Reaction times to visual stimulus
The example is a data set that could have arisen as a sample from a normal population. Mention that we don't have enough information to really tell the shape of the underlying population's distribution, but that a normal population seems plausible.
Use the sliders to adjust the normal parameters and match the shapes of the pdf and histogram as well as possible.
This normal population could be used as an approximate model for how the data might have arisen.
The values are reaction times of 40 subjects to a visual stimulus (in hundredths of a second).