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1.
The paper describes non‐parametric approach for analysis of a three‐period, two‐treatment, four‐sequence crossover design in which test procedure for interchangeability of the treatment effects is obtained. The proposed procedure is based on a non‐parametric model, which incorporates, along with the direct treatment effects and the usual carryover effects, the long‐term carryover effects. Relevant competitors are obtained. Related asymptotic results are given. By performing simulation study, we compared the procedures with respect to type I error rate and power. Furthermore, confidence intervals for treatment differences are studied. The procedures are illustrated with a data study.  相似文献   

2.
In treatment effect analysis, there are many cases where the treatment of interest is ordered (e.g. general‐education years or medicine doses) and the control treatment is not zero, but a different type of treatment (a vocational training or a surgery). We develop an approach to find effects of partly ordered treatments, while correcting for possible treatment endogeneity with nearly parametric control functions. We use this control function approach, along with its supplementary version, to estimate effects of military ranks (ordered treatments) on wage relative to non‐veteran status (control treatment) with the Wisconsin Longitudinal Study data. In our empirical analysis, the military rank effects differ much: officer has large positive effects, but enlisted ranks have small or no effects.  相似文献   

3.
In this paper, we propose several finite‐sample specification tests for multivariate linear regressions (MLR). We focus on tests for serial dependence and ARCH effects with possibly non‐Gaussian errors. The tests are based on properly standardized multivariate residuals to ensure invariance to error covariances. The procedures proposed provide: (i) exact variants of standard multivariate portmanteau tests for serial correlation as well as ARCH effects, and (ii) exact versions of the diagnostics presented by Shanken ( 1990 ) which are based on combining univariate specification tests. Specifically, we combine tests across equations using a Monte Carlo (MC) test method so that Bonferroni‐type bounds can be avoided. The procedures considered are evaluated in a simulation experiment: the latter shows that standard asymptotic procedures suffer from serious size problems, while the MC tests suggested display excellent size and power properties, even when the sample size is small relative to the number of equations, with normal or Student‐t errors. The tests proposed are applied to the Fama–French three‐factor model. Our findings suggest that the i.i.d. error assumption provides an acceptable working framework once we allow for non‐Gaussian errors within 5‐year sub‐periods, whereas temporal instabilities clearly plague the full‐sample dataset. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

4.
In this study the effects of various types of rehabilitation programmes on labour market outcomes are estimated. A main feature of this study is that it jointly evaluates multiple treatments by nonparametric matching estimators. The study is based on a large sample of persons in western Sweden who are long‐term sick and could participate in rehabilitation programmes. Our results suggest that workplace training is superior to the other rehabilitation programmes with respect to labour market outcomes, but compared to non‐participation no positive effects are found. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

5.
This paper estimates a dynamic ordered probit model of self‐assessed health with two fixed effects: one in the linear index equation and one in the cut‐points. This robustly controls for heterogeneity in unobserved health status and in reporting behavior, although we cannot separate both sources of heterogeneity. We find important state dependence effects, and small but significant effects of income and other socioeconomic variables. Having dynamics and flexibly accounting for unobserved heterogeneity matters for those estimates. We also contribute to the bias correction literature in nonlinear panel models by comparing and applying two of the existing proposals to our model. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

6.
We review three alternative approaches to modelling survey non‐contact and refusal: multinomial, sequential, and sample selection (bivariate probit) models. We then propose a multilevel extension of the sample selection model to allow for both interviewer effects and dependency between non‐contact and refusal rates at the household and interviewer level. All methods are applied and compared in an analysis of household non‐response in the United Kingdom, using a data set with unusually rich information on both respondents and non‐respondents from six major surveys. After controlling for household characteristics, there is little evidence of residual correlation between the unobserved characteristics affecting non‐contact and refusal propensities at either the household or the interviewer level. We also find that the estimated coefficients of the multinomial and sequential models are surprisingly similar, which further investigation via a simulation study suggests is due to non‐contact and refusal having largely different predictors.  相似文献   

7.
A Bayesian method for outlier‐robust estimation of multinomial choice models is presented. The method can be used for both correlated as well as uncorrelated choice alternatives and guarantees robustness towards outliers in the dependent and independent variables. To account for outliers in the response direction, the fat‐tailed multivariate Laplace distribution is used. Leverage points are handled via a shrinkage procedure. A simulation study shows that estimation of the model parameters is less influenced by outliers compared to non‐robust alternatives. An analysis of margarine scanner data shows how our method can be used for better pricing decisions. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

8.
The present paper introduces a methodology for the semiparametric or non‐parametric two‐sample equivalence problem when the effects are specified by statistical functionals. The mean relative risk functional of two populations is given by the average of the time‐dependent risk. This functional is a meaningful non‐parametric quantity, which is invariant under strictly monotone transformations of the data. In the case of proportional hazard models, the functional determines just the proportional hazard risk factor. It is shown that an equivalence test of the type of the two‐sample Savage rank test is appropriate for this functional. Under proportional hazards, this test can be carried out as an exact level α test. It also works quite well under other semiparametric models. Similar results are presented for a Wilcoxon rank‐sum test for equivalence based on the Mann–Whitney functional given by the relative treatment effect.  相似文献   

