A Graphical Tool for Interpreting Regression Coefficients of Trinomial Logit Models

Multinomial logit (also termed multi-logit) models permit the analysis of the statistical relation between a categorical response variable and a set of explicative variables (called covariates or regressors). Although multinomial logit is widely used in both the social and economic sciences, the interpretation of regression coefficients may be tricky, as the effect of covariates on the probability distribution of the response variable is nonconstant and difficult to quantify. The ternary plots illustrated in this article aim at facilitating the interpretation of regression coefficients and permit the effect of covariates (either singularly or jointly considered) on the probability distribution of the dependent variable to be quantified. Ternary plots can be drawn both for ordered and for unordered categorical dependent variables, when the number of possible outcomes equals three (trinomial response variable); these plots allow not only to represent the covariate effects over the whole parameter space of the dependent variable but also to compare the covariate effects of any given individual profile. The method is illustrated and discussed through analysis of a dataset concerning the transition of master’s graduates of the University of Trento (Italy) from university to employment.     

区块链技术在版权登记中的创新应用

随着数字版权时代的发展，作品的传播方式变得更加灵活，传播速度也更加迅捷。传统版权登记制度因存在登记成本较高、标准不一、泄露隐私等弊端，在实际应用中面临困境，区块链技术的出现为推动版权登记的适时发展提供了一种新思路。区块链技术应用于版权登记，其去中心化特质可以降低登记成本；分布式共享机制能够统一登记标准；难以篡改的性质能够提高登记的证明效力；弥补了既有版权登记制度的缺陷。同时，区块链技术利用自身特性建立新的版权信任机制，既能清晰地分配版权利益，又能创新传统的版权商业模式，推动版权市场的发展，最大化地利用版权的固有价值。区块链技术在与版权登记相结合的过程中，会出现一些技术上难以解决的问题，既无法对作品的独创性进行准确的判断，也无法发挥版权制度原有的公示力作用。因此，必须创新版权登记规则，加快制定区块链版权平台市场准入机制，并设置统一的监管机构，将区块链锁在版权制度的笼子里，防止出现滥用区块链技术的情形，以最终实现技术和法律的融合发展。     

试论投资基金的治理结构

投资基金的治理结构包含三个层次,即基金的各方当事人权利义务的制度安排、基金内部约束机制、外部市场压力及监管制度。针对我国基金治理结构目前存在的问题,可通过引入独立董事制度、将基金经理的报酬机制与公司的经营业绩挂钩、增强外部市场的竞争压力等途径,使之逐步完善。     

Parental Divorce and Interpersonal Trust in Adult Offspring

It has been proposed that recent increases in parental divorce have inhibited the development of trust among offspring. This proposition is tested by examining whether parental divorce is associated with offspring trust in parents, intimate partners, and others. Data come from the Marital Instability Over the Life Course Study. Results reveal that although parental divorce is negatively associated with trust, these effects largely disappear once the quality of the past parent‐teen relationship is taken into account. The one exception is trust in fathers where children of divorce remain at higher risk of mistrust. Trust in parents, intimates, and others is strongly linked to positive parent‐teen relationships regardless of parental divorce. Contemporary relationship experiences also influence trusting intimates and others.     

GMM tests for the Katz family of distributions

Generalized method of moments (GMM) is used to develop tests for discriminating discrete distributions among the two-parameter family of Katz distributions. Relationships involving moments are exploited to obtain identifying and over-identifying restrictions. The asymptotic relative efficiencies of tests based on GMM are analyzed using the local power approach and the approximate Bahadur efficiency. The paper also gives results of Monte Carlo experiments designed to check the validity of the theoretical findings and to shed light on the small sample properties of the proposed tests. Extensions of the results to compound Poisson alternative hypotheses are discussed.     

Robust testing with generalized partial linear models for longitudinal data

By approximating the nonparametric component using a regression spline in generalized partial linear models (GPLM), robust generalized estimating equations (GEE), involving bounded score function and leverage-based weighting function, can be used to estimate the regression parameters in GPLM robustly for longitudinal data or clustered data. In this paper, score test statistics are proposed for testing the regression parameters with robustness, and their asymptotic distributions under the null hypothesis and a class of local alternative hypotheses are studied. The proposed score tests reply on the estimation of a smaller model without the testing parameters involved, and perform well in the simulation studies and real data analysis conducted in this paper.     

Quadratic estimators of covariance components in a multivariate mixed linear model

It is known that the Henderson Method III (Biometrics 9:226–252, 1953) is of special interest for the mixed linear models because the estimators of the variance components are unaffected by the parameters of the fixed factor (or factors). This article deals with generalizations and minor extensions of the results obtained for the univariate linear models. A MANOVA mixed model is presented in a convenient form and the covariance components estimators are given on finite dimensional linear spaces. The results use both the usual parametric representations and the coordinate-free approach of Kruskal (Ann Math Statist 39:70–75, 1968) and Eaton (Ann Math Statist 41:528–538, 1970). The normal equations are generalized and it is given a necessary and sufficient condition for the existence of quadratic unbiased estimators for covariance components in the considered model.     

信任关系的不完全信息动态博弈模型

以往理论研究与经验研究均指出"信任"关系具有外部效应,但对这种效应是怎样取得的并无共识.我们尝试建立一个不完全信息动态博弈模型,说明"信任"关系如何产生正的外部性,亦即产生超出个体理性计算之外的利益.我们的分析得出这样的结论,在一个多人互动的环境中,能否达到彼此信任,虽然会受到欺骗者所遭到的惩罚与欺骗利益多少的影响,但主要受到所处环境中具有信任者人数比例的影响.因此,可以说"信任"关系具有正的外部性,信任者人数越多,信任者所享受到的利益越大.     

Local influence in multilevel models

The authors study the local influence of observations in multilevel regression models. To this end, they perturb simultaneously the variances, responses and design matrix. To measure the local change caused by these perturbations, they use generalized Cook statistics for the fixed and random parameter estimates. Closed form local influence measures also allow them to assess the joint influence of various observations. They suggest a simple computation method and illustrate their results using two examples.