Knowledge that Transforms

This paper presents a model that provides an explanation, based on regime switching in the real interest rate and learning, of why tests based on stock-adjustment models, Euler equations, or decision rules—which emphasize short-run fluctuations in inventories and the interest rate—are unlikely to uncover a negative relationship between inventories and the real interest rate. The model, however, predicts that inventories will respond to long-run movements, that is, to regime shifts in the real interest rate. Tests emphasizing cointegration techniques confirm this prediction and show a significant long-run relationship between inventories and the real interest rate.

If individuals care about their status, defined as their rank in the distribution of consumption of one “positional” good, then the consumer's problem is strategic as her utility depends on the consumption choices of others. In the symmetric Nash equilibrium, each individual spends an inefficiently high amount on the status good. Using techniques from auction theory, we analyze the effects of exogenous changes in the distribution of income. In a richer society, almost all individuals spend more on conspicuous consumption, and individual utility is lower at each income level. In a more equal society, the poor are worse off.

We study race in the labor market by sending fictitious resumes to help-wanted ads in Boston and Chicago newspapers. To manipulate perceived race, resumes are randomly assigned African-American- or White-sounding names. White names receive 50 percent more callbacks for interviews. Callbacks are also more responsive to resume quality for White names than for African-American ones. The racial gap is uniform across occupation, industry, and employer size. We also find little evidence that employers are inferring social class from the names. Differential treatment by race still appears to still be prominent in the U.S. labor market.

On news of a takeover, the sum of the stock market values of the firms involved often falls, and the value of the acquirer almost always does. Does this mean that takeovers do not raise the values of the firms involved? Not necessarily. We set up a model in which the equilibrium number of takeovers is constrained efficient. Yet upon news of a takeover, a target's price rises, the bidder's price falls, and most of the time the joint value of the target and acquirer also falls.

School officials and legislators have long been concerned with the possibility of declining teacher quality (see e.g., Sean Corcoran et al., 2002). Beginning in the 1960's, states began testing prospective teachers in a direct effort to ensure that teachers meet minimum standards for basic skills and subject knowledge. By 1999, 41 states required applicants to pass some sort of standardized certification test. As a theoretical matter, however, the impact of such testing is ambiguous. Test requirements may establish a minimum achievement standard, as their proponents hope. On the other hand, testing and other certification requirements may deter some qualified applicants from teaching if these requirements are perceived as costly. This is the barriers-to-entry story first noted in the occupational licensing context by Milton F. Friedman and Simon Kuznets (1945). Another concern with job applicant testing is the possibility of an adverse impact on minority candidates, who usually do worse on tests (see David Autor and David Scarborough [2003] for a recent study). Paralleling increased state involvement in teacher certification is the increase in teachers' educational credentials, especially in public schools. For example, in 1971, over two-thirds of public-school teachers had a B.A., while only 27 percent had a master's or education specialist's degree. By 1991, however, over half of public school teachers (52.6 percent) had a master's or education specialist's degree. In contrast, the proportion of private-school teachers

Since Gary Becker’s (1964) seminal work, the theoretical and empirical literature on human capital has focused almost exclusively on general-purpose and firm-specific human capital. In this paper we discuss the implications of a third type of human capital, which we call task-specific, and which we believe is potentially as commonplace and as important as the two classic types. By task-specific human capital we mean that some of the human capital an individual acquires on the job is specific to the tasks being performed, as opposed to being specific to the firm. In other words, task-specific human capital is the simple but plausible idea that much of the human capital accumulated on the job is due to task-specific learning by doing. The idea of task-specific human capital is closely related to occupationand industryspecific human capital. In each case, human capital is specific to the nature of the work, not specific to the firm. Hence, when capital is accumulated, multiple firms value the capital, so most (or even all) of the value of the capital will be reflected in the worker’s wage. The main difference between the idea of task-specific human capital and occupationand industryspecific human capital is in how the idea is applied. We argue that task-specific human capital has much wider applicability than suggested (so far) by the occupationand industry-specific human-capital literatures; the specific issues we address are cohort effects, job design, and promotions. Another argument in the literature closely related to ours is the classic argument of Adam Smith (1776) in the Wealth of Nations concerning returns to specialization. Smith’s argument was that, due to learning-by-doing at the level of the task, productivity can be enhanced by having each job entail fewer tasks. We believe that Smith was correct in focusing on learningby-doing at the level of the task as an important idea for thinking about organizations. The goal of our paper is to describe some of the other implications of this idea for the design and operation of organizations.

Lucas (1990) argued that it was a paradox that more capital does not flow from rich countries to poor countries. He rejected the standard explanation of expropriation risk and argued that paucity of capital flows to poor countries must instead be rooted in externalities in human capital formation favoring further investment in already capital rich countries. In this paper, we review the various explanations offered for this “paradox.” There is no doubt that there are many reasons why capital does not flow from rich to poor nations – yet the evidence we present suggests some explanations are more relevant than others. In particular, as long as the odds of non repayment are as high as 65 percent for some low income countries, credit risk seems like a far more compelling reason for the paucity of rich-poor capital flows. The true paradox may not be that too little capital flows from the wealthy to the poor nations, but that too much capital (especially debt) is channeled to “debt intolerant” serial defaulters.

We present a model of the creation of social networks, such as political parties, trade unions, religious coalitions, or political action committees, through discussion and mutual persuasion among their members. The key idea is that people are influenced by those inside their network, but not by those outside. Once created, networks can be "rented out" to politicians who seek votes and support for their initiatives and ideas, which may have little to do with network members' core beliefs. In this framework, political competition does not lead to convergence of party platforms to the views of the median voter. Rather, parties separate their messages and try to isolate their members to prevent personal influence from those in the opposition.

This paper utilizes a plausibly exogenous source of variation in housing assistance generated by public housing demolitions in Chicago to examine the impact of high-rise public housing on student outcomes. I find that children in households affected by the demolitions do no better or worse than their peers on a wide variety of achievement measures. Because the majority of households that leave high-rise public housing in response to the demolitions move to neighborhoods and schools that closely resemble those they left, the zero effect of the demolitions may be interpreted as the independent impact of public housing.