9.
We experimentally investigate behavior in sequential one‐shot transactions which are governed by non‐binding contracts. In a second, incomplete information treatment, contracts are binding for some players. While according to traditional game‐theoretical analysis no trade is expected in the first treatment, full trade should result in the latter. However, we find that trade is even higher in the non‐binding contract treatment. On the one hand, non‐binding contracts—although they are cheap talk—do guide behavior, especially at the beginning of a business relationship, while reciprocal reactions prevail later on. On the other hand, in the treatment with binding contracts cooperative behavior appears to be crowded out. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

10.
In the context of multiple treatments for a particular problem or disorder, it is important theoretically and clinically to investigate whether any one treatment is more effective than another. Typically researchers report the results of the comparison of two treatments, and the meta-analytic problem is to synthesize the various comparisons of two treatments to test the omnibus null hypothesis that the true differences of all particular pairs of treatments are zero versus the alternative that there is at least one true nonzero difference. Two tests, one proposed by Wampold et al. (Psychol. Bull. 122:203–215, 1997) based on the homogeneity of effects, and one proposed here based on the distribution of the absolute value of the effects, were investigated. Based on a Monte Carlo simulation, both tests adequately maintained nominal error rates, and both demonstrated adequate power, although the Wampold test was slightly more powerful for non-uniform alternatives. The error rates and power were essentially unchanged in the presence of random effects. The tests were illustrated with a reanalysis of two published meta-analyses (psychotherapy and antidepressants). It is concluded that both tests are viable for testing the omnibus null hypothesis of no treatment differences.  相似文献   

11.
This research analyzes the non‐cooperative and cooperative strategies with respect to manufacturer and retailer coupons. In a model with one manufacturer selling its product to one retailer, it is found that the retailer can achieve third‐degree price discrimination equilibrium in retail markets by issuing coupons to demanders with higher elasticity. Although facing only one retailer, the manufacturer can also achieve the same third‐degree price discrimination equilibrium by issuing coupons directly to demanders of higher elasticity. However, when only one firm issues the coupon, both manufacturer and retailer coupons can help alleviate the channel profit loss due to double marginalization. If the manufacturer and the retailer non‐cooperatively issue coupons, then the subgame‐perfect Nash equilibrium outcomes are equivalent to those under the successive third‐degree price discrimination. Moreover, cooperative strategies between the manufacturer and the retailer can eliminate double marginalization, achieve the vertical integration effect, and lead to higher profits, consumer surpluses, and social surpluses than non‐cooperative coupon strategies. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

12.
In this paper, we experimentally investigate the impact of costly indirect and direct messages on coordination levels in a stag‐hunt game. Three main insights emerge from our experiments. First, we find a significant decrease in message usage with message cost in both treatments and a higher decrease in the indirect‐message treatment. Second, we find that although there is no significant effect of costless or costly indirect messages on the frequency of risky actions, both costless, and costly direct messages significantly increase the frequency of risky actions. Third, while we find a significant increase in the coordination rate on the payoff‐dominant equilibrium from costless indirect message treatment to costly indirect message treatment, this rate significantly decreases from costless direct message to costly direct message treatment. Our findings show that depending on the structure of messages, message cost may increase or decrease the coordination rates on the payoff‐dominant equilibrium with respect to costless communication. However, costly communication increases efficient coordination rates with respect to the no communication baseline. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

13.
In this paper we propose a simulation‐based technique to investigate the finite sample performance of likelihood ratio (LR) tests for the nonlinear restrictions that arise when a class of forward‐looking (FL) models typically used in monetary policy analysis is evaluated with vector autoregressive (VAR) models. We consider ‘one‐shot’ tests to evaluate the FL model under the rational expectations hypothesis and sequences of tests obtained under the adaptive learning hypothesis. The analysis is based on a comparison between the unrestricted and restricted VAR likelihoods, and the p‐values associated with the LR test statistics are computed by Monte Carlo simulation. We also address the case where the variables of the FL model can be approximated as non‐stationary cointegrated processes. Application to the ‘hybrid’ New Keynesian Phillips Curve (NKPC) in the euro area shows that (i) the forward‐looking component of inflation dynamics is much larger than the backward‐looking component and (ii) the sequence of restrictions implied by the cointegrated NKPC under learning dynamics is not rejected over the monitoring period 1984–2005. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

14.
In this paper we discuss the analysis of data from population‐based case‐control studies when there is appreciable non‐response. We develop a class of estimating equations that are relatively easy to implement. For some important special cases, we also provide efficient semi‐parametric maximum‐likelihood methods. We compare the methods in a simulation study based on data from the Women's Cardiovascular Health Study discussed in Arbogast et al. (Estimating incidence rates from population‐based case‐control studies in the presence of non‐respondents, Biometrical Journal 44, 227–239, 2002).  相似文献   

