If changes in aggregate demand were an important source of macroeconomic fluctuations, real wages would be countercyclical unless markups of price over marginal cost were themselves countercyclical. We thus examine three theories of markup variation at cyclical frequencies. The first assumes...

Hall has pointed out that, when there is perfect competition and price flexibility, labor hoarding alone will not induce the Solow residual measured using labor's share in revenues to be procyclical. We show that, even with perfect competition, a small amount of price rigidity - we assume firms...

Because inputs are scarce, marginal cost should be an increasing function of output. Without changes in this real marginal cost schedule, aggregate output can vary if and only if the markup of price over marginal cost varies. In this review, we discuss the extent to which observed fluctuations...