It’s important to know whether we’re talking about a population or a sample, because in this section we’ll be talking about variance and standard deviation, and we’ll use different formulas for variance and standard deviation depending on whether we’re using data from a population or data from a sample.

Read MoreMeasures of central tendency are different ways we’ve come up with to describe the “middle,” “center,” or most typical value of the data. They include the mean, the median, and the mode, and we need to know how to find all three.

Read More