Uniform minimum variance unbiased estimators for bivariate families

Summary We consider uniform minimum variance unbiased (UMVU) estimation of an unbiased estimable function of distribution parameters for bivariate truncation (non-regular) parameter families. In particular, we derive the UMVU estimator of the probability thatY is less thanX.     

A note on Model Reference Adaptive System (MRAS) estimate with infinite variance

This paper discusses the estimation of a parameter in an autoregressive model with infinite variance. A recursive estimation procedure based on minimizing the prediction errors is provided. It is also shown that the model reference adaptive system estimate for an AR (1) model given in Aase (1983) is a special case.     

A note on estimation of variance components in a multi-stage sampling design based on interpenetrating sub-samples

Summary In this note it is shown that unbiased estimators of the components of the sampling variance of an estimator in the case of a stratified multi-stage sampling design could easily be obtained by selecting the samples at the different stages in the form of two or more independent interpenetrating sub-samples.     

A note on the equivalence of specification tests in the two-factor multivariate variance components model

This note offers a generalization of Hausman and Taylor's equivalence of specification tests in the single-equation variance (error) components model to the two-factor multivariate variance components case. The relationship between the specification tests and the hypothesis test in the model proposed by Mundlak is also discussed.     

A test for the weights of the global minimum variance portfolio in an elliptical model

In this paper we consider the weights of the global minimum variance portfolio (GMVP). The returns are assumed to follow a matrix elliptically contoured distribution, i.e., the returns are assumed to be neither independent nor normally distributed. A test for the general linear hypothesis is given. The distribution of the test statistic is derived under the null and the alternative hypothesis. It turns out that its distribution is invariant with respect to the type of the matrix elliptical distribution, i.e., the stochastic properties of the GMVP do not depend either on the mean vector or on the distributional assumptions imposed on asset returns. In an empirical study we analyze an international diversified portfolio.     

Optimality of balanced designs for minimum norm quadratic unbiased estimation of variance components

This paper develops an approximate theory for the optimality of balanced designs under minimum norm quadratic unbiased estimation of variance components in one-way classified data.     

The finite-sample effects of VAR dimensions on OLS bias,OLS variance,and minimum MSE estimators

Vector autoregressions (VARs) are important tools in time series analysis. However, relatively little is known about the finite-sample behaviour of parameter estimators. We address this issue, by investigating ordinary least squares (OLS) estimators given a data generating process that is a purely nonstationary first-order VAR. Specifically, we use Monte Carlo simulation and numerical optimisation to derive response surfaces for OLS bias and variance, in terms of VAR dimensions, given correct specification and several types of over-parameterisation of the model: we include a constant, and a constant and trend, and introduce excess lags. We then examine the correction factors that are required for the least squares estimator to attain the minimum mean squared error (MSE). Our results improve and extend one of the main finite-sample multivariate analytical bias results of Abadir, Hadri and Tzavalis [Abadir, K.M., Hadri, K., Tzavalis, E., 1999. The influence of VAR dimensions on estimator biases. Econometrica 67, 163–181], generalise the univariate variance and MSE findings of Abadir [Abadir, K.M., 1995. Unbiased estimation as a solution to testing for random walks. Economics Letters 47, 263–268] to the multivariate setting, and complement various asymptotic studies.     

A note on redistribution

A consequence of income redistribution may well be to make everyone (including lower-income groups to which redistribution takes place) worse off after a period of years. Possibly income redistribution might gain consent because of risk aversion. The paper also draws attention to the tendency for people to be more concerned about poverty close at hand rather than far away.     

A note on linked bargaining

A recent result by Jackson and Sonnenschein (2007) describes a general framework for overcoming incentive constraints by linking together independent copies of a Bayesian decision problem. A special case of that work shows that if copies of a standard two-player Bayesian bargaining problem are independently linked (players receive valuations and trade simultaneously on a number of identical copies), then the utility cost associated with incentive constraints tends to 0 as the number of linked problems tends to infinity. We improve upon that result, increasing the rate of convergence from polynomial to exponential and eliminating unwanted trades in the limit, by introducing a mechanism that uses a slightly richer and more refined strategy space. Although very much in the same spirit, our declarations are constrained by a distribution which is skewed away from the expected distribution of player types. When a sufficiently large number of bargaining problems are linked, “truth” is an equilibrium. Moreover, this equilibrium is incentive compatible with the utility cost of incentive constraints almost surely equal to 0.     

