What do the horizontal and vertical axes represent in a KDE plot?


#1

Question

In the context of this exercise, what do the horizontal and vertical axes represent in a KDE plot?

Answer

For this lesson, the KDE plots we work will be using univariate data. So, only one of the axes will represent actual values in the data.

The horizontal or x-axis of a KDE plot is the range of values in the data set. This is similar to the x axis for histograms.

The vertical or y-axis of a KDE plot represents the Kernel Density Estimate of the Probability Density Function of a random variable, which is interpreted as a probability differential. The probability of a value being between the points x1 and x2 is the total shaded area of the curve under the two points.