In: Statistics and Probability
25.
Let x be a random variable representing dividend yield of Australian bank stocks. We may assume that x has a normal distribution with σ = 2.6%. A random sample of 17 Australian bank stocks has a sample mean of x = 8.76%. For the entire Australian stock market, the mean dividend yield is μ = 6.5%. Do these data indicate that the dividend yield of all Australian bank stocks is higher than 6.5%? Use α = 0.01. Are the data statistically significant at the given level of significance? Based on your answers, will you reject or fail to reject the null hypothesis?
Select one:
a. The P-value is greater than than the level of significance and so the data are not statistically significant. Thus, we fail to reject the null hypothesis.
b. The P-value is less than than the level of significance and so the data are statistically significant. Thus, we reject the null hypothesis.
c. The P-value is greater than than the level of significance and so the data are statistically significant. Thus, we reject the null hypothesis.
d. The P-value is less than than the level of significance and so the data are not statistically significant. Thus, we reject the null hypothesis.
e. The P-value is less than than the level of significance and so the data are statistically significant. Thus, we fail to reject the null hypothesis.
(E is not the answer)
25)
Solution :
This is the right tailed test .
The null and alternative hypothesis is ,
H0 : = 0.065
Ha : > 0.065
= 0.0876
= 0.065
= 0.026
n = 17
Test statistic = z
= ( - ) / / n
= (0.0876 - 0.065) / 0.026 / 17
= 3.58
Test statistic = 3.58
This is the right tailed test .
P(z > 3.58) = 1 - P(z < 3.58) = 1 - 0.9998 = 0.0002
P-value = 0.0002
= 0.01
P-value <
Reject the null hypothesis .
b. The P-value is less than than the level of significance and so the data are statistically significant. Thus, we reject the null hypothesis.