A simple stochastic model of the firm is constructed in which a dynamic monopolist who maximizes a discounted profits stream subject to labor adjustment costs and given factor prices sets output price as a distributed lag of past wages and input prices. If the observed relation of wages and prices in manufacturing arises solely from this behavior then wages and input prices are exogenous with respect to output prices. In tests using quarterly and monthly series for the straight time wage, an index of raw materials prices and the wholesale price index for manufacturing and its durable and nondurable subsectors this hypothesis cannot be refuted for the period 1955:1 to 1971:11. During the period 1926:1 to 1940:11, however, symmetrically opposite behavior is observed manufacturing wholesale prices are exogenous with respect to the wage rate, a relation which can arise if dynamically monopsonistic firms compete in product markets. Neither structural relation has withstood direct wage and price controls.
It is commonly asserted that with excess plant capacity, expansive policy stimulates output and lowers unemployment without substantially boosting inflation, while at full capacity most of the impact is on inflation. This assertion is critically examined. First, two common definitions of capacity--engineering and economic—are examined and found to be nebulous. The concepts of supply and demand are older, but better. Full capacity is reinterpreted as points where the supply curve is steep and excess capacity as points where it is fairly flat. Then the "Keynesian" model in which stimulative policy shifts only the demand curve is compared to the "classical" model where stimulative policy shifts both demand and supply curves. For the former model the assertion on capacity utilization is correct, while in the latter it is not. Empirical tests are performed to determine whether measured capacity utilization is useful for predicting inflation. The tests are ambiguous, but certainly do not strongly favor capacity utilization.