Introduction to Statistics

Return to Statistics

Welcome to statistics! Here are some of the basics:

A population is the group of interest.


 * Example: Everyone in the world.

A sample is a a group that is representative of the population.


 * Example: People in the United States.

A statistic is a characteristic or measure obtained by using the data values from a sample.

A parameter is a characteristic or measure obtained by usig the data values from an entire population.

Since it is generally difficult to obtain data values from an entire population, statistics are used to estimate parameters.

Rounding
We all know how to round... for those of you who forgot: If the last digit is < 5 then you round down, if the last digit is > 5 then you round up.

In statistics, rounding should not be done until the final calculation!