Knowledge that Transforms

Departures from self-interest in economic experiments have recently inspired models of “social preferences”. We design a range of simple experimental games that test these theories more directly than existing experiments. Our experiments show that subjects are more concerned with increasing social welfare—sacrificing to increase the payoffs for all recipients, especially low-payoff recipients—than with reducing differences in payoffs (as supposed in recent models). Subjects are also motivated by reciprocity: They withdraw willingness to sacrifice to achieve a fair outcome when others are

This paper presents an interpretation of rising regionalism in world trade as a coordination failure, based on (i) sector-specific sunk costs in production, and (ii) "friction" in trade negotiation. Given these elements, if a regional trade bloc is expected to form, private agents will make investments that will make bloc member countries more specialized toward each other, but bloc and nonbloc countries mutually less specialized. This diminishes the ex post demand for multilateral free trade. Thus, the expected supply of regionalism generates its own demand, creating a Pareto-inferior equilibrium.

This research develops an evolutionary growth theory that captures the interplay between the evolution of mankind and economic growth since the emergence of the human species. This uni…ed theory encompasses the observed evolution of population, technology and income per capita in the long transition from an epoch of Malthusian stagnation to sustained economic growth. The theory suggests that prolonged economic stagnation prior to the transition to sustained growth stimulated natural selection that shaped the evolution of the human species, whereas the evolution of the human species was the origin of the take-o¤ from an epoch of stagnation to sustained growth. – Growth ; Technological Progress ; Fertility ; Human Capital ; Evolution ; Natural Selection ; Malthusian Stagnation

It is well-known that if international linkages are relatively small, the potential gains to international monetary policy coordination are typically quite limited. But when goods and financial markets are tightly linked, is it problematic if countries unilaterally design their monetary policy rules? Are the stabilization gains from having separate currencies largely squandered in the absence of effective international monetary coordination? We argue that under plausible assumptions the answer is no. Unless risk aversion is very high, lack of coordination in rule setting is a second-order problem compared with the overall gains from macroeconomic stabilization.

Sex ratios, i.e., relative numbers of men and women, can affect marriage prospects, labor force participation, and other social and economic variables. But the observed association between sex ratios and social and economic conditions may be confounded by omitted variables and reverse causality. This paper uses variation in immigrant flows as a natural experiment to study the effect of sex ratios on the children and grandchildren of immigrants. The flow of immigrants affected the second generation marriage market because second generation marriages were mostly endogamous, i.e., to members of the same ethnic group. The empirical results suggest that high sex ratios had a large positive effect on the likelihood of female marriage, and a large negative effect on female labor force participation. Perhaps surprisingly, the marriage rates of second generation men appear to be a slightly increasing function of immigrant sex ratios. Higher sex ratios also appear to have raised male earnings and the incomes of parents with young children. The empirical results are broadly consistent with theories where higher sex ratios increase female bargaining power in the marriage market.

Countries differ significantly in the way in which they regulate the entry of new businesses. To meet government requirements for starting to operate a business in Austria, an entrepreneur must complete 12 procedures taking at least 154 business days and pay US$11,612 in government fees. To do the same, an entrepreneur in Bolivia needs to follow 20 different procedures, pay US$2,696 in fees to the government and wait at least 82 business days to acquire the necessary permits. In contrast, an entrepreneur in Canada can finish the process in roughly 2 days by paying US$280 in government fees and completing only 2 procedures.

Common currencies affect trading costs and, thereby, the amounts of trade, output, and consumption. From the perspective of monetary policy, the adoption of another country's currency trades off the benefits of commitment to price stability (if a committed anchor is selected) against the loss of an independent stabilization policy. We show that the type of country that has more to gain from giving up its own currency is a small open economy heavily trading with one particular large partner, with a history of high inflation and with a business cycle highly correlated with that of the potential “anchor.” We also characterize the features of the optimal number of currency unions.

This paper investigates individual motives to participate in rotating savings and credit associations (roscas). Detailed evidence from roscas in a Kenyan slum (Nairobi) suggests that most roscas are predominantly composed of women, particularly those living in a couple and earning an independent income. We propose an explanation of this based on conflictual interactions within the household. Participation in a rosea is a strategy a wife employs to protect her savings against claims by her husband for immediate consumption. The empirical implications of the model are then tested using the data collected in Kenya.

This paper analyzes monotone comparative statics predictions in several classes of stochastic optimization problems. The main results characterize necessary and sufficient conditions for comparative statics predictions to hold based on properties of primitive functions, that is, utility functions and probability distributions. The results apply when the primitives satisfy one of the following two properties: (i) a single-crossing property, which arises in applications such as portfolio investment problems and auctions, or (ii) log-supermodularity, which arises in the analysis of demand functions, affiliated random variables, stochastic orders, and orders over risk aversion.

Many people believe in the "Law of Small Numbers," exaggerating the degree to which a small sample resembles the population from which it is drawn. To model this, I assume that a person exaggerates the likelihood that a short sequence of i.i.d. signals resembles the long-run rate at which those signals are generated. Such a person believes in the "gambler's fallacy", thinking early draws of one signal increase the odds of next drawing other signals. When uncertain about the rate, the person over-infers from short sequences of signals, and is prone to think the rate is more extreme than it is. When the person makes inferences about the frequency at which rates are generated by different sources --- such as the distribution of talent among financial analysts --- based on few observations from each source, he tends to exaggerate how much variance there is in the rates. Hence, the model predicts that people may pay for financial advice from "experts" whose expertise is entirely ...