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sample mean

(symbol: X̄, M) the arithmetic average (mean) of a set of scores from cases or observations in a subset drawn from a larger population. Because each score contributes equally to this index of central tendency, it can be affected greatly by outliers. Many widely used statistical tests are based on the comparison of sample means.

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Psychology term of the day

February 22nd 2025

incentive motivation

incentive motivation

1. in Hull’s mathematico-deductive theory of learning, an inducement, such as the expectation of a reward or punishment, that serves as an intervening variable or mediator to influence response strength. See also stimulus-intensity dynamism.

2. more generally, any motivation induced by a positive reinforcer.