A data value is considered _______ if its z-score is less than minus−2 or greater than 2.

Solution:

Z-score is a numerical measurement used to describe a value's relationship to the mean of a group of values.

Z-score is measured in terms of standard deviations of values from their mean.

If a Z-score is 0, it means that the data point's score is identical to the mean score, while a Z-score of 1.0 would indicate a value that is one standard deviation from the mean.

z-score is a measure of how close the given data point is to the mean of the values given with the standard deviation.

We know that

If the z-score is greater than or equal to -2, or less than or equal to -2, then the data is ordinary

If the z-score is less than -2 or greater than 2, then the data is unusual.

Therefore, a data value is considered unusual if its z-score is less than minus 2 or greater than 2.

A data value is considered _______ if its z-score is less than minus−2 or greater than 2.

Summary:

A data value is considered unusual if its z-score is less than minus -2 or greater than 2.