Mark R. Rosenzweig

Abstract: Household-level panel data from a nationally representative sample of rural Indian households describing the adoption and profitability of high-yielding seed varieties (HYVs) associated with the Green Revolution are used to test the implications of a model incorporating learning by doing and learning spillovers. The estimates indicate that (i) imperfect knowledge about the management of the new seeds was a significant barrier to adoption; (ii) this barrier diminished as farmer experience with the new technologies increased; (iii) own experience and neighbors' experience with HYVs significantly increased HYV profitability; and (iv) farmers do not fully incorporate the village returns to learning in making adoption decisions.

Abstract: In this paper we formulate and estimate a finite-horizon, structural dynamic model of agricultural investment behavior that incorporates the major features of low-income agricultural environments: income uncertainty, constraints on borrowing and rental markets, and the use of investment assets to generate income and smooth consumption. The model is fit to longitudinal Indian household data on farm profits, bullock stocks, and pump sets. The estimated structural parameters are used to assess the effects on the life cycle accumulation of bullocks, agricultural profits, and welfare associated with complete markets and bullock liquidity and with second-best policies that provide assured sources of income to farmers and weather insurance.

Abstract: A significant proportion of migration in low-income countries, particularly in rural areas, is composed of moves by women for the purpose of marriage. We seek to explain these mobility patterns by examining marital arrangements among Indian households. In particular, we hypothesize that the marriage of daughters to locationally distant, dispersed yet kinship-related households is a manifestation of implicit interhousehold contractual arrangements aimed at mitigating income risks and facilitating consumption smoothing in an environment characterized by information costs and spatially covariant risks. Analysis of longitudinal South Indian village data lends support to the hypothesis. Marriage cum migration contributes significantly to a reduction in the variability of household food consumption. Farm households afflicted with more variable profits tend to engage in longer-distance marriage cum migration. The hypothesized and observed marriage cum migration patterns are in dissonance with standard models of marriage or migration that are concerned primarily with search costs and static income gains.

Abstract: In this essay we develop a framework for analysing the major institutions governing the production and exchange of output and the primary factors of production in rural areas. The analysis incorporates general considerations of risk and information constraints jointly with the principal material attributes of agriculture and of agricultural production factors. The framework is used to analyse barriers to the existence of the major intertemporal and factor markets. It is applied specifically to land‐scarce environments for which it provides an internally consistent explanation for many of the well‐documented institutional features of such settings. In addition, the analysis provides new implications for, among other phenomena, the inter‐relationships among ownership holdings, operational scale, family size and factor productivity; for the scarcity of animal rental markets and use of animals as collateral; for the renting out of land by small landowners; and for the existence of plantations for certain crops.

Abstract: We use data on monozygotic twins to obtain improved estimates of the effect of intrauterine nutrient intake on adult health and earnings and thus to evaluate the efficacy of programs aimed at increasing birthweight We use the results to evaluate the bias in cross-sectional estimates and to assess the proposition that health conditions play a major role in determining the world distribution of income We show that there is considerable variation in the incidence of low birthweight across countries, and our estimates suggest that there are real payoffs to increasing body weight at birth Increasing birthweight increases adult schooling attainment and adult height for babies at most levels of birthweight, but has no effect on adult body mass The effect of increasing birthweight on schooling, moreover, is underestimated by 50x% if there is no control for genetic and family background endowments as in cross-sectional estimates We also find evidence that augmenting birthweight among lower-birthweight babies,

