A New Foundation for the Propensity Interpretation of Fitness

The propensity interpretation of fitness (PIF) is commonly taken to be subject to a set of simple counterexamples. We argue that three of the most important of these are not counterexamples to the PIF itself, but only to the traditional mathematical model of this propensity: fitness as expected number of offspring. They fail to demonstrate that a new mathematical model of the PIF could not succeed where this older model fails. We then propose a new formalization of the PIF that avoids these (and other) counterexamples. By producing a counterexample-free model of the PIF, we call into question one of the primary motivations for adopting the statisticalist interpretation of fitness. In addition, this new model has the benefit of being more closely allied with contemporary mathematical biology than the traditional model of the PIF

Risk Sharing and the Tax System

Several papers have documented that US consumers can not fully insure themselves against all their idiosyncratic risks, but little is understood about which mechanisms provide insurance. We investigate whether, as some suggest, progressive taxes provide additional insurance. The methodology distinguishes insurance from redistribution, and can by applied to testing any potential insurance mechanism. Using repeated cross-sections from the US consumer expenditure survey (CEX), we relate changes in consumption inequality to several measures of tax progressivity. Identification exploits the variation in taxes both across states and over time. Our results suggest, under weak assumptions, that progressive taxes do not induce insurance, while stronger assumptions quantify this effect.

Informal Credit Markets, Judicial Costs and Consumer Credit: Evidence from Firm Level Data

How does the punishment for default affect repayment behavior? We use administrative data provided by the leading Italian lender of unsecured credit to the household sector to investigate the effect of two potentially important factors: judicial efficiency and the availability of informal credit from family and friends. By making economic assumptions we can place upper and lower bounds on these effects. We find that the availability of informal credit reduces repayment, while variation in court enforcement has no significant effect. Moreover, households with access to informal credit are more likely to borrow from our lenderHouseholds Borrowing, Informal Credit Markets, Asymmetric Information

Bounds on repayment behavior: evidence for the consumer credit market

How does the punishment for default affect repayment behavior? We use administrative data, provided by the leading Italian lender of unsecured credit to the household sector, to analyze households repayment behavior. Administrative data are particularly well suited to study what factors are responsible for default, but raise a fundamental econometric problem, since they identify the determinants of repayment behavior only for those who are granted credit. To overcome this problem, we provide upper and lower bounds on the determinants of repayment behavior. Moreover, we show how to use the restrictions from the theory to narrow the bounds.Manski Bounds, Consumer Credit, Default

Housing and equity wealth effects of Italian households

The study quantifies stock market and housing market wealth effects on households' non-durable consumption using Italian household panel data (SHIW) of 1989-2002. We found all households react similarly to aggregate housing and stock market gains. We also found statistically and economically significant housing wealth effects with a marginal propensity to consume out of idiosyncratic housing wealth gains to be over 8 percent. The results from idiosyncratic equity wealth e¤ects were lower, at around 0.4 percent. We also found that older households react more to changes in housing wealth. JEL Classification: D12, E21Equities, housing, Marginal Propensity to Consume

Resource Price Turbulence and Macroeconomic Adjustment for a Resource Exporter: a conceptual framework for policy analysis

Increased global demand for energy and other resources, particularly from the rapidly developing economies of China and India and the opening up of global resource markets to global investors and speculative activity, has resulted in considerable recent turbulence in resource prices. The recent magnitude of change in resource prices, both positive and negative, and their macroeconomic implications is of considerable contemporary importance to both resource importing and exporting economies. For a resource exporting economy, such as that of Australia, the recent resource price boom has resulted in: increased government taxation revenue, increased employment and wages in the resource and resource related sectors, increased spending in the domestic economy that contributed to buoyant economic growth, increased resource exports to the booming economies of China and India and contributed to a stronger domestic currency with beneficial effects upon inflation. On the other hand these developments have had adverse effects on the non resource sector by: subjecting it to more intense competition for limited resources, contributing to a loss of international competitiveness and reduced exports arising from a stronger exchange rate, reducing employment in the relatively more labour intensive non resource sector, and contributing to an eventual slow down in the overall economy. These positive and negative effects, and the overall impact of a resource price boom, require a fundamentally closer analysis of the structure of the economy under scrutiny. In this context the policy response by government is likely to be pivotal in determining the overall macroeconomic outcomes from a resource price boom. The aim of this paper is to develop a generic analytical framework to appraise economic outcomes in the wake of a resource price boom for a resource producing and exporting economy. To this end a dynamic long run macroeconomic model is developed, emphasising the important role and contribution of government fiscal policy in influencing subsequent macroeconomic outcomes. The adjustment process in the model arising from a resource price shock emphasises a spending (or wealth) effect, an income effect, a revenue effect, a current account effect and an exchange rate effect, which facilitate a robust analysis of subsequent macroeconomic outcomes from such a shock as well as related policy responses.Resource price shock, dynamic macroeconomic model, simulation analysis, macroeconomic adjustment, policy analysis

Evidence on the Insurance Effect of Marginal Income Taxes

Marginal income taxes may have an insurance effect by decreasing the effective fluctuations of after-tax individual income. By compressing the idiosyncratic component o personal income fluctuations, higher marginal taxes should be negatively correlated with the dispersion of consumption across households, a necessary implication of an insurance effect of taxation. Our study empirically examines this negative correlation, exploiting the ample variation of state taxes across US states. We show that taxes are negatively correlated with the consumption dispersion of the within-state distribution of non-durable consumption and that this correlation is robust.Undiversifiable Earnings Risk, Consumption Insurance, Tax Distortions

Evidence on the Insurance Effect of Redistributive Taxation

If households face uninsurable idiosyncratic earnings risk, theory predicts that redistributive tax and transfer systems have both an insurance and a distortionary effect. Exploiting the substantial variation of tax and transfer systems across US states we investigate the necessary traces of these two effects in the data: that state-level measures of redistributive taxation should correlate negatively with, (a) the standard deviation, and (b) the mean, of the within-state consumption distribution. We find that the first correlation is robust, supporting strongly the presence of an insurance effect. The distortionary effect can also be detected in the data but it is less precisely estimated.Undiversi¯able Earnings Risk, Consumption Insurance, Tax Distortions

Evidence on the Insurance Effect of Redistributive Taxation

A distinguishing feature among households is whether adult members work or not, since the occupational status of adults affects their available time for home activities. Using a survey method in two countries, Belgium and Germany, we provide household incomes that retain the level of well-being across different family types, distinguished by family size and occupational status of adults. Our tests support that childcare-time costs are important determinants of household well-being. Estimates of child costs relative to an adult are higher for households that are time-constrained (all adults in the household work). Moreover, we find supportive evidence for the hypothesis that, in two-adult households, there is a potential for within-household welfare gains from specialization in market- vs. domestic activities, especially childcare.