In: Statistics and Probability
A publisher reports that 29% of their readers own a laptop. A marketing executive wants to test the claim that the percentage is actually different from the reported percentage. A random sample of 380 found that 25% of the readers owned a laptop. Find the value of the test statistic. Round your answer to two decimal places.
SOLUTION:
From given data,
A publisher reports that 29% of their readers own a laptop. A marketing executive wants to test the claim that the percentage is actually different from the reported percentage. A random sample of 380 found that 25% of the readers owned a laptop.
Let be the proportion of readers own a laptop = 0.25
Let n be the random sample = 380.
Null hypothesis: Ho : p= 0.29
Alternative hypothesis, Ha : p 0.29 (two tail test)
Assume the level of significance, = 0.05.
Compute the test statistic:
= -1.71839
Thus , the test statistics is z = -1.718
The p- value of the test statistic is,
p- value = 2 p(Z > |z| )
= 2 p(Z > 1.718 )
= 2[1-p(z <1.718)]
= 2[1-NORMDIST(1.718)]
= 2[1- 0.95710169]
= 2[0.04289831]
= 0.08579
= 0.08 (Round your answer to two decimal places.)
Since the p-value of the test is greater than the level of significance , do not reject the null hypothesis at 0.05 level of significance.