Lebo claims that workers in large companies are less work

motivated than workers in small companies. In a previous study involving all

large companies in South Africa, it was found that the average workers’

motivation score on a work motivation questionnaire (where a higher score

indicates a higher level of work motivation) was 50 with a standard deviation

of 15. Lebo plans to present the same questionnaire to a sample of workers from

small companies to determine whether her suspicion is true.

Calculate the effect

size. After making the appropriate calculations, what does she find?

The effective difference between the

motivation level for small companies and those for large companies is - - - -

-.