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Chapter 3: Measures of Variability
We can compare the variability of the middle 50% for data sets through the
if their medians are the same. Hence we can use to compare two data
sets.
Note:
If two data sets have the same median, then the data set with the larger
interquartile range will have at least a larger variability in the middle 50% of
the ordered data set.
Example 3-5:
Consider the following two data sets denoted by A and B.
Data Set A:
-12, -3, 1, 5, 8, 10, 13, 15, 17, 22, 30.
Data Set B:
-100, -31, -14, -5, 2, 10, 15, 20, 35, 50, 100.
Compute the quartiles and the interquartile ranges for the data
sets.
Solution:
The results are given below.
Data Set A:
= 1, median (
) = 10,
= 17,
= 16
Data Set B:
= -14, median (
) = 10,
= 35,
= 49
The results were generated using the
Basic Statistics
workbook. The results
are shown in
Figure 3-7
.
Click here for the Basic Statistics Workbook