Sample Selection Correction in Panel Data Models When Selectivity Is Due to Two Sources

This paper proposes a specification of Wooldridge's (1995) two step estimation method in which selectivity bias is due to two sources rather than one. The main objective of the paper is to show how the method can be applied in practise. The application concerns an important problem in health economics: the presence of asymmetric information in the private health insurance markets on which there exists a large literature. The data for the empirical application is drawn from the 2003/2004 Medical Expenditure Panel Survey in conjunction with the 2002 National Health Interview Survey.multiple sample selection bias; panel data; asymmetric information.

Correlation established between heat transfer and ultrasonic transmission properties of copper braze bonds

Measuring and correlating the thermal conductivity and ultrasonic transmission of seven hot-brazed-bonded copper plates established a relationship between heat transfer and ultrasonic transmission properties of the bonds. This relationship permits the prediction of heat transfer characteristics from ultrasonic transmission tests

An Economic Evaluation of Life-Style and Air-pollution-related Damages: Results from the BRFSS

This paper uses the Behavioral Risk Factor Surveillance System (2001) data in conjunctions with Environmental Protection Agency data to investigate on how individual health habits, air outdoor pollution and diseases combine to affect the likelihood of good health status and the amount of health investments. The environment is a second-best world characterized by uncertainty on the level of health, in which individuals are not able to avoid health shocks completely. Models are estimated using three different measures of overall health: a measure of self-assessed health and two health outcomes indicators (blood pressure and activity limitations due to health problems).Health production, multivariate probit, life-style, pollution, self-assessed health, health outcome

Sample selection correction in panel data models when selectivity is due to two sources

This paper proposes a specification of Wooldridge's (1995) two step estimation method in which selectivity bias is due to two sources rather than one. The main objective of the paper is to show how the method can be applied in practice. The application concerns an important problem in health economics: the presence of adverse selection in the private health insurance markets on which there exists a large literature. The data for the empirical application is drawn from the 2003/2004 Medical Expenditure Panel Survey in conjunction with the 2002 National Health Interview Survey.

From theory to implementation of the best instrument to protect human health: a brief overview

This paper presents a survey of methods of regulations with focus on pollution abatement and of various approaches to the issue of measuring quantities such as the marginal benefit of improved health that are crucial in view of implementing the regulation. Since pollution is a public bad, in general the efficient level of pollution can only be reached by way of some sort of public intervention. The paper's focus is on so-called marketbased mechanisms, which in turn are classified into price-based mechanisms (pollution taxes) and quantity-based mechanisms (tradeable permits). The basic framework for addressing the comparison between the two types of mechanisms is Weitzman (1974). In order to actually choose between regulation methods and to eventually implement chosen methods, estimates are needed of some crucial quantities, in particular of marginal costs and benefits of pollution abatement. The most problematic one is of course marginal benefit. Therefore the paper considers various approaches to the measurement of marginal benefits.marginal costs, marginal benefits, pollution regulation, health

Adverse selection in the U.S. health insurance markets: Evidence from the MEPS

We use the 2003/2004 Medical Expenditure Panel Survey in conjunctions with the 2002 National Health Interview Survey to test for adverse selection in the U.S. private health insurance market. The key idea is to test whether the individuals who are more exposed to health risks also buy insurance contracts with more coverage or higher expected payments. The critical statistical problem is that the extension of insurance is only measured for those who are insured and face positive health care expenditure. So there is a possible sample selection bias effect. The procedure used is based on a method suggested by Wooldridge (1995). The method also accounts for heterogeneity across individuals. The simultaneous account taken of both possible sources of bias is new for this kind of application.adverse selection, health insurance, risk profile

Regolazione dei prezzi o razionamento: l'efficacia dei due sistemi di allocazione nella fornitura di risorse scarse a coloro che ne hanno maggiore necessita'..

Usando un semplice modello formale, dovuto a Martin Weitzman, questo paper analizza sotto quali condizioni il sistema dei prezzi sia piu' efficace del sistema di razionamento, nel fornire un determinato bene, presente in quantita'  scarsa, a coloro che ne hanno una maggiore necessita' , in presenza di informazione incompleta. La risposta dipende dalla distribuzione dei bisogni e dalla distribuzione del reddito. Il sistema dei prezzi gode di un grande vantaggio comparato, nel fornire un bene scarso e nel raggiungere i piu' bisognosi, quando nella societa'  la distribuzione dei bisogni e' molto dispersa e la distribuzione del reddito e' pressoche' egalitaria. Invece, il razionamento risulta essere piu' efficace quando i bisogni sono uniformi ma vi e' una forte ineguaglianza nella distribuzione del reddito. Rielaborando tale modello, inoltre, e' possibile dimostrare che in presenza di una funzione cubica di perdita di efficacia, il vantaggio comparato di un sistema sull'altro dipende dall'asimmetria della distribuzione del reddito. Si mostra, infine, come il meccanismo di razionamento mediante coda possa rappresentare una possibile soluzione al problema dell'informazione incompleta..

The indirect effect of fine particulate matter on health through individuals' life-style

Limited literature has been published on the association between environmental health indicators, life-style habits and ambient air pollution. We have examined the association of asthma prevalence and the amount of health investment with daily mean concentrations of particulate matter (PM) with a mass median aerodynamic diameter less than 2.5 mm (PM2.5) in 16 metropolitan areas in U.S. using the Behavioral Risk Factor Surveillance System (2001) data in conjunction with the Air Quality System data collected by the Environmental Protection Agency. A multivariate probit approach has been used to estimate recursive systems of equations for environmental health outcomeand life-styles. A piecewise linear relationship has been postulated to describe the association between health outcome, health investment and pollution using the procedure mkspline from STATA 10. This model has allowed for fitting a "breakpoint" in the probit functions. We have assumed one change point at AQI value of 100 which corresponds to the US national air quality standard. The most interesting result concerns the influence of pollution on health-improving life-style choices: below a specified threshold concentration (AQI=100) a positive linear association exists between exposure to PM2.5 and health investments; above the threshold the association becomes negative. Hence, only if ambient pollution is in the 'satisfactory range' (AQI level at or below 100), individuals will have incentive to invest in health.health production, multivariate probit, mkspline, lifestyle, fine particulate, asthma

Smoking inequality across genders and socio-economic positions. Evidence from Italian data

There has been a dearth of literature on smoking inequalities, in spite of its contribution to health inequalities. We exploit Italian individual-level data from repeated cross-sections of the annual household survey, “Aspects of Daily Life,” that was part of the Multipurpose Survey carried out by the Italian National Statistical Office (ISTAT) for the period 1999–2012 to identify the main socio-demographic characteristics that determine smoking inequalities. We use the Concentration Index to identify in which groups smoking is relatively more prevalent. We find that, among men, pro-rich inequality is driven by members of the lower socio-economic positions, while we observe the opposite for women. We encourage policymakers to address the issue of smoking inequalities, which the current policies have largely disregarded