8. Which of the following must be true for an estimator of a population parameter to be ono
a. The sampling distribution of the estimator is normal.
b. The expected value of the estimator is equal to the population parameter.
C. The sampling distribution of the estimator is the same shape as the distribution of the
population parameter.
The variability of the sampling distribution of the estimator is equal to the variability of the
population parameter.
e. The variability of the sampling distribution of the estimator is less than the variability of the
population parameter.