Statistics

In statistics, a sampling distribution or finite-sample distribution is the distribution of a given statistic based on a random sample of size n.

The margin of error is a statistic expressing the amount of random sampling error in a survey's results.

In probability theory, the expected value refers, intuitively, to the value of a random variable one would "expect" to find if one could repeat the random variable process an infinite number of times and take the average of the values obtained.

Getting a reliable sample is important if you want to make good predictions. This lesson will look at examples to give an explanation about biased vs. unbiased samples and how to use a sample to make predictions.