A researcher collects scores and finds that the sum of the squared differences from the mean is . Apply the calculations described in the text to compute both the variance and the standard deviation for this dataset, showing your work.
Question: A researcher collects scores and finds that the sum of the squared differences from the mean is . Apply the calculations described in the text to compute both the variance and the standard deviation for this dataset, showing your work.
Sample answer: The variance is calculated as . The standard deviation is the square root of this variance, which is .
Key points:
- Calculate variance by dividing the sum of squared differences by the number of scores ().
- Calculate standard deviation by taking the square root of the variance ().
Rubric: The student must show the calculation for variance () and the subsequent calculation for standard deviation ().
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Research Methods in Psychology - 4th American Edition @ KPU
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