Question

A shareholders' group, in lodging a protest, claimed that the mean tenure for a chief executive office (CEO) was at least ten years. A survey of companies reported in the Wall Street Journal found a sample mean tenure of x̄ = 8.66 years for CEOs with a standard deviation of s = 7.39 years.

a. Formulate hypotheses that can be used to challenge the validity of the claim made by the shareholders' group.

H₀ : μ __________ 10 (less than, equal to, less than or equal to, greater than or equal to, not equal to)

Ha : μ __________ 10 (less than, equal to, less than or equal to, greater than or equal to, not equal to)

B. Assume 65 companies were included in the sample. What is the p-value for your hypothesis test? Enter negative value as negative number.

t-value:

Is the p-value: lower than .005, between .005 and .01, between .01 and .025, between .025 and .05. between .05 and .10. between .10 and .20. or greater than .20?

C. at a = 0.01, what is your conclusion? (do we reject the hypothesis, do we/don't we have enough evidence)

Answer 1

Solution :

= 10

= 8.66

s =7.39

n = 65

a ) This is the two tailed test .

The null and alternative hypothesis is ,

H₀ :    = 10

H_a :     10

Test statistic = t

= ( - ) / s / n

= ( 8.66- 10) / 7.39 / 65

= −1.462

Test statistic = t = −1.462

b ) P-value =0.1487

c ) = 0.01  

P-value ≥

0.1487 ≥ 0.01

Do not reject the null hypothesis .

There is insufficient evidence to suggest that