Question

1.Consider the e-billing case. The mean and the standard deviation of the sample of n = 65 payment times are x¯x¯ = 18.4730 and s = 3.9045. Test H₀: μ = 18.6 versus H_a: μ < 18.6 by setting α equal to .01 and using a critical value rule and assume normality of the population. (Round your "t" and "t_0.01" answers to 3 decimal places and p-value answer to 4 decimal places. Negative value should be indicated by a minus sign. Use a statistical software package - e.g., Minitab, MegaStat, etc., to derive the p-value.)

t
t0.01
p-value

2. Bayus (1991) studied the mean numbers of auto dealers visited by early and late replacement buyers. Letting μ be the mean number of dealers visited by all late replacement buyers, set up the null and alternative hypotheses needed if we wish to attempt to provide evidence that μ differs from 4 dealers. A random sample of 100 late replacement buyers yields a mean and a standard deviation of the number of dealers visited of x¯x¯ = 4.42 and s = .65. Using a critical value and assuming approximate normality to test the hypotheses you set up by setting α equal to .10, .05, .01, and .001. Do we estimate that μ is less than 4 or greater than 4? (Round your answers to 3 decimal places.)

H₀ : μ (Click to select)≠= 4 versus H_a : μ (Click to select)=≠ 4.

t =   

tα/2 = 0.05
tα/2 =0.025
tα/2 =0.005
tα/2 =0.0005

There is (Click to select)extremely strongnovery strongstrongweak evidence.

μ is (Click to select)greater thanless than 4.

Answer 1