Question

Consider this hypothesis test situation: A survey organization conducted telephone interviews in December 2008 in which 1,009 randomly selected adults in the United States responded to the following question. At the present time, do you think television commercials are an effective way to promote a new product? Of the 1,009 adults surveyed, 676 responded “yes.” In December 2007, 622 of 1,020 randomly selected adults in the United States had responded “yes” to the same question. Perform a test to determine if the data provide evidence that the proportion of adults in the United States who would respond “yes” to the question changed from December 2007 to December 2008. If a StatKey randomization test of the difference of proportions is used to perform this test, what is the size of the P-value ? Group of answer choices

The P-value is above 10%

The P-value is between 5% and 10%

The P-value is between 1% and 5%

The P-value is less than 1%

Answer 1

Given:

n1=1009, X1=676, n2=1020, X2=622,

Hypothesis:

Ho: P1 = P2

Ha: P1 P2

Calculation:

Q = 1-P = 1-0.64 = 0.36

Test statistic:

P-value = 0.0048         ........................Using standard Normal table

ANSWER: D

d. The P-value is less than 1%