• Selected
• Entire List

Abstract:
Output per worker varies enormously across countries. Why? On an accounting basis, our analysis shows that differences in physical capital and educational attainment can only partially explain the variation in output per worker we find a large amount of variation in the level of the Solow residual across countries. At a deeper level, we document that the differences in capital accumulation, productivity, and therefore output per worker are driven by differences in institutions and government policies, which we call social infrastructure. We treat social infrastructure as endogenous, determined historically by location and other factors captured in part by language.

Abstract:
Output per worker varies enormously across countries. Why? On an accounting basis, our analysis shows that differences in physical capital and educational attainment can only partially explain the variation in output per worker--we find a large amount of variation in the level of the Solow residual across countries. At a deeper level, we document that the differences in capital accumulation, productivity, and therefore output per worker are driven by differences in institutions and government policies, which we call social infrastructure. We treat social infrastructure as endogenous, determined historically by location and other factors captured in part by language.

Abstract:
Output per worker varies enormously across countries. Why? On an accounting basis, our analysis shows that differences in physical capital and educational attainment can only partially explain the variation in output per worker--we find a large amount of variation in the level of the Solow residual across countries. At a deeper level, we document that the differences in capital accumulation, productivity, and therefore output per worker are driven by differences in institutions and government policies, which we call social infrastructure. We treat social infrastructure as endogenous, determined historically by location and other factors captured in part by language.

Abstract:
Broadband, or high-speed access to the Internet, has generated significant economic benefits. Certain regulations, however, are slowing investment and deterring entry into the broadband market. In this statement, we make two recommendations that would remedy these regulatory defects and thereby lower artificial barriers to competitive provision of broadband services.

Abstract:
We describe a new index of the current and historical returns to venture-type capital. The conceptual basis for the index is the value of a continuously reinvested value-weighted portfolio of all venture-backed and similar pre-public companies. It provides a metric for private equity comparable to the S&P 500 for public equity. We build the index from valuations revealed in episodic transactions in the companies' shares - private placements of new rounds of equity funding, IPOs, acquisitions, and liquidations. Our approach to dealing with the episodic nature of the data is similar to the one used in constructing indexes of real-estate value from transaction data for individual properties. We have extended earlier sources of data to deal with selection bias - we tracked down unfavorable valuations that were less likely to be reported in the earlier data. We also use econometric techniques to handle the remaining selection bias. The resulting index has important uses in marking venture portfolios to market and in assessing the performance of venture investments.

Abstract:
We describe a new index of the current and historical returns to venture-type capital. The conceptual basis for the index is the value of a continuously reinvested value-weighted portfolio of all venture-backed and similar pre-public companies. It provides a metric for private equity comparable to the S&P 500 for public equity. We build the index from valuations revealed in episodic transactions in the companies' shares - private placements of new rounds of equity funding, IPOs, acquisitions, and liquidations. Our approach to dealing with the episodic nature of the data is similar to the one used in constructing indexes of real-estate value from transaction data for individual properties. We have extended earlier sources of data to deal with selection bias - we tracked down unfavorable valuations that were less likely to be reported in the earlier data. We also use econometric techniques to handle the remaining selection bias. The resulting index has important uses in marking venture portfolios to market and in assessing the performance of venture investments.

venture, venture capital, private equity, returns

Abstract:
Output per worker varies enormously across countries. Why? Our analysis shows that differences in social infrastructure are important sources of this variation. According to our results, a high-productivity country (i) has institutions that favor production over diversion, (ii) has a low rate of government consumption, (iii) is open to international trade, (iv) has at least some private ownership, (v) speaks an international language, and (vi) is located in a temperate latitude far from the equator. A favorable social infrastructure helps a country both by stimulating the accumulation of human and physical capital and by raising its total factor productivity.

Abstract:
In the title of his 1989 Richard T. Ely lecture to the American Economic Association, David Landes asked, "Why are we so rich and they so poor?" It is an odd fact that the subsequent explosion of empirical work on economic growth, has rarely returned to this question, choosing to focus instead on explaining differences in average growth rates across countries, computed over several decades. In this essay and in recent research (Hall and Jones 1996), we examine economic levels instead of economic growth.

Note: This is not an abstract but is the initial paragraph of the paper.

Abstract:
Potential competition restrains the prices of an incumbent seller when the incumbent can alter the environment perceived by an entrant in a way that both discourages entry and lowers prices. When the product has network effects, the incumbent can make its product ubiquitous and place the potential entrant at a disadvantage because customers have experience with the incumbent's product. A primary tool for making a product ubiquitous is low pricing. Hence potential competition lowers the prices of network products. We develop a quantitative model for the desktop software business embodying these principles.

oligopoly, markov-perfect equilibrium, limit pricing, potential competition, Microsoft

Abstract:
Output per worker varies enormously across countries. Why? Our analysis shows that differences in governmental, cultural, and natural infrastructure are important sources of this variation. According to our results, a high-productivity country (i) has institutions that favor production over diversion, (ii) is open to international trade, (iii) has at least some private ownership, (iv) speaks an international language, and (v) is located in a temperate latitude far from the equator. A favorable infrastructure helps a country both by stimulating the accumulation of human and physical capital and by raising its total factor productivity.

Abstract:
Health care extends life. Over the past half century, Americans have spent a rising share of total economic resources on health and have enjoyed substantially longer lives as a result. Debate on health policy often focuses on limiting the growth of health spending. We investigate an issue central to this debate: can we understand the growth of health spending as the rational response to changing economic conditions - notably the growth of income per person? We estimate parameters of the technology that relates health spending to improved health, measured as increased longevity. We also estimate parameters of social preferences about longevity and the consumption of non-health goods and services. The story of rising health spending that emerges is that the diminishing marginal utility of non-health consumption combined with a rising value of life causes the nation to move up the marginal-cost schedule of life extension. The health share continues to grow as long as income grows. In projections based on our parameter estimates, the health share reaches 33 percent by the middle of the century.

Abstract:
I estimate adjustment costs for labor and capital from the Euler equations for factor demand. For both factors, I find relatively strong evidence against substantial adjustment costs. My estimates use annual data from two-digit industries. I investigate the potential effects of three types of specification error: (1) aggregation over time, (2) aggregation over firms with heterogeneous demand shocks, and (3) estimation of a convex adjustment-cost technology in the presence of non-convex discrete adjustment costs. I find that the likely biases from these specification errors are relatively small. My results support the view that rents arising from adjustment costs are relatively small and are not an important part of the explanation of the large movements of the values of corporations in relation to the reproduction costs of their capital.

adjustment cost, investment,Tobin's q

Abstract:
New data compel a new view of events in the labor market during a recession. Unemployment rises almost entirely because jobs become harder to find. Recessions involve little increase in the flow of workers out of jobs. Another important finding from new data is that a large fraction of workers departing jobs move to new jobs without intervening unemployment. I develop estimates of separation rates and job-finding rates for the past 50 years, using historical data informed by detailed recent data. The separation rate is nearly constant while the job-finding rate shows high volatility at business-cycle and lower frequencies. I review modern theories of fluctuations in the job-finding rate. The challenge to these theories is to identify mechanisms in the labor market that amplify small changes in driving forces into fluctuations in the job-finding rate of the high magnitude actually observed. In the standard theory developed over the past two decades, the wage moves to offset driving forces and the predicted magnitude of changes in the job-finding rate is tiny. New models overcome this property by invoking a new form of sticky wages or by introducing information and other frictions into the employment relationship.

Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.

Abstract:
If firms purchase capital up to the point where there is no further marginal benefit, and the firms' securities are equal in value to the capital, then the market value of securities measures the quantity of capital. I explore the implications of this hypothesis using data from U.S. non-farm, non-financial corporations over the past 50 years. The hypothesis implies that corporations have formed large amounts of intangible capital, especially in the past decade. The resources for expanding capital have come from the output of the existing capital. An endogenous growth model can explain the basic facts about corporate performance, with only a modest increase in the productivity of capital in the 1990s.

Abstract:
The signatories to this document are economists who have studied telecommunications, auctions, and competition policy. While we may disagree about the stimulus package, we believe that it is important to implement mechanisms that make stimulus spending as efficient as possible. To that end, we have come together to encourage the National Telecommunications Information Agency (NTIA) and Rural Utilities Service (RUS) to adopt auction mechanisms to allocate broadband stimulus grants.

The broadband stimulus NOI asks which mechanisms NTIA and RUS should use to distribute grants and how those mechanisms address shortcomings in traditional grant and loan programs. In this note we explain why procurement auctions are more efficient and more consistent with the stimulus goals of allocating funds quickly than a traditional grant review process. We recommend that NTIA/RUS use procurement auctions to distribute at least part of the stimulus funds.

The American Recovery and Reinvestment Act (ARRA) requires NTIA/RUS to distribute $7.2 billion in broadband subsidies. The broadband component of the Act has dual, and not entirely consistent, objectives of providing immediate economic stimulus and improving broadband service. NTIA/RUS faces a formidable challenge in determining how to spend the money quickly and efficiently in ways that meet these goals. The traditional grant application process is long, complicated, and involves subjective and arbitrary decisions regarding which projects to fund. In other words, requesting and reviewing grant applications is not an effective way to implement the plan.

Procurement auctions, in contrast, provide a mechanism that can allocate grant money quickly, efficiently, and according to well-defined rules. As a result, procurement auctions offer NTIA/RUS the most promising method of maximizing broadband improvement while also creating some level of “temporary, timely, and targeted” stimulus. We therefore strongly recommend that NTIA/RUS adopt procurement auctions as its preferred method of distributing grants.

This memo has three parts. First, it explains why the traditional grant application process is unsuitable for this task and why procurement auctions are better suited. Second, it sketches out a procurement auction plan. This plan is intended to be a starting point from which auction design experts would proceed to build and implement a fully functional auction. Finally, we explain that even if policymakers are skeptical of procurement auctions, one could be implemented quickly as part of an initial tranche of stimulus funding in order to test its efficacy relative to traditional approaches. This approach would allow NTIA/RUS to quickly expand upon or modify the procurement auction program in subsequent funding rounds.

Abstract:
No abstract is available for this paper.

Abstract:
No abstract is available for this paper.

Abstract:
No abstract is available for this paper.

Abstract:
Optimization of the part of consumers is shown to imply that the marginal utility of consumption evolves according to a random walk with trend. To a reasonable approximation, consumption itself should evolve in the same way. In particular, no variable apart from current consumption should be of any value in predicting future consumption. This implication is tested with time-series data for the postwar United States. It is confirmed for real disposable income, which has no predictive power for consumption, but rejected for an index of stock prices. The paper concludes that the evidence supports a modified version of the life cycle-permanent income hypothesis.

Abstract:
Some workers bargain with prospective employers before accepting a job. Others could bargain, but find it undesirable, because their right to bargain has induced a sufficiently favorable offer, which they accept. Yet others perceive that they cannot bargain over pay; they regard the posted wage as a take-it-or-leave-it opportunity. Theories of wage formation point to substantial differences in labor-market equilibrium between bargained and posted wages. The fraction of workers hired away from existing jobs is another key determinant of equilibrium, because a worker with an existing job has a better outside option in bargaining than does an unemployed worker. Our survey measures the incidences of wage posting, bargaining, and on-the-job search. We find that about a third of workers had precise information about pay when they first met with their employers, a sign of wage posting. We find that another third bargained over pay before accepting their current jobs. And about 40 percent of workers could have remained on their earlier jobs at the time they accepted their current jobs.

jobs, wages, bargaining, equilibrium

Abstract:
Some workers bargain with prospective employers before accepting a job. Others could bargain, but find it undesirable, because their right to bargain has induced a sufficiently favorable offer, which they accept. Yet others perceive that they cannot bargain over pay; they regard the posted wage as a take-it-or-leave-it opportunity. Theories of wage formation point to substantial differences in labor-market equilibrium between bargained and posted wages. The fraction of workers hired away from existing jobs is another key determinant of equilibrium, because a worker with an existing job has a better outside option in bargaining than does an unemployed worker. Our survey measures the incidences of wage posting, bargaining, and on-the-job search. We find that about a third of workers had precise information about pay when they first met with their employers, a sign of wage posting. We find that another third bargained over pay before accepting their current jobs. And about 40 percent of workers could have remained on their earlier jobs at the time they accepted their current jobs.

Abstract:
No abstract is available for this paper.

Abstract:
The labor market occupies center stage in modern theories of fluctuations. The most important phenomenon to explain and understand in a recession is the sharp decline in employment and jump in unemployment. This chapter for the Handbook of Macroeconomics considers explanations based on frictions in the labor market. Earlier research within the real business cycle paradigm considered frictionless labor markets where fluctuations in the volume of work effort represented substitution by households between work in the market and activities at home. A preliminary section of the chapter discusses why frictionless models are incomplete they fail to account for either the magnitude or persistence of fluctuations in employment. And the frictionless models fail completely to describe unemployment. The evidence suggests strongly that consideration of unemployment as a third use of time is critical for a realistic model. The two elements of a theory of unemployment are a mechanism for workers to lose or leave their jobs and an explanation for the time required for them to find new jobs. Theories of mechanism design or of continuous re-bargaining of employment terms provide the first. The theory of job search together with efficiency wages and related issues provides the second. Modern macro models incorporating these features come much closer than their predecessors to realistic and rigorous explanations of the magnitude and persistence of fluctuations.

Abstract:
null

Abstract:
In this paper, a theory of the natural or equilibrium rate of unemployment is built around a theory of the duration of employment. Evidence is presented that most unemployed workers became unemployed because their previous jobs came to an end; only a minority are on temporary layoff or have just entered the labor force. Thus, high-unemployment labor markets are generally ones where jobs are brief and there is a large flow of newly jobless workers. The model of the duration of employment posits that employment arrangements are the efficient outcome of the balancing of workers` and employers` interests about the length of jobs. Full equilibrium in the labor market also requires that the rate at which unemployed workers find new jobs be efficient. The factors influencing the resulting natural unemployment rate are discussed. Under plausible assumptions, the natural rate is independent of the supply or demand for labor. Only the costs of recruiting, the costs of turnover to employers, the efficiency of matching jobs and workers, and the cost of unemployment to workers are likely to influence the natural rate of unemployment strongly. Since these are probably stable over time, the paper concludes that fluctuations in the natural unemployment rate are unlikely to contribute much to fluctuations in the observed unemployment rate.

Abstract:
When a job-seeker and an employer meet, find a prospective surplus, and bargain over the wage, conditions in the outside labor market, including especially unemployment, may be irrelevant. The job-seeker's threat point in the bargain is to delay bargaining, not to terminate bargaining and resume search at other employers. Similarly, the employer's threat point is to delay bargaining, not to terminate it. Consequently, the outcome of the bargain depends on the relative costs of delay to the parties, not on the results of irrational threats to disclaim any bargain. In a model of the labor market that otherwise adopts all of the features of the standard Mortensen-Pissarides model, unemployment is much more sensitive to changes in productivity than in the standard model, because feedback through the wage is absent. We also present models where the wage bargain is in partial contact with conditions in the labor market.

Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.

Abstract:
Adjustment costs determine the dynamics of the response of an industry's output to a shift in demand. Absent any adjustment costs, an increase in demand not accompanied by any change in factor prices raises output, labor, capital, and materials in the same proportion. In the presence of adjustment costs, the elasticity of the response of factors with higher costs is less than one while the elasticity of those without adjustment costs exceeds one. I develop a model of industry dynamics to capture these properties and a related econometric framework to infer adjustment costs from the observed ratios of factor responses to output responses. I find relatively precise evidence of moderate adjustment costs.

Abstract:
Under conditions of natural monopoly, private contracts or government regulation may attempt to avoid inefficiency by setting up a pricing formula. Once the capital stock is chosen,the right price to charge the buyer is marginal cost. But the point of this paper is that marginal-cost pricing provides the wrong incentives for the choice of the capital stock by the seller. If the seller can achieve a high price by deliberately under-investing and driving up marginal cost, there will be asystematic tendency toward too small a capital stock. One type of contract or regulatory policy that avoids this problem charges marginal cost to each buyer, but provides a revenue to the seller that is equal to long-run unit cost, not short-run marginal cost. Such a contract or policy will make the price, in the sense of the revenue of the seller per unit of output, appear to be unresponsive to market conditions.

Abstract:
Macroeconomists%u2014%u2014especially those studying monetary policy%u2014%u2014often view the business cycle as a transitory departure from the smooth evolution of a neoclassical growth model. Important ideas contributed by Friedman, Lucas, and the developers of the sticky-price macro model generate this type of aggregate behavior. But the real-business cycle model shows that the neoclassical model implies anything but smooth growth. A purely neoclassical model, devoid of anything resembling a business cycle in the sense of transitory departures from neoclassical equilibrium, nevertheless explains most of the volatility of GDP growth at all frequencies. Monetary policymakers looking to a neoclassical model to provide the neutral levels of key variables-potential GDP, the natural rate of unemployment, and the equilibrium real interest rate, need to solve a complicated and controversial model to find these constructs. They cannot take average or smoothed values of actual data to find them. Further, low-frequency movements of unemployment suggest a failure of the basic idea that departures from the neoclassical equilibrium are transitory. I discuss new theories of the labor market capable of explaining the low-frequency movements of unemployment. I conclude that monetary policymakers should not try to discern neutral values of real variables. Some branches of modem theory do not support the concepts of potential GDP, the natural rate of unemployment, and the equilibrium real interest rate. Even the theories that do support the concepts suggest that measurement in real time is impractical.

Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.

Abstract:
No abstract is available for this paper.

Abstract:
Following a recession, the aggregate labor market is slack - employment remains below normal and recruiting efforts of employers, as measured by vacancies, are low. A model of matching frictions explains the qualitative responses of the labor market to adverse shocks, but requires implausibly large shocks to account for the magnitude of observed fluctuations. The incorporation of wage-setting frictions vastly increases the sensitivity of the model to driving forces. I develop a new model of wage friction. The friction arises in an economic equilibrium and satisfies the condition that no worker-employer pair has an unexploited opportunity for mutual improvement. The wage friction neither interferes with the efficient formation of employment matches nor causes inefficient job loss. Thus it provides an answer to the fundamental criticism previously directed at sticky-wage models of fluctuations.

Abstract:
Previous research has suggested that firms in a number of industries have considerable market power, in the sense that their prices exceed their marginal costs. However, the observed profits of those industries are not nearly as high as would occur under full exploitation of the market power with a constant returns technology. Rather, because of fixed costs associated with a minimum scale of operation or for other reasons, industry equilibrium occurs at a point where no abnormal returns are earned, even though market power still exists. This inference is supported by an empirical study that shows that most industries hold capital far beyond the point that would minimize cost given their actual output. In this sense, the industries have chronic excess capacity.

Abstract:
We investigate the stochastic relation between income and consumption (specifically, consumption of food) within a panel of about 2,000 households. Our major findings are:

1. Consumption responds much more strongly to permanent than to transitory movements of income.

2. The response to transitory income is nonetheless clearly positive.

3. A simple test, independent of our model of consumption, rejects a central implication of the pure life cycle-permanent income hypothesis.

4. The observed covariation of income and consumption is compatible with pure life cycle-permanent income behavior on the part of 80 percent of families and simple proportionality of consumption and income among the remaining 20 percent.

As a general matter, our findings support the view that families respond differently to different sources of income variations. In particular, temporary income tax policies have smaller effects on consumptions than do other, more permanent changes in income of the same magnitude.

Abstract:
Governments determine the size of the unit of value just as they determine the length of the length and weight of physical units of measure. What are the different ways that a government can control the size of the unit of value, that is, control the price level? In general, the government designates a resource gold, paper currency, another country's currency and defines its unit of value as a particular amount of that resource. An interesting variant proposed by Irving Fisher in 1913 and implemented more recently in Chile is to alter the resource content of the unit to stabilize the price level. Another idea is to alter the interest rate paid on reserves in a way that stabilizes the price level.

Abstract:
No abstract is available for this paper.

Abstract:
One of the important determinants of the response of saving and consumption to the real interest rate is the elasticity of intertemporal substitution. That elasticity can be measured by the response of the rate of change of consumption to changes in the expected real interest rate. A detailed study of data for the twentieth-century United States shows no strong evidence that the elasticity of intertemporal substitution is positive. Earlier studies flnding substantially positive elasticities are shown to suffer from a bias related to the timing of instrumental variables.

Abstract:
Issues of labor supply are at the heart of macroeconomic explanations of the large cyclical fluctuations of output observed in modern economies. This paper starts with a serious empirical examination of the view that the labor market is always in balance-that every observed combination of employment and compensation is a point of intersection of the relevant supply and demand curves. I will call this the "intertemporal substitution" model of fluctuations. According to this model, workers are willing to shift their hours of work from one year to another in response to modest shifts in relative wages. The paper goes on to point out a strong implication of the pure inter- temporal substitution model, namely, the irrelevance of changes in the money supply for the labor supply function. A model where markets clear instantly ought to obey full monetary neutrality. The data refute this implication absolutely unambiguously. The money stock unambiguously shifts the labor supply function. The pure substitution model seems untenable in the light of this evidence. The paper then turns to explanations of the nonneutrality of money in the short run. According to the most carefully worked out line of thought, monetary shocks cause workers to make inappropriate intertemporal shifts in labor supply, because they lack complete information about the source of aggregate shocks and are forced to respond in the same way to real and nominal disturbances. Finally, the paper turns to the view that, in the short run, labor supply is largely irrelevant to the determination of aggregate employment.

Abstract:
The standard venture-capital contract rewards entrepreneurs only for creating successful companies that go public or are acquired on favorable terms. As a result, entrepreneurs receive no help from venture capital in avoiding the huge idiosyncratic risk of the typical venture-backed startup. Entrepreneurs earned an average of $9 million from each company that succeeded in attracting venture funding. But entrepreneurs are generally specialized in their own companies and bear the burden of the idiosyncratic risk. Entrepreneurs with a coefficient of relative risk aversion of two would be willing to sell their interests for less than $1 million at the outset rather than face that risk. The standard financial contract provides entrepreneurs capital supplied by passive investors and rewards entrepreneurs for successful outcomes. We track the division of value for a sample of the great majority of U.S. venture-funded companies over the period form 1987 through 2005. Venture capitalists received an average of $5 million in fee revenue from each company they backed. The outside investors in venture capital received a financial return substantially above that of publicly traded companies, but that the excess is mostly a reward for bearing risk. The pure excess return measured by the alpha of the Capital Asset Pricing Model is positive but may reflect only random variation.

Abstract:
The evolution of the aggregate labor market is far from smooth. I investigate the success of a macro model in replicating the observed levels of volatility of unemployment and other key variables. I take variations in productivity growth and in exogenous product demand (government purchases plus net exports) as the primary exogenous sources of fluctuations. The macro model embodies new ideas about the labor market, all based on equilibrium - the models I consider do not rest on inefficiency in the use of labor caused by an inappropriate wage. I find that non-standard features of the labor market are essential for understanding the volatility of unemployment. These models include simple equilibrium wage stickiness, where the sticky wage is an equilibrium selection rule. A second model based on modern bargaining theory delivers a different kind of stickiness and has a unique equilibrium. A third model posits fluctuations in matching efficiency that may arise from variations over time in the information about prospective jobs among job-seekers. Reasonable calibrations of each of the three models match the observed volatility of unemployment.

Abstract:
Earnings are the flow of value created by corporations. I concentrate on the concept called EBITDA - earnings before interest, taxes, depreciation, and amortization. This measure captures the results of the substantive non-financial activities of corporations and corresponds to the rental price of capital multiplied by the quantity of capital. I measure earnings per dollar of capital for all U.S. corporations and in 5 selected industries. I develop a competitive benchmark for the level of earnings, which takes account of adjustment costs, taxes, depreciation, and the financial opportunity cost of funds. I find that aggregate corporate earnings track the benchmark reasonably closely, leaving a relatively small unexplained component. Thus evidence of the flow of value gives little help in explaining the large discrepancies found in earlier work in the level of the market value of claims on corporations relative to the replacement cost of the capital stock. At the industry level, I find more volatility of both actual and benchmark earnings, with a high correlation between the two in 3 of the 5 industries.

Abstract:
A time series is concentrated if the expectation of its current value is a negative function of a moving average of past values up to all but the most recent past. Job destruction has the property of concentration in a model of heterogeneous jobs because an adverse shock destroys jobs in plants close to the margin of shutdown. Until other plants drift close to that margin, there are fewer plants that are vulnerable to another adverse shock. Concentration is easy to spot in the autocorrelations of a time series, which will be negative except for the first few lags. A simple model generates data displaying concentration. Data on job destruction and employment change for U.S. manufacturing show unambiguous evidence of concentration. According to the simple model, job creation is more persistent and thus less concentrated than is destruction, a property reflected in the data as well.

Abstract:
Sir John Hick's Value and Capital provided the theoretical foundation for an important element of modern macroeconomics. Intertemporal substitution - deferral or acceleration of economic activity in response to the real interest rate and other incentives - is the mechanism generally relied upon in equilibrium theories of macroeconomics to explain the irregular evolution of the economy over time. Even theorists who question the pure market-clearing paradigm are concerned with intertemporal substitution in measuring deadweight burden of fluctuations. This paper surveys recent empirical evidence on intertemporal substitution with regard to the type of fluctuations model introduced in Value and Capital.

Abstract:
No abstract is available for this paper.

Abstract:
One of the productive activities engaging the work force is reorganizing. When factors of production are better matched, productivity is higher. The probabilistic matching model of Diamond, Mortensen, and others provides a way to make the idea of reorganization precise. Because the flow of organizational effort generates benefits lasting well into the future, it is appropriate to think of organizational capital. Unemployment-job seeking-is one of the inputs to organization. The flow of organizational effort represented by unemployment is analogous to the flow of physical investment. When an adverse technology shock causes job destruction, the economy substitutes the formation of new organizational capital for the flow of output. An increase in the interest rate can cause intertemporal substitution toward lower job destruction and less reorganization, but this effect may not come into play for a brief unexpected increase, and may be overwhelmed by intertemporal substitution in physical capital.

Abstract:
I consider three views of the labor market. In the first, wages are flexible and employment follows the principle of bilateral efficiency. Workers never lose their jobs because of sticky wages. In the second view, wages are sticky and inefficient layoffs do occur. In the third, wages are also sticky, but employment governance is efficient. I show that the behavior of flows in the labor market strongly favors the third view. In the modern U.S. economy, recessions do not begin with a burst of layoffs. Unemployment rises because jobs are hard to find, not because an unusual number of people are thrown into unemployment.

Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.

Abstract:
Consumption and income tend to move together; the correlation of their first differences is about 0.14. In most accounts, the correlation is attributed to the upward slope of the consumption function. When the publicis better off, they consume more. But in the microeconomic theory of the household, income is a variable chosen by the household. Choosing to workmore, and therefore to consume less time away from work, is a sign of diminished well being.The structural relation between earnings and consumption should have a negative slope.The explanation of the observed positive correlation of consumption and income must rest on shifts of the consumption-income relation, not movements along it. An examination of data for the U.S. in the twentieth century shows that the slope of the consumption-income relation has been approximately zero. Shifts in consumer behavior explain the positive observed correlation; they are an important, but not dominant, source of overall fluctuations in the aggregate economy.

Abstract:
No abstract is available for this paper.

Abstract:
No abstract is available for this paper.

Abstract:
Unemployment arises from frictions in the matching of job-seekers and employers. The level of resources that employers devote to evaluating applicants for jobs is a key factor in the magnitude of the frictions. Unemployment will be low if employers can review applicants cheaply. The cost of evaluation per hire depends on the fraction of applicants who are qualified for the job. Applicants may be better informed about their qualifications than are employers. If incentives induce self-selection by job-seekers, so that they apply mainly for jobs where they are qualified, friction and thus unemployment will be low. Self-selection is strongest in markets where unemployment is low and jobs are easy to find. Because of this positive feedback, the equilibrium in a market with self-selection is fragile - unemployment is sensitive to its determinants. Self-selection provides a mechanism for amplification of small changes in the determinants of unemployment.

Abstract:
No abstract is available for this paper.

Abstract:
Problems of defining and measuring unemployemnt in the contemporary American economy are examined here using data from the official employment survey. The paper finds that only a minority of the unemployed conform to the conventional picture of a worker who has lost one job and is looking f or another job. Other important categories are those who have jobs but are not at work because the jobs have not yet started or because of layoff, workers who are in normal spells between temporary jobs, people who are looking into the possibility of work as an alternative to household duties, school, or retirement, and people who have come back into the labor force. None of these categories is dominant. One of the most significant findings is the large number of the unemployed (close to a million in 1977) who are looking for temporary work. Another important finding is that only a minority of the unemployed are looking for work as their major activity during the week of the survey. The majority of those classified officially as unemployed are identified by the household as keeping house, going to school, or retired.

Abstract:
No abstract is available for this paper.

Abstract:
Among the ways a product or labor market might operate is the following: All firms quote the same price or wage. Customers or job-seekers search among sellers until they find one willing to sell them or employ them. They do not need to consider the possibility that another seller or employer might offer a better deal, since all offers are identical. Under prevailing prices or wages, the small participants in the market - customers and workers - have very limited responsibilities for processing information. By contrast, where markets are equilibrated by conscious search for the best price or wage, the small participants face complex problems of gathering and interpreting information. Adherence to prevailing prices and wages may explain part of the macroeconomic puzzle of price and wage stickiness and the sensitivity of real variables to nominal disturbances.

Abstract:
What are the fundamental driving forces of macroeconomic fluctuations? In particular, why do people spend more time working in booms and less in recessions? These are basic questions of macroeconomics. Recent thinking has emphasized technology shifts, preference shifts, and changes in government purchases as likely driving forces. It is useful to distinguish atemporal and intertemporal effects of the driving forces. Under standard assumptions, the technology shift has no effect through atemporal channels because income and substitution effects exactly offset. A straightforward decomposition of movements of employment attributes most of them to the atemporal effects of preference shifts.

Abstract:
No abstract is available for this paper.

Abstract:
Much recent thought has been devoted to the macroeconomic importance of the existence of wage contracts. Still, some puzzling features of the most conspicuous form of wage bargaining, that done formally by employers and labor unions, deserve further theoretical attention. Among these important features are: 1. Collective bargaining agreements are rarely contingent on outside events even though the parties have very imperfect knowledge of prospective economic conditions during the period of the contract. The only important exception is the indexing of wages to the cost of living. 2. Employers are permitted wide discretion in determining the level of employment when demand shifts unexpectedly. As employment varies, total compensation varies according to a formula established in the agreement. 3. Agreements are not permanent but are renegotiated on a regular cycle. 4. In the process of renegotiation, the current state of demand has little impact on the new wage schedule. On the other hand, current wages in other industries have an important influence. This feature especially has been denied or ignored by economic theorists even though it is a prominent part of the thinking of labor economists on wage determination.

Abstract:
In a recession, jobs are destroyed and inventories are liquidated. I concentrate on the intertemporal mechanisms that result in economy-wide job destruction and inventory runoffs. Forces that raise the real interest rate -- especially temporarily -- also cause destruction and runoffs. I consider a model where the job destruction decision is made efficiently, will full consideration of the search costs imposed on discharged workers. I also consider a model of inefficient job destruction, where employers discharge workers who are paid fixed wages as long as they are employed. The impulse response functions for these models resemble those found in data for the United States. A shock that causes a jump in the expected real interest rate results in an immediate spike of job destruction and inventory liquidation, followed by a declining pattern of additional destruction and runoff.

Abstract:
Government guarantees of private debt deplete equity. The depletion is greatest during periods when the probability of a guarantee payoff is highest. In a setting otherwise subject to Modigliani-Miller neutrality, firms issue guaranteed debt up to the limit the government permits. Declines in asset values raise debt in relation to asset values and thus deplete equity directly, under the realistic assumption that the government is unable to enforce rules calling for marking asset values to market. Less widely recognized is that guaranteed debt creates an incentive to pay equity out to owners - such a payout lowers the value of the firm's call option on its assets by less than the amount of the payout. I build a simple dynamic equilibrium model of an economy that would have a constant consumption/capital ratio but for debt guarantees. Exogenous changes in asset values cause major swings in allocations as participants respond to changing incentives. Periods when default is unusually likely because asset values have fallen are times of abnormally high consumption/capital ratios. The withdrawal of equity from firms to pay for the consumption will turn out to be free on the margin if the firm defaults. Consumers concentrate their consumption during the periods when consumption is cheap. Because these periods are transitory, they generate expectations of negative consumption growth, which implies that interest rates are low. Thus guarantees generate substantial volatility throughout the economy.

Abstract:
This paper sets forth a simple general structural model of aggregate output, the interest rate, and the price level. The core of the model is the determination of the level of output as a product-market equilibrium, either competitive or oligopolistic, possible indeterminate because of thick-market externalities. Monetary non-neutrality can affect either product demand or product supply. In either case, monetary policy has leverage over output as well as the price level. The paper develops a two-diagram analysis intended to replace the aggregate demand-aggregate supply diagram.

Abstract:
During World War II and the Korean War, real GDP grew by about half the amount of the increase in government purchases. With allowance for other factors holding back GDP growth during those wars, the multiplier linking government purchases to GDP may be in the range of 0.7 to 1.0, a range generally supported by research based on vector autoregressions that control for other determinants, but higher values are not ruled out. New Keynesian macro models have multipliers in that range as well. On the other hand, neoclassical models have a much lower multiplier, because they predict that consumption falls when purchases rise. The key features of a model that delivers a higher multiplier are (1) the decline in the markup ratio of price over cost that occurs in those models when output rises, and (2) the elastic response of employment to an increase in demand. These features alone deliver a fairly high multiplier and they are complementary to another feature associated with Keynes, the linkage of consumption to current income. Multipliers are higher - perhaps around 1 .7 - when the nominal interest rate is at its lower bound of zero, as it was during 2009.

Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.

Abstract:
No abstract is available for this paper.

Abstract:
In the standard venture capital contract, entrepreneurs have a large fraction of equity ownership in the companies they found and are paid a sub-market salary by the investors who provide the money to develop the idea. The big rewards come only to those whose companies go public or are acquired on favorable terms, forcing entrepreneurs to bear a substantial burden of idiosyncratic risk. We study this burden in the case of high-tech companies funded by venture capital. Over the past 20 years, the typical venture-backed entrepreneur earned an average of $4.4 million from companies that succeeded in attracting venture funding. Entrepreneurs with a coefficient of relative risk aversion of two and with less than $0.7 million would be better off in a salaried position than in a startup, despite the prospect of an average personal payoff of $4.4 million and the possibility of payoffs over $1 billion. We conclude that startups attract entrepreneurs with lower risk aversion, higher initial assets, preferences for entrepreneurship over employment, and optimistic beliefs about the payoffs from their products.

Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.