A z-score of -1.5 for a test score means that the score is what?
Answer and explanation
Correct answer: C. 1.5 standard deviations below the mean
- Step 1: A z-score counts standard deviations from the mean. Step 2. A negative sign means below. Answer: 1.5 standard deviations below the mean. Why not the others: A z-score measures the standardized distance of an observation from the distribution mean expressed in standard deviation units, rather than raw points or percentages.
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