The standard score, or z-score, refers to the position of an observation above or below a distribution mean. A positive standard score indicates that the value is above the mean, whereas a negative standard score indicates that the value is below the mean. The value of a standard score is communicated in terms of standard deviations, meaning that an observation with a z-score value of –0.5 indicates an observation that is 0.5 standard deviations below the distribution mean, while an observation with a z-score value of 0.5 indicates an observation that is 0.5 standard deviations above the distribution mean. The standard score is used a number of different ways by communication researchers. Arguably the main advantage of a standard score is that it ...