Abstract: The second edition of this acclaimed graduate text provides a unified treatment of two methods used in contemporary econometric research, cross section and data panel methods. By focusing on assumptions that can be given behavioral content, the book maintains an appropriate level of rigor while emphasizing intuitive thinking. The analysis covers both linear and nonlinear models, including models with dynamics and/or individual heterogeneity. In addition to general estimation frameworks (particular methods of moments and maximum likelihood), specific linear and nonlinear methods are covered in detail, including probit and logit models and their multivariate, Tobit models, models for count data, censored and missing data schemes, causal (or treatment) effects, and duration analysis. Econometric Analysis of Cross Section and Panel Data was the first graduate econometrics text to focus on microeconomic data structures, allowing assumptions to be separated into population and sampling assumptions. This second edition has been substantially updated and revised. Improvements include a broader class of models for missing data problems; more detailed treatment of cluster problems, an important topic for empirical researchers; expanded discussion of "generalized instrumental variables" (GIV) estimation; new coverage (based on the author's own recent research) of inverse probability weighting; a more complete framework for estimating treatment effects with panel data, and a firmly established link between econometric approaches to nonlinear panel data and the "generalized estimating equation" literature popular in statistics and other fields. New attention is given to explaining when particular econometric methods can be applied; the goal is not only to tell readers what does work, but why certain "obvious" procedures do not. The numerous included exercises, both theoretical and computer-based, allow the reader to extend methods covered in the text and discover new insights.

Abstract: Offering a unifying theoretical perspective not readily available in any other text, this innovative guide to econometrics uses simple geometrical arguments to develop students' intuitive understanding of basic and advanced topics, emphasizing throughout the practical applications of modern theory and nonlinear techniques of estimation. One theme of the text is the use of artificial regressions for estimation, reference, and specification testing of nonlinear models, including diagnostic tests for parameter constancy, serial correlation, heteroscedasticity, and other types of mis-specification. Explaining how estimates can be obtained and tests can be carried out, the authors go beyond a mere algebraic description to one that can be easily translated into the commands of a standard econometric software package. Covering an unprecedented range of problems with a consistent emphasis on those that arise in applied work, this accessible and coherent guide to the most vital topics in econometrics today is indispensable for advanced students of econometrics and students of statistics interested in regression and related topics. It will also suit practising econometricians who want to update their skills. Flexibly designed to accommodate a variety of course levels, it offers both complete coverage of the basic material and separate chapters on areas of specialized interest.

Abstract: The authors examine the effect of consumer reviews on relative sales of books at Amazon.com and Barnesandnoble.com. The authors find that (1) reviews are overwhelmingly positive at both sites, but there are more reviews and longer reviews at Amazon.com; (2) an improvement in a book's reviews leads to an increase in relative sales at that site; (3) for most samples in the study, the impact of one-star reviews is greater than the impact of five-star reviews; and (4) evidence from review-length data suggests that customers read review text rather than relying only on summary statistics.

Abstract: I NCENTIVES ARE the essence of economics. Despite many wide-ranging claims about their supposed importance, there has been little empirical assessment of incentive provision for workers. The purpose of this paper is to critically overview existing work on the provision of incentives. Since the interests of workers and their employers are not always aligned, a large theoretical literature has emphasized how firms design compensation contracts to induce employees to operate in the firm's interest. This literature has reached into many areas of compensation and has pointed to a multitude of different mechanisms that can be used to induce workers to act in the interests of their employers. These include piece rates, options, discretionary bonuses, promotions, profit sharing, efficiency wages, deferred compensation, and so on. My objective here is to evaluate this literature in the light of a growing empirical literature on compensation. Where possible, I will address the literature from two perspectives. First, an underlying assumption of this literature is that individuals respond to contracts that reward performance. Accordingly, I consider whether agents behave in this way, and whether these responses are always in the firm's interest. Second, I address whether firms write contracts with these responses in mind. In other words, do contracts look like the predictions of the theory? Incentives are provided to workers

Abstract: We investigate conditions sufficient for identification of average treatment effects using instrumental variables. First we show that the existence of valid instruments is not sufficient to identify any meaningful average treatment effect. We then establish that the combination of an instrument and a condition on the relation between the instrument and the participation status is sufficient for identification of a local average treatment effect for those who can be induced to change their participation status by changing the value of the instrument. Finally we derive the probability limit of the standard IV estimator under these conditions. It is seen to be a weighted average of local average treatment effects.