Boxplot

A box plot, also known as a box-and-whisker plot, is a visual representation of a dataset's distribution. It displays five key summary statistics: the minimum value, the first quartile (Q1), the median (Q2), the third quartile (Q3), and the maximum value. The box represents the interquartile range (IQR), which contains 50% of the data. Whiskers extend from the box to the minimum and maximum values, excluding outliers. Outliers are often plotted as individual points beyond the whiskers. Box plots are useful for comparing the distribution of different datasets, identifying outliers, and assessing the spread and skewness of data.

Minimum value: The smallest value in the dataset.
First quartile (Q1): The value below which 25% of the data falls.
Median (Q2): The middle value of the dataset.
Third quartile (Q3): The value below which 75% of the data falls.
Maximum value: The largest value in the dataset.

Interpreting a Box Plot:

Box: Represents the interquartile range (IQR), which contains 50% of the data.
Whiskers: Extend from the box to the minimum and maximum values, excluding outliers.
Outliers: Plotted as individual points beyond the whiskers.

Example:

Consider the following dataset: 2, 3, 5, 7, 9, 11, 13, 15, 17, 19

- Minimum: 2
- Q1: 5
- Median: 10
- Q3: 15
- Maximum: 19
Draw the box plot:
- Draw a number line.
- Draw a box from Q1 (5) to Q3 (15).
- Draw a vertical line inside the box to represent the median (10).
- Draw whiskers from the box to the minimum (2) and maximum (19).

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