Instruction:
• Please write down your answer clearly. Show your work for calculation questions.
• The homework assignment is due at the start of class on Wednesday, Dec 11th. Feel free to turn in assignment early. Homework will not be accepted over email.
Q1. For all two-sample tests, the sample sizes must be equal in the two groups.
True/False? (If false, correct the statement.)
Answer:
Q2. In testing for the differences between the means of 2 independent populations where the standard deviations in each population are unknown but assumed equal, what is the degrees of freedom?
Answer:
Q3. Are managers in district A more motivated than mangers in district B? A randomly selected group of each were administered the Sarnoff Survey of Attitudes Toward Life (SSATL), which measures motivation for upward mobility. The SSATL scores are summarized below.
District A District B
Sample Size 211 100
Sample Mean SSATL Score $\mu_1 = 65.75$ $\mu_2 = 79.83$
Sample Std. Dev $S_1 = 11.07$ $S_2 = 6.41$
Give the null and alternative hypotheses to determine if the mean SSATL score of district B managers ($\mu_2$) differs from the mean SSATL score of district A managers ($\mu_1$).
Answer: $H_0$: and $H_a$: