Knowledge that Transforms

This paper develops a simple macroeconomic model that shows that combin-ing capital market imperfections together with unequal access to investment opportunities across individuals can generate endogenous and permanent fluctua-tions in aggregate GDP, investment, and interest rates. Reducing inequality of access may be a necessary condition for macroeconomic stabilization. Moreover, countercyclical fiscal policies have a role to play: in our model savings are underutilized in slumps because of the limited debt capacity of potential investors. Therefore, the government should issue public debt during recessions in order to absorb those idle savings and finance investment subsidies or tax cuts for investors. The most important single fact about saving and investment activities is that in our industrial society they are generally done by different people and for different reasons. (...) For years there might tend to be too little investment, leading to deflation, losses, excess capacity and unemployment. For other years, there might tend to be too much investment, leading to periods of chronic inflation—unless prudent and proper public policies in the fiscal and monetary fields are followed [Paul A. Samuelson, Economics 8th edition, 1970, pp. 196–198].

We estimate the relative influence of trade versus technology on wages in a “large-country” setting, where technological change affects product prices. Trade is measured by the foreign outsourcing of intermediate inputs, while technological change is measured by expenditures on high-technology capital such as computers. The estimation procedure we develop, which modifies the conventional “price regression,” is able to distinguish whether product price changes are due to factor-biased versus sector-biased technology shifts. In our base specification we find that computers explain about 35 percent of the increase in the relative wage of nonproduction workers, while outsourcing explains 15 percent; both of these effects are higher in other specifications.

High consumer indebtedness threatens future consumption spending if default is expensive. Consumer spending collapsed in 1930, turning a minor recession into the Great Depression. Households were shouldering an unprecedented burden of installment debt. Down payments were large. Contracts were short. Equity in durable goods was therefore acquired quickly. Missed installment pa5niients triggered repossession, reducing consumer wealth in 1930 because households lost all acquired equity. Cutting consumption was the only viable strategy in 1930 for avoiding default. Institutional changes lowered the cost of default by 1938. When recession began again, indebted households chose to default rather than reduce consumption.

This paper analyzes data on 11,600 students and their teachers who were randomly assigned to different size classes from kindergarten through third grade. Statistical methods are used to adjust for nonrandom attrition and transitions between classes. The main conclusions are (1) on average, performance on standardized tests increases by four percentile points the first year students attend small classes; (2) the test score advantage of students in small classes expands by about one percentile point per year in subsequent years; (3) teacher aides and measured teacher characteristics have little effect; (4) class size has a larger effect for minority students and those on free lunch; (5) Hawthorne effects were unlikely.

This paper empirically analyzes a broad range of real exchange rate apprecia-tion episodes. The objective is twofold. First, the paper studies the dynamics of appreciations, using a sample that is not limited to cases that end in crisis (or devaluation). Second, the paper analyzes the mechanism by which overvaluations are corrected. In particular, for various degrees of misalignment we calculate the proportion of the reversions that occur through nominal devaluations rather than through cumulative inflation differentials. The overall conclusion is that in most cases large and medium appreciations are reversed with nominal devaluations. What is the probability that a currency that has appreciated significantly in real terms will require a nominal devaluation? The relevance of this question is easier to understand in the context of recent failed attempts to manage nominal exchange rates. A large number of countries have used the exchange rate as an instru-ment to stabilize inflation and coordinate expectations around an easy focal point. However, with inflation higher at home than

Starting in 1985, (West) German unions began to reduce standard hours on an industry-by-industry basis, in an attempt to raise employment. Whether this “work-sharing” works is theoretically ambiguous. I exploit the cross-industry variation in standard hours reductions to examine their impact on actual hours worked, wages, and employment. Analysis of industry-level data suggests that “work-sharing” may have reduced employment in the period 1984–1994. Using individual data from the German Socio-Economic Panel, I substantiate the union claim of “full wage compensation:” the hourly wage rose enough to offset the decline in actual hours worked.

We examine the relationship between educational inputs—primarily pupilteacher ratios—and school outcomes in South Africa immediately before the end of apartheid government. Black households were severely limited in their residential choice under apartheid and attended schools for which funding decisions were made centrally, by White-controlled entities over which they had no control. The allocations resulted in marked disparities in average class sizes. Controlling for household background variables, we find strong and significant effects of pupilteacher ratios on enrollment, on educational achievement, and on test scores for numeracy.

The paper studies contracting between one principal and N agents in the presence of multilateral externalities. When the principal commits to publicly observed bilateral contracts, inefficiencies arise due to the externalities on agents' reservation utilities. In contrast, when the principal's offers are privately observed, inefficiencies are due to the externalities at efficient outcomes. When the principal can condition her trade with each agent on others' messages, she implements an efficient outcome, while threatening deviators with the harshest possible punishment. However, in the presence of noise that goes to zero more slowly than N goes to infinity, asymptotically agents become nonpivotal, and inefficiency obtains.

Using economic rates of return from World Bank-funded investments, we investigate how country characteristics and policies that influence aggregate performance affect investment productivity. Controlling for other characteristics, countries with undistorted (distorted) macroeconomic, exchange rate, trade, and pricing policies have highly productive (unproductive) investments. No type of project—in tradable or nontradable sectors—can be “insulated” from poor policies, where returns on investments are about ten percentage points lower Productivity increases when policies improve within a country. Projects are also affected, nonlinearly, by the size of the public investment program where policies are undistorted. The results offer new evidence on benefits from policy reform and challenge conventional cost-benefit analysis.

Psychological research indicates that people have a cognitive bias that leads them to misinterpret new information as supporting previously held hypotheses. We show in a simple model that such confirmatory bias induces overconfidence: given any probabilistic assessment by an agent that one of two hypotheses is true, the appropriate beliefs would deem it less likely to be true. Indeed, the hypothesis that the agent believes in may be more likely to be wrong than right. We also show that the agent may come to believe with near certainty in a false hypothesis despite receiving an infinite amount of information.