Question

Is expressed as a deviation from the mean, which involves the concept of standard deviation.

a) Z-score
b) Variance
c) Coefficient of variation
d) Quartile

Answer 1

A Z-score is a measurement of how many standard deviations a specific data point is from the mean. It is the correct answer to the question because it expresses a deviation from the mean via standard deviations.

Step-by-step explanation:

The correct option is a) Z-score. A Z-score is a statistical measurement that describes a value's relationship to the mean of a group of values, measured in terms of standard deviations from the mean. If you have a normal distribution, the Z-score can tell you how many standard deviations an element is from the mean. To find a Z-score, you subtract the mean from the data point and then divide by the standard deviation. For example, if Susan scored a 95 on her biology test and the class mean was 85 with a standard deviation of 5, her Z-score would be calculated as follows: (95 - 85) / 5 which gives a Z-score of 2.0, indicating she scored two standard deviations above the class mean.