Question

when the sampling distribution of a statistic centers exactly around the parameter it estimates we can say that the statistic is which of the following? a. statistically significant b. unbiased c. equal to the parameter d. normally distributed question 9 a study was conducted to estimate μ, the mean commute distance that all employed u.s. adults travel to work. suppose a random sample of 49 employed u.s. adults gives a mean commute distance of 22 miles and that from prior studies, the population standard deviation is assumed to be σ = 8.4 miles. based on this information, what would be the point estimate for μ?

Explanation:

1. For the first question: The definition of an unbiased statistic is that the sampling - distribution of the statistic is centered exactly around the parameter it estimates. Statistical significance refers to the likelihood that an observed result is not due to chance. Just because a statistic is unbiased doesn't mean it is equal to the parameter (it's an estimate). And being centered around a parameter doesn't imply a normal distribution.
2. For the second question: The point - estimate of the population mean $\mu$ is the sample mean $\bar{x}$. Given a sample mean commute distance of 22 miles, this is the point - estimate for $\mu$.

Answer:

1. B. Unbiased
2. 22 miles