Changes

'''Statistical sampling''' is the process of finding a representative portion of a large population. In quality control, a percentage of products will be selected at random for testing, and the results ''extrapolated'' to the whole. For example, out of 100,000 [[car]]s produced, 5 will be crash-tested. The results will be assumed to hold for the cars actually sold.

'''Statistical sampling''' is the process of finding a representative portion of a large population. In quality control, a percentage of products will be selected at random for testing, and the results ''extrapolated'' to the population. For example, out of 100,000 [[car]]s produced, 30 might be crash-tested. The results will be assumed to hold for the entire population of cars actually sold.

In [[public opinion]] polls, the people who are contacted must be carefully selected to avoid several kinds of selection bias.

In [[public opinion]] polls, the sample must be carefully done in order to avoid several kinds of bias.

[[Category:Probability and Statistics]]

[[Category:Probability and Statistics]]