Microsoft Office Tutorials and References

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**Chapter 11: Frequency Distributions**

CHAPTER
11

Frequency Distributions

In this chapter you will find out how to generate frequency distributions and fre-

quency distribution charts from a data set. Frequency distributions enable you to

better understand the data and the way it is arranged rather than just looking at the

data or the statistics. Frequency distribution allows you to see if the data is sym-

metric, skewed, or flat and detect other information that the statistics could provide.

I will use the same data used in Chapter 10; you will find the data in the Excel

file called Chapter 11. I calculated various statistics in Chapter 10 for that same

data. Two important values were found that will help in determining the frequency

distribution range: the lowest and the highest values. The lowest value is 61 and 129

is the highest. See Figure 11.1.

The first step is to create a list of bins in column F, which will be used to establish

the boundaries for the groups I wish to form for the frequency. In other words, each

one of these bins represents the
upper limit
of the group

s frequency occurrence.

Since I established that the lowest number, or MIN, is 61 and the highest number is

129, I created bins that will encompass this range. I used 70 as the first bin in order to

count all of the numbers/values below 70 (and above 61 the lowest number). I used

130 as the upper limit of the highest group/bin since the largest number found was

1211. The rule of thumb, for frequency distributions, is to find the range of values

(MIN and MAX values) and to create anywhere from 5 to 15 bins. I chose to use

seven bins/groups in this example.

I typed the word Frequency in cell G1. This word will be visible later for my

chart. The results of my frequency calculations are going to be in the range G2:G8.

See Figure 11.1.

’

FIGURE 11.1
Frequency Bins Are in F2:F8