Answer:
A statistic is said to be unbiased if the mean of its sampling distribution is equal to the true value of the parameter being estimated.
Step-by-step explanation:
A parameter is a number that describes the population.
A statistic is a number that describes a sample.
A statistic used to estimate a parameter is unbiased if the mean of its sampling distribution is exactly equal to the true value of the parameter being estimated. For example, the mean of a sample is an unbiased estimate of the mean of the population from which the sample was drawn.
A statistic is biased if its expected value is not equal to the parameter.