## How do you find outliers on a whisker plot?

When reviewing a box plot, an outlier is defined as a data point that is located outside the whiskers of the box plot. For example, outside 1.5 times the interquartile range above the upper quartile and below the lower quartile (Q1 – 1.5 * IQR or Q3 + 1.5 * IQR).

**Do outliers affect box and whisker plot?**

Outliers are important because they are numbers that are “outside” of the Box Plot’s upper and lower fence, though they don’t affect or change any other numbers in the Box Plot your instructor will still want you to find them. Remember, any numbers that are “outside” the lower or upper fences is considered an outlier.

### What is an outlier on a plot?

An outlier for a scatter plot is the point or points that are farthest from the regression line. If one point of a scatter plot is farther from the regression line than some other point, then the scatter plot has at least one outlier.

**How do you find outliers on a graphing calculator?**

TI-84: Box Plots

- Turn on the Stat Plot. Press [2nd] [Stat Plot].
- Select a Box Plot icon. The first one will show outliers.
- Enter Data in L1 of [Stat]
- View Box Plot by going to [ZOOM] ‘Stat’ (#9).
- Press [Trace] and the arrow keys to view the values of the Min, Q1, Median, Q3, and Max.
- Go to the [2nd] [Stat].

#### How do you find mild and extreme outliers?

Mild vs. Extreme outliers are data points that are more extreme than Q1 – 3 * IQR or Q3 + 3 * IQR. Extreme outliers are marked with an asterisk (*) on the boxplot. Mild outliers are data points that are more extreme than than Q1 – 1.5 * IQR or Q3 + 1.5 * IQR, but are not extreme outliers.

**How do outliers affect the graph?**

An outlier can cause problems if you’re trying to draw conclusions from your data. The outlier is causing the slope of the line of best fit to be less steep than you might expect. If we take out the outlier, (8,1), here is what the graph would look like: Student: I can see that the outlier was affecting the line.

## What is the lower whisker?

Similarly, the lower whisker boundary of the box plot is the smallest data value that is within 1.5 IQR below the first quartile. Here, 1.5 IQR below the first quartile is 52.5 °F and the minimum is 57 °F. Therefore, the lower whisker is drawn at the value of the minimum, which is 57 °F.

**What is an example of an outlier?**

A value that “lies outside” (is much smaller or larger than) most of the other values in a set of data. For example in the scores 25,29,3,32,85,33,27,28 both 3 and 85 are “outliers”.

### What is outlier analysis?

“Outlier Analysis is a process that involves identifying the anomalous observation in the dataset.” Let us first understand what outliers are. Outliers are nothing but an extreme value that deviates from the other observations in the dataset.

**How to make a box and whisker plot?**

Step One: The first step to creating a box and whisker plot is to arrange the values in the data set from least to greatest.

#### What is the outlier in a box plot?

In statistics, an outlier is generally defined as a value that lies beyond the whiskers of a box-and-whisker plot, which are limited to a distance of 1.5*IQR from the upper/lower quartile.

**What is a box plot and when to use it?**

A boxplot is a graph that gives you a good indication of how the values in the data are spread out . Although boxplots may seem primitive in comparison to a histogram or density plot, they have the advantage of taking up less space, which is useful when comparing distributions between many groups or datasets.

## Can box and whisker plot have no whiskers?

On some box plots a crosshatch is placed on each whisker, before the end of the whisker. Rarely, box plots can be presented with no whiskers at all. Because of this variability, it is appropriate to describe the convention being used for the whiskers and outliers in the caption for the plot.