Complete the mcq:
Q1: True or False: The t distribution is used to develop a confidence interval estimate of the population mean when the population standard deviation is unknown.
Q2: True or False: The confidence interval estimate of the population proportion is constructed around the sample proportion.
Q3: True or False: The F test used for testing the difference in two population variances is always a one-tailed test.
Q4: True or False: A completely randomized design with 4 groups would have 6 possible pairwise comparisons.
Q5: A corporation randomly selects 150 salespeople and finds that 66% who have never taken a self-improvement course would like such a course. The firm did a similar study 10 years ago in which 60% of a random sample of 160 salespeople wanted a self-improvement course. The groups are assumed to be independent random samples. Let π1 and π2 represent the true proportion of workers who would like to attend a self-improvement course in the recent study and the past study, respectively.
a. What is/are the critical value(s) when performing a Z test on whether population proportions are different if α = 0.05?
a. ± 1.96
b. ± 2.08
c. ± 1.645
d. -1.96
b. Given the following information, calculate the degrees of freedom that should be used in the pooled-variance t test.
s12 = 4 s22 = 6
n1 = 16 n2 = 25
a. df = 16
b. df = 39
c. df = 25
d. df = 41