Question

Is it possible to run Levene's test with multiple comparisons in minitab? I am trying to run equal variances, the levene's test, and minitab somehow doesn't like the data. I already made 3 columns in minitab sheet

prompt:

A Datamore Company designs applications software for a number of large firms. A study is conducted to assess the satisfaction of these firms with the supplied software. Datamore decides to determine if the type of industry [Human Resources, Information Technology, Financial, and Insurance] is relevant to satisfaction. Additionally, the company would like to assess the abilities of its sales force [Britknee Phanshear, Megan Hearts, & Jessika Wahlstrom]. They send questionnaires out a number of companies in each of the industries in they do business and ask them to evaluate the company and their contact. The satisfaction scores are found below

	hr	hr	it	it	fn	fn	is	is
bp	74	72	73	71	81	84	84	81
mh	73	71	75	70	83	82	85	83
jw	75	69	71	72	85	82	82	85

So I input the table above in minitab in 3 columns. but when I runt the equal variances test, it comes out an error. Could anyone tell me step by step on how to get the levene's test working?  

Answer 1

A Datamore Company designs applications software for a number of large firms. A study is conducted to assess the satisfaction of these firms with the supplied software. Datamore decides to determine if the type of industry [Human Resources, Information Technology, Financial, and Insurance] is relevant to satisfaction. Additionally, the company would like to assess the abilities of its sales force [Britknee Phanshear, Megan Hearts, & Jessika Wahlstrom]. They send questionnaires out a number of companies in each of the industries in they do business and ask them to evaluate the company and their contact. The satisfaction scores are found below

	hr	hr	it	it	fn	fn	is	is
bp	74	72	73	71	81	84	84	81
mh	73	71	75	70	83	82	85	83
jw	75	69	71	72	85	82	82	85

So I input the table above in minitab in 3 columns. but when I runt the equal variances test, it comes out an error. Could anyone tell me step by step on how to get the levene's test working?  

Enter data in 3 columns.

Stat---ANOVA---Test for equal variances,

Select tha option,

Response data are in a separate column for each factor level

Select the three columns in the Responses,

Ok

You will get

Test for Equal Variances: bp, mh, jw

Method

Null hypothesis	All variances are equal
Alternative hypothesis	At least one variance is different
Significance level	α = 0.05

95% Bonferroni Confidence Intervals for Standard Deviations

Sample	N	StDev	CI
bp	8	5.52914	(3.93251, 11.0938)
mh	8	6.11205	(4.21015, 12.6623)
jw	8	6.58868	(4.59015, 13.4960)

Individual confidence level = 98.3333%

Tests

Method	Test Statistic	P-Value
Multiple comparisons	—	0.719
Levene	0.45	0.643

Calculated levene test value 0.45, P=0.643 which is > 0.05 level.

Ho is not rejected.

Homogeneity of variance assumption is not violated.