A comparison of bias approximations for the two-stage least squares (2SLS) estimator

We consider the bias of the two-stage least squares (2SLS) estimator in linear instrumental variable regression with only one endogenous regressor. By using asymptotic expansion techniques, we approximate the 2SLS coefficient estimation bias under various scenarios regarding the number and strength of instruments.     

Consumer Welfare and the Livestock Economy in the United States

This paper analyzes the responsiveness of the U.S. meal and poultry economy to government policies and other exogenous shocks. In particular, it focuses on the measurement of changes to consumer welfare. An explicit econometric model represents the supply of fed beef, non-fed beef, pork, and poultry. The interaction between the livestock and feed grain markets is captured by an econometric model of the supply and demand for corn. Consumers are represented by a complete system of consumer demand equations. The model is used for a partial analysis of the welfare effects of an actual agricultural policy decision – the sale of large quantities of grains to the Soviet Union in the third quarter of 1972. The loss to consumers that is attributable to the increased grain exports did not reach its maximum until the second quarter of 1975. It is estimated that from 1973 to 1975 consumers suffered a reduction of meat consumption that they valued at $4.5 billion (U.S.). Furthermore, the effects of grain exports proved far larger than the losses due to the poor harvests of 1973 and 1974. Finally, attempts to shelter consumers from the effects of the increased corn exports, either by increased beef imports or increased grain price supports, would have had little success in compensating for the welfare loss actually suffered. Ce papier fail ?analvse de la réponse des secleurs de ?économie quant au bétail et à la volatile aux Flats-Unis, leur reponse à la politique gouvernementale et à?aulres coups exterieurs. En particulier, ce papier se concentre sur la mésure des changements au bien-étre des consommateurs. Un modèle économélrique qui est explicite représente ?approvisionnement du boeuf brouiè, du boeuf non-broutè, du pore el de la volatile. Lcar;action réciproque entre le marché de bélail et ie marché de grains est monlré par un modèle economelrique de ?offre et de la demande pour mats. Un système des équations représente la demande des consommateurs. On utilise le modèle pour ohtenir une analyse parlielle des effeis en ce qui concerne le bien-étre des consommateurs par suite ?une décision faite ?une politique agricole – celle de la vente de grandes quantités de grains à?Union soviétique au troisième quartier de ?année 1972. Laperte aux consommateurs qui est imputable aux exportations augmentées de grain n'apas alteinl son maximum jusqu'au deuxième quartier de 1975. On a eslimé que de 1973 à 1975 les consommateurs ont essuyé une réduction de la consommation de viande qu'ils ont evaluée à$4.5 milliard (en dollars des Etats-Unis). En outre, les effeis des exponations de grain se sont révélés bien grands que les effets des moissons maigres de 1973 el 1974. Finalement, des efforts de protéger les consommateurs contre les effets des exportations augmentees de maìs, ou par des importations augmentees de boeufou par augmenter le soutien pour le prix du grain auraient eu peu de succès à remplacer les pertes en fait essuyées.     

Can a Mixed Health Care System be Desirable on Equity Grounds?*

Should health care provision be public, private, or both? We consider this question in a setting where people differ in their earnings capacity and face some illness risk. We assume that illness reduces an individual's time endowment when waiting for treatment. Treatment can be obtained in a competitive private sector (through private insurance) or in the National Health Service (NHS) where it is provided free of charge but after some (endogenous) waiting time. The equilibrium in the health care sector consists of a waiting time in the NHS such that no patient wants to switch health care provider. This equilibrium is governed by two public policies: the income tax system and the size of the NHS. We find that: (i) a mixed system with a small NHS is never desirable; (ii) actuarially fair sickness insurance is never desirable either; (iii) a mixed system with a sufficiently large NHS may improve on a pure public system if the dispersion of earnings capacities is large enough; and (iv) the welfare gains from such a mixed system are not likely to be significant.     

Home Equity Conversion Instruments with Fixed Term to Maturity: Alternatives to End of Term Pay-Off

Standard reverse annuity mortgages obligate the lender to take on the risk that an elderly homeowner will desire to remain in a residence after the RAM has reached maturity. In this case, the best the lender can hope for is that the property will have appreciated sufficiently that the loan can be carried at interest only. There is a possibility for lender loss but not gain over contracted return.
Alternatives to the standard RAM are explored in this paper with most attention devoted to shared appreciation and shared equity RAMs. These alternative instruments appear to solve the problem of maturity risk.     

Labor Mobility, Trade, and Social Capital

Labor market integration raises welfare in the absence of distortions. This paper examines labor and goods market integration in a general‐equilibrium model with social capital. The findings are: (i) labor market integration has an ambiguous impact on welfare, and raises it if the goods and labor skills are sufficiently different; (ii) compared to Pareto optimum, labor mobility (social capital) is excessively large (depleted); (iii) trade is superior to labor market integration if trading costs are no higher than private migration costs, otherwise the outcome is ambiguous; and (iv) the creation of new institutions in response to labor market integration has an ambiguous impact on welfare.     

The Valuation of Semiannual Bonds between Interest Payment Dates: A Correction

This note provides a correction to Taylor's 1988 work on the valuation of semiannual coupon bonds between interest payment dates. It shows that the discrepancy in values between Taylor's model and the standard Wall Street pricing formula is much smaller than indicated by Taylor and is unlikely to generate opportunities for arbitrage profits.     

Sur une loi de probabilité considérée par J. F. Steffensen

Abstract

Dans ce même périodique, vous avez considéré¹, à la page 7, la loi de probabilité de deux variables aléatoires X, Y,² où la probabilité élémentaire ?(x, y) dx dy pour que X et Y soient respectivement compris entre x et x + dx, y et y + dy, est de la forme où K, a ₁, a ₂, b ₁, b ₂ sont des constantes. Nous nous proposons, dans ce qui suit, d'apporter quelques compléments à votre exposé.