8 resultados para testing against heavy tails
em Scottish Institute for Research in Economics (SIRE) (SIRE), United Kingdom
Resumo:
We develop tests of the proportional hazards assumption, with respect to a continuous covariate, in the presence of unobserved heterogeneity with unknown distribution at the individual observation level. The proposed tests are specially powerful against ordered alternatives useful for modeling non-proportional hazards situations. By contrast to the case when the heterogeneity distribution is known up to …nite dimensional parameters, the null hypothesis for the current problem is similar to a test for absence of covariate dependence. However, the two testing problems di¤er in the nature of relevant alternative hypotheses. We develop tests for both the problems against ordered alternatives. Small sample performance and an application to real data highlight the usefulness of the framework and methodology.
Resumo:
We report experiments designed to test between Nash equilibria that are stable and unstable under learning. The “TASP” (Time Average of the Shapley Polygon) gives a precise prediction about what happens when there is divergence from equilibrium under fictitious play like learning processes. We use two 4 x 4 games each with a unique mixed Nash equilibrium; one is stable and one is unstable under learning. Both games are versions of Rock-Paper-Scissors with the addition of a fourth strategy, Dumb. Nash equilibrium places a weight of 1/2 on Dumb in both games, but the TASP places no weight on Dumb when the equilibrium is unstable. We also vary the level of monetary payoffs with higher payoffs predicted to increase instability. We find that the high payoff unstable treatment differs from the others. Frequency of Dumb is lower and play is further from Nash than in the other treatments. That is, we find support for the comparative statics prediction of learning theory, although the frequency of Dumb is substantially greater than zero in the unstable treatments.
Resumo:
We propose a nonlinear heterogeneous panel unit root test for testing the null hypothesis of unit-roots processes against the alternative that allows a proportion of units to be generated by globally stationary ESTAR processes and a remaining non-zero proportion to be generated by unit root processes. The proposed test is simple to implement and accommodates cross sectional dependence. We show that the distribution of the test statistic is free of nuisance parameters as (N, T) −! 1. Monte Carlo simulation shows that our test holds correct size and under the hypothesis that data are generated by globally stationary ESTAR processes has a better power than the recent test proposed in Pesaran [2007]. Various applications are provided.
Resumo:
With salaries subjected to scrutiny more than ever, it is increasingly important that the process by which they are determined be understood and justifiable. Both public and private organisations now routinely rely on so-called “job evaluation” as a means of constructing an appropriate pay-scale and as such it is ever more necessary that we appreciate how this system works and that we recognise its limits. Only with such an understanding of the way in which salaries are set can we hope to have a meaningful discussion of their economic function. This paper aims to expound the details of job evaluation both in theory and in practice, and critically assess its shortcomings. In Section 1 below we describe the job evaluation system and in Section 2 we briefly outline the history and the usage of the system in both the private and the public sector. In Section 3 we theoretically analyse the often unstated but nonetheless implicit assumptions made by practitioners of the art of job evaluation. Section 4 applies the analysis of Section 3 to review a particular and important case study, namely The Senior Salaries Review of the Welsh Assembly 2004. Section 5 concludes.
Resumo:
In this paper we challenge the conventional view that strikes are caused by asymmetric information regarding rm profitability such that union members are uninformed. Instead, we build an expressive model of strikes where the perception of unfairness provides the expressive benefi t of voting for a strike. The model predicts that larger union size increases both wage offers and the incidence of strikes. Furthermore, while asymmetric information is still important in causing strikes, we find that it is the employer who is not fully informed about the level of emotionality within the union, thereby contributing to strike incidence. An empirical test using UK data provides support for the predictions. In particular, union size has a positive effect on the incidence of strikes and other industrial actions even when asymmetric information regarding profitability is controlled for.
Resumo:
In this paper we challenge the conventional view that strikes are caused by asymmetric information regarding firm protability such that union members are uninformed. Instead, we build an expressive model of strikes where the perception of unfairness provides the expressive benefit of voting for a strike. The model predicts that larger union size increases both wage offers and the incidence of strikes. Furthermore, while asymmetric information is still important in causing strikes, we find that it is the employer who is not fully informed about the level of emotionality within the union, thereby contributing to strike incidence. An empirical test using UK data provides support for the predictions. In particular, union size has a positive effect on the incidence of strikes and other industrial actions even when asymmetric information regarding protability is controlled for.
Resumo:
In contrast to previous results combining all ages we find positive effects of comparison income on happiness for the under 45s, and negative effects for those over 45. In the BHPS these coefficients are several times the magnitude of own income effects. In GSOEP they cancel to give no effect of effect of comparison income on life satisfaction in the whole sample, when controlling for fixed effects, and time-in-panel, and with flexible, age-group dummies. The residual age-happiness relationship is hump-shaped in all three countries. Results are consistent with a simple life cycle model of relative income under uncertainty.
Resumo:
Genuine Savings has emerged as a widely-used indicator of sustainable development. In this paper, we use long-term data stretching back to 1870 to undertake empirical tests of the relationship between Genuine Savings (GS) and future well-being for three countries: Britain, the USA and Germany. Our tests are based on an underlying theoretical relationship between GS and changes in the present value of future consumption. Based on both single country and panel results, we find evidence supporting the existence of a cointegrating (long run equilibrium) relationship between GS and future well-being, and fail to reject the basic theoretical result on the relationship between these two macroeconomic variables. This provides some support for the GS measure of weak sustainability. We also show the effects of modelling shocks, such as World War Two and the Great Depression.