There are two Chevrolet dealers in Jamestown, New York. The mean monthly sales at Sharkey Chevy and Dave White Chevrolet are about the same. However, Tom Sharkey, the owner of Sharkey Chevy, believes his sales are more consistent. Below are the numbers of new cars sold at Sharkey in the last 7 months and for the last 8 months at Dave White. Do you agree with Mr. Sharkey? Use the 0.01 significance level. 101 State the decision rule for 0.01 significance level What is the value of F? There is more variation of the monthly sales True/FalseSharkey98785457686470Dave White75818130824658 101 State the decision rule for 0.01 significance level What is the value of F? There is more variation of the monthly sales True/False Solution State the decision rule for 0.01 significance level It is a one-tailed test. The degree of freedom df1=n1-1=7-1=6 The degree of freedom df2=n2-1=8-1=7 Given a=0.01, the critical value isF(0.99, df1=6, df2=7) =7.19 (from F table) The rejection region is if F>7.19, we reject the null hypothesis. -------------------------------------------------------------------------------------------------------------------- What is the value of F? F= s1^2/s2^2 =14.79^2/22.95^2 =0.42 -------------------------------------------------------------------------------------------------------------------- There is more variation of the monthly sales True/False Since F=0.42 is less than 7.19, we do not reject the null hypothesis. So answer is FalseSharkeyDave White69.8669.25mean14.7922.95std. dev.78n.