The following information is obtained for a sample of 25 observations taken from a population.
SSxx = 274.600, se = .932, and ŷ = 280.56 – 3.77x
a. Make a 95% confidence interval for B.
b. Using a significance level of .01, test whether B is negative.
c. Testing at the 5% significance level, can you conclude that B is different from zero?
d. Test if B is different from – 5.20. Use α = .01.