Short Answer Quiz

1. M.C. finished a research study examining job satisfaction and the number of sick days used by employees the previous year. The summary totals of raw data are as follows:

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M. C.'s computations of the variance and standard deviation of the 5 scores are shown below. Evaluate this work and describe the problems with the computations.

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2. Why is n - 1 used in the computation of sample variance and not population variance?