are Expected mean/var of sample equal to population mean/var

Question

When working out the expected mean of a sample, is that similar to the expected mean for the population? Similarly with variance too?

Answer 1

The population mean is usually the true average for the population but it is often unattainable.

A sample mean is an estimate of a population mean. So yes in a way, the Expected mean of a sample is similar to the expected mean of a population.

Variance works similarly too. Population variance is definitely good to have but that is if you are able to obtain it. It's very tedious to achieve hence sample variance is simply just a statistic of the sample!

• https://www.statisticshowto.com/probability-and-statistics/descriptive-statistics/sample-variance/
• https://www.statisticshowto.com/population-variance/
• https://socratic.org/questions/what-s-the-difference-between-the-population-mean-of-a-variable-the-distribution