Education Technology

Statistics: Normal Probability Plot

by Texas Instruments

Objectives

  • Students will identify the shape of a distribution as being skewed or mound-shaped and approximately symmetric.
  • Students will recognize that a normal probability plot of skewed data is nonlinear and either concave up or concave down.
  • Students will recognize that a normal probability plot of approximately normal data is approximately linear.
  • Students will identify outliers on a normal probability plot.

Vocabulary

  • normal
  • normal probability plot
  • outlier
  • skew
  • symmetric

About the Lesson

This lesson involves creating a normal probability plot for several data sets involving height to examine the appearance of such plots when the distribution is approximately normal.
As a result, students will:

  • Use a histogram to discuss the shape of the distribution of a data set.
  • Describe a normal probability plot for data sets whose distributions are skewed, approximately normal, or contain outliers.
  • Move data values in a dot plot to investigate how the shape of a distribution compares to the linearity of a normal probability plot.