Contents

## How do you construct a box plot?

To construct a box plot, use a horizontal or vertical number line and a rectangular box. The smallest and largest data values label the endpoints of the axis. The first quartile marks one end of the box and the third quartile marks the other end of the box.

## What are the 5 values needed to create a box plot?

A box and whisker plot —also called a box plot —displays the five -number summary of a set of data. The five -number summary is the minimum, first quartile, median, third quartile, and maximum.

## How do you read box plots?

What is a Boxplot?

- The minimum (the smallest number in the data set).
- First quartile, Q
_{1}, is the far left of the box (or the far right of the left whisker). - The median is shown as a line in the center of the box.
- Third quartile, Q
_{3}, shown at the far right of the box (at the far left of the right whisker).

## What does a box plot tell you?

A boxplot is a standardized way of displaying the distribution of data based on a five number summary (“minimum”, first quartile (Q1), median, third quartile (Q3), and “maximum”). It can also tell you if your data is symmetrical, how tightly your data is grouped, and if and how your data is skewed.

## How do you compare box plots?

Guidelines for comparing boxplots

- Compare the respective medians, to compare location.
- Compare the interquartile ranges (that is, the box lengths), to compare dispersion.
- Look at the overall spread as shown by the adjacent values.
- Look for signs of skewness.
- Look for potential outliers.

## How do you find Q1 and Q3?

Q1 is the median (the middle) of the lower half of the data, and Q3 is the median (the middle) of the upper half of the data. (3, 5, 7, 8, 9), | (11, 15, 16, 20, 21). Q1 = 7 and Q3 = 16.

## Can Excel make box and whisker plots?

Excel doesn’t offer a box-and-whisker chart. Instead, you can cajole a type of Excel chart into boxes and whiskers. Instead of showing the mean and the standard error, the box-and-whisker plot shows the minimum, first quartile, median, third quartile, and maximum of a set of data.

## How do box and whisker plots work?

In a box and whisker plot:

- the ends of the box are the upper and lower quartiles, so the box spans the interquartile range.
- the median is marked by a vertical line inside the box.
- the whiskers are the two lines outside the box that extend to the highest and lowest observations.