Effect of finger interaction on individual finger: index finger

Grip strength is affected by such as enslaving effect, force sharing effect, and force deficit effect relating to the interaction among fingers. The author attempts to analyze index finger strength according to grip span of adjacent middle finger. 6 male graduate students participated as subjects in this experiment. The grip span has been applied from 45 mm to 60mm to investigate the effects of a coordination of grip spans on the index and middle finger strength. Results showed that index finger strength was the smallest in case of index finger grip span of 45 mm. Index finger strength decreased as the middle finger grip span. In general index finger strength shared a decreasing trend when the grip span of the middle finger increased. This study has an implication that the grip span of index and middle fingers influences force sharing effect on index finger.     

A new algorithm for maximum likelihood estimation in normal scale-mixture generalized autoregressive conditional heteroskedastic models

In this paper, we propose a new generalized autoregressive conditional heteroskedastic (GARCH) model using infinite normal scale-mixtures which can suitably avoid order selection problems in the application of finite normal scale-mixtures. We discuss its theoretical properties and develop a two-stage algorithm for the maximum likelihood estimator to estimate the mixing distribution non-parametric maximum likelihood estimator (NPMLE) as well as GARCH parameters (two-stage MLE). For the estimation of a mixing distribution, we employ a fast computational algorithm proposed by Wang [On fast computation of the non-parametric maximum likelihood estimate of a mixing distribution. J R Stat Soc Ser B. 2007;69:185–198] under the gradient characterization of the non-parametric mixture likelihood. The GARCH parameters are then estimated either using the expectation-mazimization algorithm or general optimization scheme. In addition, we propose a new forecasting algorithm of value-at-risk (VaR) using the two-stage MLE and the NPMLE. Through a simulation study and real data analysis, we compare the performance of the two-stage MLE with the existing ones including quasi-maximum likelihood estimator based on the standard normal density and the finite normal mixture quasi maximum estimated-likelihood estimator (cf. Lee S, Lee T. Inference for Box–Cox transformed threshold GARCH models with nuisance parameters. Scand J Stat. 2012;39:568–589) in terms of the relative efficiency and accuracy of VaR forecasting.     

On the conservative simultaneous confidence procedures for multiple comparisons among mean vectors

In this paper, conservative simultaneous confidence intervals for multiple comparisons among mean vectors in multivariate normal distributions are considered. Some properties of the multivariate Tukey–Kramer procedure for pairwise comparisons and the conservative simultaneous confidence procedure for comparisons with a control are presented. Particularly, the upper bound for the conservativeness of the simultaneous confidence procedure for comparisons with a control is obtained. Finally, numerical results by Monte Carlo simulations and an example to illustrate the procedure are given.     

Inference for the two-parameter half-logistic distribution using pivotal quantities under progressively Type-II censoring schemes

This article addresses estimation and prediction problems for the two-parameter half-logistic distribution based on pivotal quantities when a sample is available from the progressively Type-II censoring scheme. An unbiased estimator of the location parameter based on a pivotal quantity is derived. To estimate the scale parameter, a new method based on a pivotal quantity is proposed. The proposed method provides a simpler estimation equation than the maximum likelihood equation. In addition, confidence intervals for the location and scale parameters are derived from these pivotal quantities. In the prediction of censored failure times, the shortest-length predictive intervals for the censored failure times are derived using a pivotal quantity. Finally, the validity of the proposed method is assessed through Monte Carlo simulations and a real data set is presented for illustration purposes.     

Is There a Jump in the Transition?

This article develops a statistical test for the presence of a jump in an otherwise smooth transition process. In this testing, the null model is a threshold regression and the alternative model is a smooth transition model. We propose a quasi-Gaussian likelihood ratio statistic and provide its asymptotic distribution, which is defined as the maximum of a two parameter Gaussian process with a nonzero bias term. Asymptotic critical values can be tabulated and depend on the transition function employed. A simulation method to compute empirical critical values is also developed. Finite-sample performance of the test is assessed via Monte Carlo simulations. The test is applied to investigate the dynamics of racial segregation within cities across the United States.     

Ambiguity and Second‐Order Belief

Anscombe and Aumann (1963) wrote a classic characterization of subjective expected utility theory. This paper employs the same domain for preference and a closely related (but weaker) set of axioms to characterize preferences that use second‐order beliefs (beliefs over probability measures). Such preferences are of interest because they accommodate Ellsberg‐type behavior.     

Robust Bayesian analysis for exponential parameters under generalized Type-II progressive hybrid censoring

The Type-II progressive hybrid censoring scheme has received wide attention, but it has a disadvantage in that long time may be required to complete the life test. The generalized progressive Type-II hybrid censoring scheme has recently been proposed to solve this problem. Under the censoring scheme, the time on test does not exceed a predetermined time. In this paper, we propose a robust Bayesian approach based on a hierarchical structure when the generalized progressive Type-II hybrid censored sample has a two-parameter exponential distribution. For unknown parameters, marginal posterior distributions are provided in closed forms, and their statistical properties are discussed. To examine the robustness of the proposed method, Monte Carlo simulations are conducted and a real data set is analyzed. Further, the quality and adequacy of the proposed model are evaluated in an analysis based on the real data.     

On Test Statistics in Profile Analysis with High-dimensional Data

We consider profile analysis with unequal covariance matrices under multivariate normality. In particular, we discuss this problem for high-dimensional data where the dimension is larger than the sample size. We propose three test statistics based on Bennett’s (1951) transformation and the Dempster trace criterion proposed by Dempster (1958 Dempster, A.P. (1958). A high dimensional two samples significance test. Annals of Mathematical Statistics 29:995–1010.[Crossref] , [Google Scholar]). We derive the null distributions as well as the nonnull distributions of the test statistics. Finally, in order to investigate the accuracy of the proposed statistics, we perform Monte Carlo simulations for some selected values of parameters.     

SUR Approach for IV Estimation of Canonical Contagion Models

Seemingly unrelated regression (SUR) method is applied to the instrumental variable (IV) estimation of the canonical contagion models. A finite sample Monte Carlo experiment shows that the resulting estimator, IV-SUR estimator, is substantially better than the existing IV estimator in terms of both bias and mean squares error under diverse circumstance of instrument, conditional heteroscedasticity, and cross-section correlation.     

The interactive effect of leader–member exchange and electronic communication on employee psychological empowerment and work outcomes

We advance understanding of the role that leaders play in promoting psychological empowerment and positive work outcomes (job satisfaction, organizational commitment and job performance) for employees who engage in a high degree of electronic communication in their job. By integrating leader–member exchange (LMX) theory and theories of electronic communication, we build and test a mediated moderation model in which employees’ degree of electronic communication in their job amplifies the positive relationship that LMX has to psychological empowerment and subsequent employee work outcomes. Based on a sample of 353 early-career professionals employed in a range of different types of organizations, we found general support for the hypothesized model. We discuss the study’s theoretical and practical implications for leading employees in electronically-enabled work environments.