Question

8. An outlier is going to be added to a data set. Which is most likely to occur? A. an increase in the MAD, but not the IQR B. a decrease in the MAD, but not the IQR C. an increase in the IQR, but not the MAD D. a decrease in the IQR, but not the

Answer 1

Answer;

It causes an increase in the MAD, but not the IQR

Explanation;

Mathematically, we know that an outlier in a dataset represents a value that is at least 2 standard deviations away from the mean value

While MAD represents the mean absolute deviation, IQR represents the interquartile range

It is expected that the outlier affects the value of the standard deviation

By calculating the MAD, we have to subtract values from the mean and square them and this makes the mean absolute deviation affected by the outlier

Hence, we can conclude that the presence of an outlier increases the mean absolute deviation

For the interquartile range, it only moves the lower quartile and the upper quartile same way and thus, it has no effect on it