Specifies the precise location of each X-value within a distribution. The sign of the z-score (+ or -) signifies whether the score is above the mean (positive) or below(negative). The numerical value of the z-score specifies the distance from the mean by counting the number of the standard deviations between X and
Raw Score
A score by itself does not necessarily provide much information about its position within a distribution. these original, unchanged scores that are the direct result of measurement are often called raw scores. to make raw scores more meaningful, they are often transformed into new values that contain more information. this transformation is one purpose for z-scores
z-score formula
Deviation Score
; it measures the distance in points between X and
It indicates whether X is located above or below the mean
z-score transformation
The entire distribution of X values are transformed into a distribution of z-scores. The new distribution of z-scores has characteristics that make the z-score transformation a very useful tool
Standardized Distribution
Is composed of scores that have been transformed to create predetermined values for and . Standardized distributions are used to make dissimilar distributions comparable.