AVERAGE PRODUCT CURVE: A curve that graphically illustrates the relation between average product and the quantity of the variable input, holding all other inputs fixed. This curve indicates the per unit output at each level of the variable input. The average product curve is one of three related curves used in the analysis of the short-run production of a firm. The other two are total product curve and marginal product curve. To be quite honest, the average product curve is the least important of the three for economic analysis. Economists are generally more interested in totals and marginals than averages. See also | average product | curve | total product | output | input | variable input | fixed input | marginal product | average cost | law of diminishing marginal returns | average-marginal rule | short-run production | average physical product |