Normal Distribution Curve

Characteristics of the Normal Distribution

• It is symmetrical — Half the cases are to one side of the center; the other half is on the other side.
• The distribution is single peaked, not bimodal or multi-modal
• Most of the cases will fall in the center portion of the curve and as values of the variable become more extreme they become less frequent, with “outliers” at each of the “tails” of the distribution few in number. 
• It is only one of many frequency distributions but the one we will focus on for most of this discussion.
• The Mean, Median, and Mode are the same.
• Percentage of cases in any range of the curve can be calculated.