How Do You Calculate A Z-Score In Statistics?
In statistics, a z-score (or standard score) is used to compare means from different normally distributed sets of data. The actual score indicates how many standard deviations an observation is above or below the mean. The z-score is useful in research utilizing statistical analysis because it allows for the comparison of observations from different normal distributions. In effect, when items from different data sets are transformed into z-scores, then they may then all be compared. This article will show you how to calculate a z-score (or standard score). The formula for calculating a z-score (or standard score) is: z = (x – μ) / σ The variables in the z-score formula are: z = z-score x = raw score or observation to be standardized μ = mean of the population σ = standard deviation of the population Example of a z-score calculation: You have an observation of 14.75, a population mean of 12.2, and a standard deviation of 1.75.
