台湾储蓄互助社规模与成长之研究——Gibrat＇s Law应用

本文系探讨台湾储蓄互助社规模与成长间关系有否符合吉尔伯特法则（Gibrat＇s Law）,利用1996年至2007年储互社纵横资料（panel data）分析台湾310家储蓄互助社的资产总额、社员人数及教育支出等变数。经由Levin,Lin＆Chu及IPS单根检定结果发现,台湾储互社规模变量皆拒绝虚无假设,且呈现定态不具有单根的现象,此显示出台湾储蓄互助社规模与其成长实际上具有关联性,隐含了储互社成长没有随机漫步现象也不符合吉尔伯特法则,表示台湾储互社长期无需集中扩大增加其规模。     

Social security and firm performance: The case of Vietnamese SMEs

This article investigates how social security provision – a key determinant of formality – impacts on small and medium‐sized firm performance in Viet Nam. Based on enterprise census data covering all registered firms from 2006 to 2011, the authors find that firms which increase their social security coverage by 10 per cent experience a revenue gain of 1.4–2.0 per cent per worker and a profit gain of up to 1.8 per cent, depending on the survival time of the firm. However, given the time lag between “investment” (in social security contributions) and returns (enhanced firm performance), specific policy measures such as initial social insurance subsidies for small firms could increase participation in mandatory schemes.     

Normal Mixture Quasi-maximum Likelihood Estimator for GARCH Models

Abstract.  The generalized autoregressive conditional heteroscedastic (GARCH) model has been popular in the analysis of financial time series data with high volatility. Conventionally, the parameter estimation in GARCH models has been performed based on the Gaussian quasi-maximum likelihood. However, when the innovation terms have either heavy-tailed or skewed distributions, the quasi-maximum likelihood estimator (QMLE) does not function well. In order to remedy this defect, we propose the normal mixture QMLE (NM-QMLE), which is obtained from the normal mixture quasi-likelihood, and demonstrate that the NM-QMLE is consistent and asymptotically normal. Finally, we present simulation results and a real data analysis in order to illustrate our findings.     

Bias Reduction of Likelihood Estimators in Semiparametric Frailty Models

Abstract. Frailty models with a non‐parametric baseline hazard are widely used for the analysis of survival data. However, their maximum likelihood estimators can be substantially biased in finite samples, because the number of nuisance parameters associated with the baseline hazard increases with the sample size. The penalized partial likelihood based on a first‐order Laplace approximation still has non‐negligible bias. However, the second‐order Laplace approximation to a modified marginal likelihood for a bias reduction is infeasible because of the presence of too many complicated terms. In this article, we find adequate modifications of these likelihood‐based methods by using the hierarchical likelihood.     

The impact of critical success factors of JIT implementation on organizational performance

Much has been written and publicized about the virtues of JIT philosophies during the past decade. However, relatively limited empirical research has been reported con-cerningJIT implementation on organizational performance. This study presents the results of an empirical study which utilized both concrete financial accounting data and a broad cross-sectional survey as measures of organizational performance to determine the impact of each JIT implementation requirement factor to organizational performance. Communication between production and marketing departments was identified as a critical factor for increased inventory turnover and work-in-process inventory turnover, while employees' participation and the bottom-up management approach were determined as significant factors for improving quality and flexibility. The results of this study imply that in JTT environment personnel management practices, such as bottom-up management encouraging employees participation, and organization management such as a communications linking the production and marketing departments, are more important than JIT practices themselves.     

Heterogeneous dispatching rules in job and flow shops

This paper reports the results of a study of the use of heterogeneous dispatching rules for the scheduling of work in a job shop. The methodology employed included discrete event simulation, using rule combinations determined by prior genetic algorithm searches and generalization using neural networks. Eight dispatching rules were considered, including first in first out (FIFO), earliest due date ( EDD), shortest processing time (SPT), slack/ number of operations (SLK), critical ratio (CR), modified due date (MDD), modified operation due date (MOD), and apparent tardiness cost (ATC). A three-machine job shop was studied, in which three work organizations were employed, pure flow (fixed sequence), pure job shop ( random sequence), and a hybrid shop where flow is random but with unequal probabilities. Three levels of machine loading were used and average tardiness was used as the performance measure. In most cases, modified due date and apparent tardiness cost were the best rules. The application of the best rules effected the results primarily when applied to bottleneck machines or the first machine in a pure flow shop. Nearly any other rule was acceptable on non-botdeneck machines except FIFO and CR, which consistently perform poorly. No major advantage of mixing rules was found.     

Presidential Popularityand Presidential Elections

Current Research This section of POQ is reserved for brief reportsof research in progress, discussions of unresolved problems,methodological studies, and public opinion data not extensivelyanalyzed or interpreted. Succinct case histories are welcomed,as well as hypotheses and insights that may be useful to otherstudents of public opinion. Usually, materialin this sectionis shorter, more informal, and more tentative than in precedingpages.     

RATIONING BY SELLER'S PREFERENCE AND PACIAL PRICE DISCRIMINATION

This paper investigates the behavior of a seller who has a preference for a certain group of customers. The seller maintains stable prices over time and supplements price rationing with a nonprice rationing. In this situation the preferred buyers would have priority over nonpreferred buyers in purchasing the commodity, and if the latter purchase the commodity they may be paying higher prices. It is proposed here that the premium paid by the nonpreferred buyers is a necessary bribe to induce the seller to forego his search for the preferred buyers.