Quantiles

As we said just a moment ago, the median is the number that occurs at the 50% point in your data. To get a better sense of the range of your data, you might want to know what value is the lowest point in your data. That’s the minimum value of your data set, which is computed using min in R:

min(heights)
#[1] 54.26313

And to get the highest/maximum point in your data set, you should use max in R:

max(heights)
#[1] 78.99874

Together, the min and max define the range of your data:

c(min(heights), max(heights))
#[1] 54.26313 78.99874
range(heights)
#[1] 54.26313 78.99874

Another way of thinking of these numbers is to think of the min as the number that 0% of your data is below and the max as the number that 100% of your data is below. Thinking that way leads to a natural extension: how can you find the number that N% of your data is below? The answer to that question is to use the quantile function in R. The Nth quantile is exactly the number that N% of your data is below.