Question

1. estimating sd the figure below shows two normal curves, both with mean 0. approximately what is the standard deviation of each of these curves?

Explanation:

Step1: Recall normal - curve property

For a normal curve, about 68% of data lies within 1 standard - deviation of the mean.

Step2: Estimate from the graph

The flatter curve has about 68% of data from approximately - 1 to 1, so its SD is about 1. The taller curve has about 68% of data from approximately - 0.4 to 0.4, so its SD is about 0.4.

Answer:

Taller curve: 0.4; Flatter curve: 1