brand user rating.
7 . A method as defined in claim 6 , further comprising selecting a media vehicle based on a comparison between the first and second consistency values.
8 . A method as defined in claim 1 , further comprising generating a heatmap to compare the first consistency value with a plurality of second consistency values associated with second brand user ratings.
9 . A method as defined in claim 1 , further comprising calculating a second consistency value based on a second brand user effective sample size.
10 . An apparatus to calculate an index consistency, comprising:
an audience manager to select a first benchmark audience rating and a first brand user rating;
an error calculation engine to:
calculate a first ratio of the first benchmark audience rating and a first benchmark audience effective sample size; and
calculate a second ratio of the first brand user rating and a brand user effective sample size;
an index engine to calculate a standard error based on the first and second ratios and an index based on the first benchmark audience rating and the first brand user rating; and
a probability manager to calculate a first consistency value based on the standard error.
11 . An apparatus as defined in claim 10 , further comprising a design factor manager to apply a design effect value when calculating the first consistency value, the design effect value based on an interval duration of the first brand user rating.
12 . An apparatus as defined in claim 10 , further comprising a design factor manager to apply a design effect value when calculating the first consistency value, the design effect value based on a degree of interlacing between the first brand user rating and the first benchmark audience rating.
13 . An apparatus as defined in claim 10 , wherein the probability manager is to derive the first consistency value based on a significance value.
14 . An apparatus as defined in claim 13 , wherein the probability manager to to associate the significance value with a confidence interval.
15 . An apparatus as defined in claim 10 , wherein the audience manager is to select a second benchmark audience rating to calculate a second consistency value associated with the first brand user rating.
16 . An apparatus as defined in claim 15 , further comprising a consistency evaluator to select a media vehicle based on a comparison between the first and second consistency values.
17 . An apparatus as defined in claim 10 , further comprising a heat map engine to generate a heat map to compare the first consistency value with a plurality of second consistency values associated with second brand user ratings.
18 . A tangible machine-readable storage medium comprising instructions stored thereon that, when executed, cause a machine to, at least:
select a first benchmark audience rating and a first brand user rating;
calculate a first ratio of the first benchmark audience rating and a first benchmark audience effective sample size;
calculate a second ratio of the first brand user rating and a brand user effective sample size;
calculate a standard error based on the first and second ratios and an index based on the first benchmark audience rating and the first brand user rating; and
calculate a first consistency value based on the standard error.
19 . A machine readable storage medium as defined in claim 18 , wherein the instructions, when executed, cause the machine to apply a design effect value when calculating the first consistency value, the design effect value based on an interval duration of the first brand user rating.
20 . A machine readable storage medium as defined in claim 18 , wherein the instructions, when executed, cause the machine to apply a design effect value when calculating the first consistency value, the design effect value based on a degree of interlacing between the first brand user rating and the first benchmark audience rating.
21 . A machine readable storage medium as defined in claim 18 , wherein the instructions, when executed, cause the machine to derive the first consistency value from a significance value.
22 . A machine readable storage medium as defined in claim 21 , wherein the instructions, when executed, cause the machine to associate the significance value with a confidence interval.
23 . A machine readable storage medium as defined in claim 18 , wherein the instructions, when executed, cause the machine to select a second benchmark audience rating to calculate a second consistency value associated with the first brand user rating.
24 . A machine readable storage medium as defined in claim 23 , wherein the instructions, when executed, cause the machine to select a media vehicle based on a comparison between the first and second consistency values.
25 . A machine readable storage medium as defined in claim 18 , wherein the instructions, when executed, cause the machine to generate a heat map to compare the first consistency value with a plurality of second consistency values associated with second brand user ratings.
26 . A machine readable storage medium as defined in claim 18 , wherein the instructions, when executed, cause the machine to calculate a second consistency value based on a second brand user effective sample size.