Box And Whisker Plot Explained

Box And Whisker Plot Explained

What is a Box and Whisker Plot?

A box and whisker plot is a graphical representation of the distribution of data. It is also known as a box-and-whisker diagram. The box and whisker plot shows the median, quartiles, and outliers of the data set. The median is the middle value of the data set when assorted in order. The quartiles are the 25th, 50th, and 75th percentiles of the data set. The outliers are the values that are significantly different from the rest of the data set.

How to Create a Box and Whisker Plot

To create a box and whisker plot, follow these steps:

1. Order the data set from least to greatest.
2. Find the median of the data set.
3. Find the lower quartile (25th percentile).
4. Find the upper quartile (75th percentile).
5. Draw a box from the lower quartile to the upper quartile. The line in the middle of the box is the median.
6. Draw a line from the lower quartile to the smallest value in the data set that is not an outlier.
7. Draw a line from the upper quartile to the largest value in the data set that is not an outlier.
8. Label the box and whisker plot with the name of the data set and the units of measurement.

Example of a Box and Whisker Plot

The following is an example of a box and whisker plot for the data set {1, 2, 3, 4, 5, 6, 7, 8, 9, 10}.

The median of the data set is 5. The lower quartile is 3. The upper quartile is 7. The smallest value in the data set is 1. The largest value in the data set is 10. There are no outliers in the data set.

Uses of Box and Whisker Plots

Box and whisker plots are used to:

• Visualize the distribution of data.
• Compare the distributions of different data sets.
• Identify outliers in a data set.

Advantages of Box and Whisker Plots

Box and whisker plots are:

• Easy to understand.
• Versatile.
• Can be used to compare different data sets.

Disadvantages of Box and Whisker Plots

Box and whisker plots can be:

• Sensitive to outliers.
• Can be difficult to interpret when the data set is large.

Conclusion

Box and whisker plots are a valuable tool for visualizing the distribution of data. They are easy to understand and can be used to compare different data sets. However, they can be sensitive to outliers and can be difficult to interpret when the data set is large.