← STAT 20070

Section 2 · Lecture 07 · Normal Distribution

Normal Shape Explorer

Every Normal distribution is determined by two numbers. The mean μ sets its location and the standard deviation σ sets its width. Because the total area under the curve must always equal 1, σ also sets its height.

Mean, μ (location)
Standard deviation, σ (width)

Compare curves

Presets

Mean = median = mode

Peak height, f(μ)

Total area under the curve

Working it out

Compared with the reference N(0, 1)

μ does not appear in the peak height, so sliding the curve left or right never changes its shape. Only σ changes the height: doubling σ doubles the width and halves the peak, which keeps the total area equal to 1.