In: Statistics and Probability
The dean of a university estimates that the mean number of classroom hours per week for full-time faculty is 11.0. As a member of the student council, you want to test this claim. A random sample of the number of classroom hours for eight full-time faculty for one week is shown in the table below. At alphaequals0.05, can you reject the dean's claim? Complete parts (a) through (d) below. Assume the population is normally distributed. 11.2 9.8 13.2 8.1 5.4 9.5 14.5 9.6
(a) Write the claim mathematically and identify Upper H 0 and Upper H Subscript a.
Which of the following correctly states Upper H 0 and Upper H Subscript a? A.
Upper H 0: muequals11.0 Upper H Subscript a: munot equals11.0
B. Upper H 0: muless than or equals11.0 Upper H Subscript a: mugreater than11.0
C. Upper H 0: mugreater than or equals11.0 Upper H Subscript a: muless than11.0
D. Upper H 0: mugreater than11.0 Upper H Subscript a: muless than or equals11.0
E. Upper H 0: munot equals11.0 Upper H Subscript a: muequals11.0
F. Upper H 0: muless than11.0 Upper H Subscript a: mugreater than or equals11.0
(b) Use technology to find the P-value.
Pequals = (Round to three decimal places as needed.)
(c) Decide whether to reject or fail to reject the null hypothesis.
Which of the following is correct?
A. Fail to reject Upper H 0 because the P-value is less than the significance level.
B. Reject Upper H 0 because the P-value is greater than the significance level.
C. Reject Upper H 0 because the P-value is less than the significance level.
D. Fail to reject Upper H 0 because the P-value is greater than the significance level.
(d) Interpret the decision in the context of the original claim.
A. At the 5% level of significance, there is sufficient evidence to reject the claim that the mean number of classroom hours per week for full-time faculty is greater than 11.0.
B. At the 5% level of significance, there is sufficient evidence to reject the claim that the mean number of classroom hours per week for full-time faculty is 11.0.
C. At the 5% level of significance, there is not sufficient evidence to reject the claim that the mean number of classroom hours per week for full-time faculty is less than 11.0.
D. At the 5% level of significance, there is not sufficient evidence to reject the claim that the mean number of classroom hours per week for full-time faculty is 11.0. Click to select your answer(s).
a. Here claim is that mean is 11
So hypothesis is
A. vs
b. Sample mean is
Create the following table.
data | data-mean | (data - mean)2 |
11.2 | 1.0375 | 1.07640625 |
9.8 | -0.3625 | 0.13140625 |
13.2 | 3.0375 | 9.22640625 |
8.1 | -2.0625 | 4.25390625 |
5.4 | -4.7625 | 22.68140625 |
9.5 | -0.6625 | 0.43890625 |
14.5 | 4.3375 | 18.81390625 |
9.6 | -0.5625 | 0.31640625 |
Find the sum of numbers in the last column to get.
So standard deviation is
So test statistics is
Hence P value is TDIST(0.83,7,2)=0.4339
c. As P value is greater than alpha=0.05, we fail to reject the null hypothesis
Correct answer is
D. Fail to reject Upper H 0 because the P-value is greater than the significance level.
d. Hence we have sufficient evidence to support the claim that mean is 11
So answer here is D. At the 5% level of significance, there is not sufficient evidence to reject the claim that the mean number of classroom hours per week for full-time faculty is 11.0.