Question

Problem 3 (4 Points) David Desreumaux, V train P of Human Resources of American First Banks (AFB), is reviewing the employee ing programs of AFB banks. Based on a recent census of personnel, David knows that the variance of teller training time in the Southeast region is 8, and he wonders if the variance in the Southwest region is the same number. His staff randomly selected personnel files for 15 tellers in the Southwest Region, and determined that their mean training time was 25 hours and that the standard deviation was 4 hours Assume that teller training time is normally distributed. Using to test whether the variance of teller training time in the Southeast region is significantly different from the variance in the Southwest region. a-0.10, set Use this sample information

Answer 1

null hypothesis:     Ho:				σ2 =	8
Alternate hypothesis: Ha:				σ2 ≠	8

for sample size n:				=	15
s2				=	16.00

for 10 % CI and given df critical values of F      =			13.996		&	23.685
Decision rule:reject Ho if test statistic F in critical region:			13.996		< X2 >	23.685

test stat :

=χ2=(n-1)s2/σ2=

28.00

as test statistic falls in rejection region ; we reject null hypothesis

we have sufficient evidence to conclude that variance of teller training time in the southeast region is significantly different from the variance in the southwest region