Chapter 2 – Frequency Distributions

In this chapter, we are going to learn how to produce our first descriptive statistics, frequency distributions.  Frequency distributions allow us to organize the data that we have collected so that we can start making some sense of it.

When we perform research, we are typically measuring a number of people, either our population or our sample.  Because individuals will vary on the measurement we will then have a number of scores of which we will need to make some sense.  This making sense is the focus of descriptive statistics.  They help us start to understand a group of scores.

When exploring the scores from a group of people, statisticians will want to look at the distribution of those scores. Because people vary on the variables that we measure, their scores are “distributed” or spread out. We can then look at the distribution of scores and see how many individuals had the various scores. A frequency distribution depicts how all the individuals in a group of scores are distributed among the different scores.

Frequency distributions are simply made up of two components:

• Categories, scores, or groups of scores on the measurement
• A count (frequency) of how many people are in each category, score, or group of scores

There are two types frequency distributions: (1) frequency tables and (2) frequency graphs.