10.4: Inferences About the Difference Between Two PopulationProportions
In a test of the quality of two television commercials, eachcommercial was shown in a separate test area six times over aone-week period. The following week a telephone survey wasconducted to identify individuals who had seen the commercials.Those individuals were asked to state the primary message in thecommercials. The following results were recorded.
| Commercial A | Commercial B |
| Number Who Saw Commercial | 155 | 204 |
| Number Who Recalled Message | 64 | 63 |
Use and test the hypothesis that there is no difference in therecall proportions for the two commercials.
Formulate the null and the alternative hypotheses.
- Select your answer -greater than or equal to 0greater than0less than or equal to 0less than 0equal to 0not equal to 0Item1
- Select your answer -greater than or equal to 0greater than0less than or equal to 0less than 0equal to 0not equal to 0Item2
What is the value of the test statistic (to 2 decimals)?
What is the -value (to 4 decimals)?
Does there appear to be a difference in recall proportions forthe two commercials?
- Select your answer -NoYesItem 5
Compute a confidence interval for the difference between therecall proportions for the two populations (to 4 decimals).
( , )
It appears that - Select your answer -Commercial ACommercialBneither commercial item 8 has a better recall rate.
Use and test thehypothesis that there is no difference in the recall proportionsfor the two commercials.
Formulate the null andthe alternative hypotheses.
- Select your answer-greater than or equal to 0greater than 0less than or equal to0less than 0equal to 0not equal to 0
- Select your answer-greater than or equal to 0greater than 0less than or equal to0less than 0equal to 0not equal to 0
What is the value ofthe test statistic (to 2 decimals)?
What is the -value (to4 decimals)?
Does there appear tobe a difference in recall proportions for the two commercials?
- Select your answer-NoYes
Compute 95 % aconfidence interval for the difference between the recallproportions for the two populations (to 4 decimals).
( ______, ______)
It appears that -Select your answer -
Commercial A
Commercial B
neither Commercial
Commercial none
