Question

A researcher computes the definitional formula for SS, and finds that Σ(x − M) = 44. If this is a sample of 12 scores, then what would the value of sample variance be using the computational formula?

A. 3.7

B. 4.0

C. 44

D. not possible to know because the scores are not given

Answer 1

Option B.

Explanation:

Given information:

Σ(x − M) = 44

where, M is mean.

Sample size = 12

The computational formula for sample variance is

`s^2=(\sum (x-M)^2)/(N-1)`

where, M is sample mean and N is sample size.

Substitute Σ(x − M) = 44 and N=12 in the above formula.

`s^2=(44)/(12-1)`

`s^2=(44)/(11)`

`s^2=4.0`

The sample variance is 4.0.

Therefore, the correct option is B.