ONLY FOR MAESTRO

_____08eMCsa2x2ExperimentalDesign-QualityandEconomy3.pptx

8. A 2 x 2 Experimental Design: - Quality and Economy (x1 and x2 manipulation checks)

Dr. Boonghee Yoo

RMI Distinguished Professor in Business and

Professor of Marketing & International Business

Run factor analysis for x1 and x2 manipulation check questions.

x1 MC - Perceived service quality

x2 MC - Perceived contribution to local economy

Compute the composite variable for each x MC.

Create x1MC and x2MC.

Run t-test to check if the manipulation is well done.

Test variable (x1MC here):

Interval- or ratio-scaled

variable(s)

Grouping variable (x1 here):

A nominal-scaled variable:

Select two groups that

you want to compare.

Independent-samples t-test

Step 1.

See the sample mean of each group.

See if the mean difference is as expected (e.g., Hi > Low).

Step 2. Levene’s test (Ho: s2group1 = s2group2)

If p-value of Levene’s test > alpha, read the “Equal variances assumed” line.

If p-value < alpha, read the “Equal variances NOT assumed” line.

Step 3. t-test

Read the t-value, which is the test statistics.

And read p-value.

Levene’s test (Ho: s2group1 = s2group2)

The graph confirms a successful manipulation.

The service quality of the “High” scenario is perceived to be higher than that of the “Low” scenario.