Find an unbiased estimate of the population variance from the sample 3, 5, 7, 9, 11, 13.

Answer and explanation

Correct answer: D. 14

  1. Step 1: Mean , and . Step 2. Unbiased estimate , which is . Answer: 14. Why not the others: : That divides by instead of . 70: That is the sum of squared deviations, not divided by anything. 8: That is the sample mean, not the variance.

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