This paper attempts to determine whether the relationship between education and income results because schooling allows individuals to earn higher income or because higher income individuals purchase more of all normal goods, including schooling. Education is treated as a joint product, producing potential wage gains and utility simultaneously. The framework permits estimation of the rental price of a unit of education, net of consumption effects. The major finding is that education does causally produce income. By moving from 0 years of schooling to 12 years, the mean individual approximately triples his wealth. More surprising is that education is a bad." Individuals stop short of acquiring the wealth-maximizing level of education because of the disutility associated with school attendance.

This paper attempts to determine whether the relationship between education and income results because schooling allows individuals to earn higher income or because higher income individuals purchase more of all normal goods, including schooling. Education is treated as a joint product, producing potential wage gains and utility simultaneously. The framework permits estimation of the rental price of a unit of education, net of consumption effects. The major finding is that education does causally produce income. By moving from 0 years of schooling to 12 years, the mean individual approximately triples his wealth. More surprising is that education is a bad." Individuals stop short of acquiring the wealth-maximizing level of education because of the disutility associated with school attendance.

The theory of human capital is agnostic on what constitutes firm-specific skills. The theory specifies that specific skills contribute to productivity only at the current firm. A broader approach lets all skills be general, but firms use them with different weights attached. For example, computer programming, economics, and accounting are general skills, but there may be only one firm that wants workers trained in all three. One implication is that wage profiles and the split of human capital costs depend on thickness of the market. Another is that firms pay for what appears to be general training.

Some have observed that individuals perform worse after being promoted. The Peter principle, which states that people are promoted to their level of incompetence, suggests that something is fundamentally misaligned in the promotion process. This view is unnecessary and inconsistent with the data. Below, it is argued that ability appears lower after promotion purely as a statistical matter. Being promoted is evidence that a standard has been met. Regression to the mean implies that future ability will be lower, on average. Firms optimally account for the regression bias in making promotion decisions, but the effect is never eliminated. Rather than evidence of a mistake, the Peter principle is a necessary consequence of any promotion rule. Furthermore, firms that take it into account appropriately adopt an optimal strategy. Usually, firms inflate the promotion criterion to offset the Peter principle effect, and the more important the transitory component is relative to total variation in ability, the larger the amount that the standard is inflated. The same logic applies to other situations. For example, it explains why movie sequels are worse than the original film on which they are based and why second visits to restaurants are less rewarding than the first.

Common culture and common language facilitate trade between people. Minorities have incentives to become assimilated and to learn the majority language so that they have a larger pool of potential trading partners. The value of assimilation is larger to someone from a small minority than to one from a large minority group. When a society has a very large majority of individuals from one culture, individuals from minority groups will be assimilated more quickly. Assimilation is less likely when an immigrant's native culture and language is broadly represented in his new country. Also, when governments protect minority interests directly, incentives to be assimilated into the majority culture are reduced. Both factors may explain the recent rise in multiculturalism. Individuals do not properly internalize the social value of assimilation and ignore the benefits others receive when they learn the majority language and become assimilated. In a pluralistic society, a government policy that encourages diverse cultural immigration over concentrated immigration is likely to increase the welfare of the population. In the absence of strong offsetting effects, policies which encourage multi- culturalism reduce the amount of trade and have adverse welfare consequences. Conversely, policies that subsidize assimilation and the acquisition of majority language skills can be socially beneficial. The theory is tested and confirmed by examining U.S. Census data, which reveals that the likelihood that an immigrant will learn English is inversely related to the proportion of the local population that speaks his or her native language.

Sellers sometimes practice a form of false advertising known as bait and switch. A low-priced good is advertised but replaced by a different good at the showroom. the practice is surprising since advertising the wrong good discourages the appropriate buyers from shopping, attracting customers who will be disappointed when they see the good. Firms bait and switch to draw a greater number of shoppers. The cost is that some who would have bought the good that is for sale may not bother to look. Under a variety of conditions, bait and switch is a profitable strategy resulting in a fully rational equilibrium with false advertising.

Sellers sometimes practice a form of false advertising known as bait and switch. A low-priced good is advertised but replaced by a different good at the showroom. the practice is surprising since advertising the wrong good discourages the appropriate buyers from shopping, attracting customers who will be disappointed when they see the good. Firms bait and switch to draw a greater number of shoppers. The cost is that some who would have bought the good that is for sale may not bother to look. Under a variety of conditions, bait and switch is a profitable strategy resulting in a fully rational equilibrium with false advertising.

Personnel managers often argue that equitable pay treatment manifested as wage compression is useful because it reduces disharmony among workers. But it is far from obvious that a compressed salary structure is morale improving since better workers may feel disenchanted by this scheme. However, when workers' rewards are based on relative comparisons, salary compression reduces uncooperative behavior that is detrimental to the firm. Relative comparisons imply that some reference group must be selected. The major result is that within the relevant groups, some wage compression is efficient.

Personnel managers often argue that equitable pay treatment manifested as wage compression is useful because it reduces disharmony among workers. But it is far from obvious that a compressed salary structure is morale improving since better workers may feel disenchanted by this scheme. However, when workers' rewards are based on relative comparisons, salary compression reduces uncooperative behavior that is detrimental to the firm. Relative comparisons imply that some reference group must be selected. The major result is that, within the relevant groups, some wage compression is efficient.

This paper offers an explanation of the use of mandatory-retirement clauses in labor contracts. It argues that the date of mandatory retirement is chosen to correspond to the date of voluntary retirement, but the nature of the optimal wage profile results in a discrepancy between spot wage and spot VMP (value of the worker's marginal product). This is because it is preferable to pay workers less than VMP when young and more than VMP when old. By doing so the "agency" problem is solved, so the contract with mandatory retirement is Pareto efficient. A theory of agency is presented and empirical evidence which supports the hypothesis is provided.