Interpreting z-scores

Front

What is a z-score?

Back

A z-score is a statistical measurement that describes a value's relationship to the mean of a group of values, expressed in terms of standard deviations from the mean.

Front

How is the z-score calculated?

Back

Front

What does a positive z-score indicate?

Back

A positive z-score indicates that the data point is above the mean.

Front

What does a negative z-score indicate?

Back

A negative z-score indicates that the data point is below the mean.

Front

If a data point has a z-score of 0, what does this mean?

Back

A z-score of 0 means the data point is exactly at the mean.

Front

Calculate the z-score for a data point of 85 in a data set with a mean of 80 and a standard deviation of 5.

Back

Front

Calculate the z-score for a data point of 30 in a data set with a mean of 50 and a standard deviation of 10.

Back

Front

What does a z-score of 1.5 indicate?

Back

A z-score of 1.5 indicates that the data point is 1.5 standard deviations above the mean.

Front

What does a z-score of -1.5 indicate?

Back

A z-score of -1.5 indicates that the data point is 1.5 standard deviations below the mean.

Front

If a data point has a z-score of 2, how many standard deviations is it from the mean?

Back

It is 2 standard deviations above the mean.