## Applied Mathematics## Statistics |

## What is a frequency table? |

A frequency table is a way of summarizing data. In particular, it is a way of displaying how entities (such as scores, number of people, etc.) are divided into intervals, and of counting the number of entities in each interval. The result shows the actual number of entities, and even the percentage of entities in each interval. For example, if we survey the number of people working in the 10 offices in a building, the data set might look like the following:

Another way to present this data is to note how many offices had 1, 2, 3, or 4 people working in them. This is known as finding the frequencies of each of the data values. An example of such a frequency table would be as follows:

number of people frequency | 0 | 1 | 2 | 3 | 4 |

Frequenct | 0 | 4 | 2 | 2 | 2 |

This is a compact way of showing how the data values are distributed between the various number of people. It allows us to see, at a glance, the most “popular” number (also called the “modal class”) of people working in an office for this building’s 10 offices—in this case, a one-person office. Such data can further be visualized with the use of bar charts, histograms, or pie charts.

There are even more ways to see the data from this frequency table. We can also illustrate this chart in terms of percent. In particular, we can say that 40 percent of the offices contain 1 person, 20 percent have 2 people, 20 percent have 3 people, and 20 percent have 4 people.