A sample of n observations is taken from a population. When performing statistical inference about a population variance, the appropriate χ²distribution has _____. A) n degrees of freedom B) n - 1 degrees of freedom C) n - 2 degrees of freedom D) n - 3 degrees of freedom

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When performing statistical inference about a population variance, the appropriate distribution is the chi-square distribution with n - 1 degrees of freedom. This is because the sample variance is calculated with n - 1 degrees of freedom (dividing by n - 1 instead of n) in order to account for the fact that estimating the population variance requires using the sample mean, which introduces an additional source of variability. Therefore, when using the sample variance to make inferences about the population variance, we must use the chi-square distribution with n - 1 degrees of freedom.

A Sample of N Observations Is Taken from a Population