Marxian surplus-value theory
Karl Marx accepted Ricardo’s labour theory of value (that the value of a product is based on the quantity of labour that went into producing it), but he subscribed to a subsistence theory of wages for a different reason than that given by the classical economists. In Marx’s estimation, it was not the pressure of population that drove wages to the subsistence level but rather the existence of large numbers of unemployed workers. Marx blamed unemployment on capitalists. He renewed Ricardo’s belief that the exchange value of any product was determined by the hours of labour necessary to create it. Furthermore, Marx held that, in capitalism, labour was merely a commodity: in exchange for work, a labourer would receive a subsistence wage. Marx speculated, however, that the owner of capital could force the worker to spend more time on the job than was necessary for earning this subsistence income, and the excess product—or surplus value—thus created would be claimed by the owner.
Residual-claimant theory
The residual-claimant theory holds that, after all other factors of production have received compensation for their contribution to the process, the amount of capital left over will go to the remaining factor. Smith implied such a theory for wages, since he said that rent would be deducted first and profits next. In 1875 Walker worked out a residual theory of wages in which the shares of the landlord, capital owner, and entrepreneur were determined independently and subtracted, thus leaving the remainder for labour in the form of wages. It should be noted, however, that any of the factors of production may be selected as the residual claimant—assuming that independent determinations may be made for the shares of the other factors. It is doubtful, therefore, that such a theory has much value as an explanation of wage phenomena.
Bargaining theory
The bargaining theory of wages holds that wages, hours, and working conditions are determined by the relative bargaining strength of the parties to the agreement. Smith hinted at such a theory when he noted that employers had greater bargaining strength than employees. Employers were in a better position to unify their opposition to employee demands, and employers were also able to withstand the loss of income for a longer period than could the employees. This idea was developed to a considerable extent by John Davidson, who proposed in The Bargain Theory of Wages (1898) that the determination of wages is an extremely complicated process involving numerous influences that interact to establish the relative bargaining strength of the parties.
This theory argues that no one factor or single combination of factors determines wages and that no one rate of pay necessarily prevails. Instead, there is a range of rates, any of which may exist simultaneously. The upper limit of the range represents the rate beyond which the employer refuses to hire certain workers. This rate can be influenced by many factors, including the productivity of the workers, the competitive situation, the size of the investment, and the employer’s estimate of future business conditions. The lower limit of the range defines the rate below which the workers will not offer their services to the employer. Influences on this rate include minimum wage legislation, the workers’ standard of living, their appraisal of the employment situation, and their knowledge of rates paid to others. Neither the upper nor the lower limit is fixed, and either may move upward or downward. The rate or rates within the range are determined by relative bargaining power.
The bargaining theory is very attractive to labour organizations, for, contrary to the subsistence and wages-fund theories, it provides a very cogent reason for the existence of unions: simply put, the bargaining strength of a union is much greater than that of individuals. It should be observed, however, that historically labourers were capable of improving their situations without the help of labour organizations. This indicates that factors other than the relative bargaining strength of the parties must have been at work. Although the bargaining theory can explain wage rates in short-run situations (such as the existence of certain wage differentials), over the long run it has failed to explain the changes that are observed in the average levels of wages.