Understanding IQR and Outliers

What is the formula for IQR (Interquartile Range)?

• Q3 + Q1

• Q3 – Q1

• (Q3 × Q1)/2

• Q3 ÷ Q1

Given the data: 4, 5, 7, 8, 9, 10, 12, 13, 15, 50 What is the IQR?

• 9

• 6

• 7

• 12

How do you detect Outliers using IQR?

• Values smaller than Q1 – 1.5×IQR or larger than Q3 + 1.5×IQR

• Values smaller than Q1 + IQR

• Values larger than Q3 + IQR only

• All values are Outliers

In the same dataset: 4, 5, 7, 8, 9, 10, 12, 13, 15, 50 Is 50 considered an Outlier?

• Yes

• No

• Cannot tell

What does the Box Plot show?

• Only the Mean

• Only the Minimum and Maximum

• The Median, Q1, Q3, and possible Outliers

• The Mode only

In a Box Plot, the line inside the box represents:

• The Mean

• The Mode

• The Median

• The Maximum

If a Box Plot shows many points outside the Whiskers, what does that mean?

• There are no Outliers

• The data is normally distributed

• There are multiple Outliers

• The data is constant