Question

Statistics

Question 1
Why should you always divide by degrees of freedom when calculating the sample variance?

      
a. Because the formula for population variance systematically underestimates the population variance when it is used on only a sample of scores.

       
b. Because the formula for population variance is the best match a sample of scores.

       
c. Because the formula for population variance systematically overestimates the population variance when it used on only a sample of scores.

       
d. None of the above. You should never divide by degrees of freedom when computing sample variance.

QUESTION 2

Under what circumstances must you use the computational formula for SS?

      
a. Never. The computational formula will always give the same result as the definitional formula.

       
b. Never. There is only one formula for SS - the definitional formula.

       
c. Whenever the mean is a whole number.

       
d. Whenever the mean is a decimal and rounding error would occur when summing the squared deviations in the definitional formula.

Answer 1

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