Z-Scores

Front

What is a Z-score?

Back

A Z-score indicates how many standard deviations an element is from the mean of a dataset.

Front

What is the formula to find the Z-score for a population?

Back

z = (X - μ) / σ

Front

What does a Z-score of 0 indicate?

Back

A Z-score of 0 indicates that the data point is exactly at the mean.

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

How do you calculate the Z-score for a sample?

Back

z = (X - M) / s, where M is the sample mean and s is the sample standard deviation.

Front

If the mean is 22.8 and the standard deviation is 7, what is the Z-score for x = 20?

Back

-0.4

Front

If the mean is 22 and the standard deviation is 3.1, what is the Z-score for x = 29?

Back

2.26

Front

If the mean is 45 and the standard deviation is 2.1, what is the Z-score for x = 50?

Back

2.38

Front

If the mean is 27 and the standard deviation is 1.4, what is the Z-score for x = 11?

Back

-11.43