15.
Using a large panel of mainly unquoted euro‐area firms over the period 2003–2011, this paper examines the impact of financial pressure on firms’ employment. The analysis finds evidence that financial pressure negatively affects firms’ employment decisions. This effect is stronger during the euro area‐crisis (2010–2011), especially for firms in the periphery compared to their counterparts in non‐periphery European economies. When we introduce firm‐level heterogeneity, we show that financial pressure appears to be both statistically and quantitatively more important for bank‐dependent, small and privately held firms operating in periphery economies during the crisis.  相似文献   

16.
Identification in most sample selection models depends on the independence of the regressors and the error terms conditional on the selection probability. All quantile and mean functions are parallel in these models; this implies that quantile estimators cannot reveal any—per assumption non‐existing—heterogeneity. Quantile estimators are nevertheless useful for testing the conditional independence assumption because they are consistent under the null hypothesis. We propose tests of the Kolmogorov–Smirnov type based on the conditional quantile regression process. Monte Carlo simulations show that their size is satisfactory and their power sufficient to detect deviations under plausible data‐generating processes. We apply our procedures to female wage data from the 2011 Current Population Survey and show that homogeneity is clearly rejected. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

17.
In this research we explore how local amenities relate to proprietorship growth by merging two lines of work: amenities and rural growth and the drivers of proprietorship and small business growth. We do so to examine what role, if any, different types of amenties play in promoting the growth of small businesses in rural USA. Using data for rural US counties we explore the role of natural and built amenities in the growth of rural non‐farm proprietorships between 2000 and 2008 by employing a spatial Durbin model to account for both spatial dependency in the data and to explicitly model spatial spillover effects. The results offer evidence that proprietorship growth is spatially clustered, spatial spillover effects matter, and proprietorship growth is higher in those areas with particular climate attributes. That is, the effect of climate on quality of life may be enough to attract individuals who wish to start new firms.  相似文献   

18.
This paper argues that the assumption of strict exogeneity, which is usually invoked in estimating models of state dependence with unobserved heterogeneity, is violated in the poverty context as important variables determining contemporaneous poverty status, in particular employment status and household composition, are likely to be influenced by past poverty outcomes. Therefore, a model of state dependence is developed that explicitly allows for possible feedback effects from past poverty to future employment and household composition outcomes. Empirical results based on data from the German Socio‐Economic Panel (GSOEP) suggest that there are indeed such feedback effects and that failure to take them into account may lead to biased estimates of the state dependence effect. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

19.
This paper uses official Italian micro data and different methods to estimate, in the framework of potential outcomes, the marginal return to college education allowing for heterogeneous returns and for self-selection into higher education. Specifically, the paper is focused on the estimation of heterogeneity of average treatment effect (ATE) on a cohort of college and high school graduates using the 2008 survey on household, income and wealth of the Bank of Italy. Methodologically, this study was carried out by using both propensity-score-based (PS-based) methods and a new approach based on marginal treatment effects (MTE), recently proposed by Heckman and his associates as a useful strategy when the ignorability assumption may be violated. In the PS-based approach, heterogeneous treatment effects are estimated in three different manners: the traditional stratification approach (propensity score strata), the regression adjustment within propensity score strata and, finally, a non-parametric smoothing approach. In the MTE approach, the treatment effect heterogeneity across individuals is estimated in a parametric as well as a semi-parametric strategy. Our empirical analysis shows that the estimated heterogeneity is substantial: following MTE based results (quite representative of other methods) the return to college graduation for a randomly selected individual varies from as high as 20 % (for persons who would add one fifth of wage from graduating college) to as low as ?22 % (for persons who would lose from college graduation), suggesting that returns are higher for individuals more likely to attend college. Furthermore, the results of different methods show very low (point) estimates of ATE: average college returns vary from 3.5 % by the PS-smoothing method to 1.8 % by the parametric MTE method, which also leads a greater treatment effect on treated (5.5 %), a moderate, but significant sorting gain and a negligible selection bias.  相似文献   

20.
The so‐called “new growth theory” is characterized by the now Nobel Prize winning insight that ideas are a nonrival input to and output from endogenous investment in innovation. Nonrivalry implies increasing returns to scale, but this also unintentionally creates an empirically disputed scale effect that a growing population implies an ever‐increasing growth rate. Empirical evidence supports fully‐endogenous growth without scale effects, but theoretical issues sustain the decades‐long dispute over exactly how to negate the scale effect. This article surveys theoretical approaches to resolving the scale effect and shows how four generations of endogenous growth theory are defined by the maturing of modeling techniques for constraining increasing returns. The synthesis suggests that the dispute over scale effects is really a narrative about how the powerful application of increasing returns has followed a standard theoretical development pattern. This implies that a fourth generation is now emerging that negates the scale effect while retaining fully‐endogenous growth without relying on assumptions of linearity. Instead, the market response to excessive increasing returns to innovation constrains explosive growth by expanding the market, rather than by a linear assumption. This latest class of endogenous growth models may be the final chapter to resolving the long‐running dispute.  相似文献   

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