What does the term "bell curve" refer to?

The term "bell curve" refers to a specific type of distribution of population scores, which is formally known as a normal distribution. In this context, the "bell curve" illustrates how a standardized set of data is distributed, with the majority of scores clustering around the mean and fewer scores appearing as you move away from the mean in either direction. This creates a symmetrical, bell-shaped graph where the highest point represents the average score, while the tails represent the extremes of the data set.

This concept is important in psychology and statistics because it allows for the understanding of variability and the likelihood of certain scores occurring within a population. For example, many psychometric tests, such as IQ tests, are designed so that most individuals score near the average, with progressively fewer scoring very high or very low. This reinforces the significance of the normal distribution in analyzing data in psychology.