PSYC 2021 Lecture Notes - Lecture 5: Squared Deviations From The Mean, Standard Deviation, Raw Score
Document Summary
A z-score speciies the precise locaion of each x value within a distribuion. The sign of the z- score (+ or -) signiies whether the score is above the mean (posiive) or below the mean (negaive). The numerical value of the z-score speciies the distance from the mean by compuing the number of standard deviaions between x and . The purpose of z-scores, or standard scores, is to idenify and describe the exact locaion of each score in a distribuion. A score (x) in a distribuion does not exactly tell you where your posiion is within the actual distribuion (raw scores). To make raw scores meaningful they are transformed into new values that contain more informaion. Transforming x values into z-scores will tell you where the original scores are located. Standardizing takes diferent distribuions and makes them equivalent. The advantage of this is that it is possible to compare distribuions even though they may have been quite diferent before standardizaion.