Chapter 15

A score of 550 would be one-half of a standard deviation above the mean. We could call that +.5 standard deviations above the mean. A score of 320 would be 1.8 standard deviations below the mean, or -1.8. This is such a useful concept that there is a name for it: z-score. The z-score is how many standard deviations away from its mean a given ... ................
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