The following data are from an experiment designed to investigate the perception of corporate ethical values among individuals who are in marketing. Three groups are considered: management, research and advertising (higher scores indicate higher ethical values).
Marketing Managers Marketing Research Advertising
4 6 11
3 6 12
2 5 11
3 5 10
4 6 11
2 5 11
a. Use α = 0.5 to test for a significant difference in perception among the three groups. Calculate the value of the test statistic (to 2 decimals)