Mean, median, and mode

Mean

The mean, as you probably know, is just another name for the average. To calculate the mean of a dataset, all you have to do is sum up all the values and divide it by the number of values that you have.

Median

Median is a little bit different. The way you compute the median of the dataset is by sorting all the values (in either ascending or descending order), and taking the one that ends up in the middle.

If you have an even number of data points, then the median might actually fall in between two data points. It wouldn't be clear which one is actually the middle. In that case, all you do is, take the average of the two that do fall in the middle and consider that number as the median.

Median is less susceptible to outliers than the mean.

Mode

Finally, we'll talk about mode. This doesn't really come up too often in practice, but you can't talk about mean and median without talking about mode. All mode means, is the most common value in a dataset.

Mode is usually only relevant to discrete numerical data, and not to continuous data.