In a box plot, data value x is considered an outlier if A) x Q3 + 1.0(IQR). B) x Q2 + 1.0(IQR). C) x Q3 + 1.5(IQR). D) x Q2 + 1.5(IQR).

Question

In a box plot, data value x is considered an outlier if A) x < Q1 - 1.0(IQR) or x > Q3 + 1.0(IQR). B) x < Q2 - 1.0(IQR) or x > Q2 + 1.0(IQR). C) x < Q1 - 1.5(IQR) or x > Q3 + 1.5(IQR). D) x < Q2 - 1.5(IQR) or x > Q2 + 1.5(IQR).

Quizplus · Accepted Answer

A common rule of thumb is that any data value outside of Q1 - 1.5(IQR) or Q3 + 1.5(IQR) is considered an outlier. This allows for some variability and outliers that may be present in the data, while still identifying extreme values that may significantly affect the distribution. Answer choice C matches this rule of thumb.

​In a Box Plot, Data Value X Is Considered an Outlier

In a Box Plot, Data Value X Is Considered an Outlier