A note on a heteroscedastic model

In this article the author considers a regression model where the variance of the error term is a linear combination of certain independent variables and compares four different estimators of the coefficients of this linear combination, They are (1) the estimator proposed by Goldfeld and Quant and called the Modified Glejser Method, (2) the estimator proposed by Hildreth and Houck, (3) the generalized least squares method, and (4) the maximum likelihood estimator. It is shown that the first two are asymptotically not fully efficient whereas the last two are.     

A note on fourth-order risk aversion

Keenan et al. (J Risk Uncertain 24:264–277, 2002) introduced a measure of downside risk aversion (third-order risk aversion), and in Theorem 1, they showed four equivalent definitions of increased downside risk aversion. This result is thought as a higher-order extension of Theorem 3 in Diamond et al. (J Econ Theory 8:337–360, 1974). We consider fourth-order risk aversion and show four equivalent definitions of increased fourth-order risk aversion. Our result is thought as a higher-order extension of Theorem 1 in Keenan et al. (2002).     

A note on component-wise kronecker designs

Summary The paper investigates the particular case of symmetrical block designs with block size two. It is shown that the component-wise Kronecker product of two such designs (c.f. Mukerjee 1981) is connected if and only if the numbers of treatments are relatively prime.     

A note on testing demand homogeneity

In this note we establish the relationship among the three test statistics for testing demand homogeneity and comment on the relative merits of these statistics.     

A note on health care inflation

A key issue in health care reform is the need to contain the inflation rate of the CPI for health care services without substantially reducing the quality of health care. Althought the previous literature has widely debated the causes of increasing inflation in the CPI for health care services, very little has been done to empirically test these arguments. We use an econometric framework that allows us to expressly examine the determinants of the inflation rate of the CPI for health care services. The data cover the period from 1960–1994. The main results provide empirical verification for many of the demand-side and supply-side theories of the inflation rate of the CPI for health care services that have been widely discussed in the literature.     

A note on local pareto optima

This note gives an elementary proof of the sufficient second order conditions for a local Pareto optimum.     

A note on quasi convex programming

The function % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9

$$f(x) = \frac{{x'B x + c' x + \alpha }}{{D' x + \beta }}$$     

A note on mixed Poisson approximation

Conditions sufficient for the weak convergence of sums of 0–1 random variables indexed by k -sets to a mixed Poisson law are presented. An example of applications concerning "distance" random variables is also provided.     

A note on pro-poor social expenditures

This study extended the concept of ‘pro-poor growth’ in terms of social expenditures that measure whether social expenditures are pro-poor or not pro-poor. Using the idea of pro-poor growth, this study examines as to what extent the poor benefited from the growth of social expenditures i.e., human development, rural development, safety nets and community services. The monotonicity axiom sets out a condition that the proportional reduction in poverty is a monotonically increasing function of the pro-poor growth. This study satisfies the monotonicity criterion relative with social expenditures and proposes a ‘poverty equivalent social expenditure rate’, which takes into account both the magnitude of social expenditures growth and how the benefits of these expenditures are distributed to the poors and the non-poors. This methodology is applied to Pakistan’s unit record household surveys during the periods of 1964–2011 (21 household surveys) and examines the interrelationship between social expenditures, inequality, and poverty. It is argued that the satisfaction of a monotonicity axiom is a key criterion for measuring pro-poor growth. The results found that the social expenditures in Pakistan are not intrinsically pro poor. Although it was strongly pro poor in the 1980s and pro poor in the 1990s, growth in the 1970s and 2000s was anti poor, if the poverty related social expenditures still remains anti-poor in the subsequent years as reflected in the years 2008–2011, there is a likelihood that these expenditures may not trickle down to the poor but instead to the non-poor. It is indicative that to achieve rapid poverty reduction, the poverty equivalent growth rate ought to be maximized rather than the actual growth rate of social expenditures in Pakistan.     

A note on defining geographic markets

This paper offers an approach to delineating geographic markets and/or product markets based on the notion of instantaneous causality. After providing a brief review of the issue of concern and a discussion of the relevant statistical methodology the flour market in the United States is examined. It is concluded that the flour market in fact is national in scope.