• International Journal of Quality Innovation
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• v.7 no.1
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• pp.206-222
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• 2006

Recent research on quality management systemically explored the use of quality management practices and performance. The consequences of using quality practices have not been consistently confirmed despite an increasing number of published empirical studies. The results of empirical studies of quality practices and performance are mixed. This study examines which quality management practices indicate high-, medium-, and low-performance under the TQM framework using MANOVA and multiple discriminant analysis (MDA). To measure quality management practices, this study used the Malcolm Baldrige National Quality Award (MBNQA) framework. Based on a survey of 490 suppliers from eleven different industries in Korea, the results revealed that the high performing group surpasses the medium and low performing groups in process management, employee empowerment, employee education and training, and employee satisfaction. Furthermore, the high and medium performing groups exceed the low performing group in human resource planning and evaluation, strategic deployment, leadership system, and senior executive leadership.

• Journal of the Korean GEO-environmental Society
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• v.9 no.7
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• pp.53-60
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• 2008

The purpose of this study is to make case studies on estimation of shear wave velocity in core zone of some rockfill dams by MASW (Multi-channel Analysis of Surface Waves) and to compare the results of case studies with those of the empirical method. Furthermore, the purpose is to recommend the range of shear wave velocity in core zone by MASW and to supply the preliminary data for estimation of shear wave velocity in core zone which is needed for dynamic analysis. From the results of case studies and the comparison between the results of case studies and those of empirical equation, it was found that the shear wave velocities obtained by MASW were smaller than those by the empirical recommendation (Sawada & Takahashi) in the depth of more than 10 m. Also, it is recommended that using the lower bound of empirical formulation by Sawada and Takahashi be available and resonable in case that MASW is not available due to the field condition and the investigation is preliminary.

• Journal of the Korean Home Economics Association
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• v.36 no.11
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• pp.209-218
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• 1998

The purpose of this study was to conduct the review of female labor suply, and thus, to provide useful theoretical and empirical frameworks for future studies related to female labor supply. Based on the theory of the allocation of time, the process of individual labor supply was systematically reviewed. Participation Probit/Logit, Tobit, and Selection B;ias Corrected Regression were considered in estimating the function of female labor supply which modifies the selection bias. Based on the previous empirical results, wage rate, asset income, husband's income, the level of eduction, and child-related variables such as the presence of child and the number of children might be considered for the empirical specification of female labor supply.

• The Journal of Information Technology
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• v.2 no.1
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• pp.15-34
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• 1999

The purpose of this paper is to survey existing literature and empirical studies about the effect of unions on productivity and productivity growth in US and British. Evidence regarding union effects on productivity is incomplete in the studies surveyed in this paper. Unions have a positive effect on productivity in US, but the most of studies in British show that unions have a negative effect. But the direction and magnitude of union effects on productivity growth cannot be predicted from economic theory. It may be that there is no unitary relationship between unions and productivity growth. The comprehensive conclusion about the effects of unions on productivity growth cannot be drawn from the studies surveyed in this paper. The question of whether unions have a positive effect or negative effect on productivity and productivity growth is an empirical issue.

• International Journal of Highway Engineering
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• v.17 no.1
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• pp.119-127
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• 2015

PURPOSES : Before-and-after studies of red light cameras were conducted with the aim of reducing the number of side right-angle collisions. Three different methods were used for the before-and-after studies, and the analysis results were compared. METHODS : This research used the naive before-and-after method, the comparison-group method, and the empirical Bayes method to study the effects of red light cameras on side-angle collisions. The results of the three before-and-after methods were compared and interpreted in terms of safety indications at signalized intersections. RESULTS : The research results showed that side right-angle collisions can be reduced by installing red light cameras at signalized intersections. All three methods guarantee safety improvements of 25~30% on average. With regard to the results of each method, the naive before-and-after method, the comparison-group method, and the empirical Bayes method showed safety improvements of 25.6%, 27.8%, and 29.7%, respectively. CONCLUSIONS : It was concluded that red light cameras are an effective countermeasure to improve intersection safety. In particular, by installing red light cameras, side right-angle collisions can be reduced by up to approximately 25~30%.

• Communications for Statistical Applications and Methods
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• v.27 no.5
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• pp.547-568
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• 2020

Modeling the statistical autocorrelations in spatial data is often achieved through the estimation of the variograms, where the selection of the appropriate valid variogram model, especially for small samples, is crucial for achieving precise spatial prediction results from kriging interpolations. To estimate such a variogram, we traditionally start by computing the empirical variogram (traditional Matheron or robust Cressie-Hawkins or kernel-based nonparametric approaches). In this article, we conduct numerical studies comparing the performance of these empirical variograms. In most situations, the nonparametric empirical variable nearest-neighbor (VNN) showed better performance than its competitors (Matheron, Cressie-Hawkins, and Nadaraya-Watson). The analysis of the spatial groundwater dataset used in this article suggests that the wave variogram model, with hole effect structure, fitted to the empirical VNN variogram is the most appropriate choice. This selected variogram is used with the ordinary kriging model to produce the predicted pollution map of the nitrate concentrations in groundwater dataset.

• Korean Management Science Review
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• v.34 no.3
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• pp.61-77
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• 2017

This study investigates the effect of consumer involvement in the relationship between customer satisfaction and loyalty (which is measured as consumers' repurchase and WOM intentions). Previous research has presented inconsistent implications on the role of consumer involvement in the relationship. Some researchers have presented the empirical results showing that consumer involvement moderates the relationship, whereas others have done the empirical results implying that the consumer involvement does not moderates. In sum, the previous empirical studies have provided the inconsistent empirical results that consumer involvement may be a moderator or a non-moderator in the relationship between customer satisfaction and loyalty. Thus, we start this research with two research questions: "Does consumer involvement has a moderation effect on the relationship between-customer satisfaction and loyalty across various service industries?" and "Can the moderation effect of consumer involvement be detected differently depending on the statistical methods used to probe the moderation effect?" A questionnaire survey was conducted in the context of four service categories: eight service firms for fast food, four firms for family restaurant, four firms for movie theater and four firms for Bakery. Hierarchical regression analyses (moderated regression analyses) and chi-square difference tests were used to identify the role of consumer involvement in the relationship between customer satisfaction and loyalty. The empirical results show that there does not exist the difference in the moderation effects of consumer involvement identified by the two statistical methods (i.e., hierarchical regression analyses vs. chi-square difference tests), however, that there exists the difference in the identified moderation effects of consumer across service categories. In the final section, we summarize the implications and re-interpret the empirical results provided in the previous studies.

• English Language & Literature Teaching
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• v.15 no.4
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• pp.55-74
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• 2009

Although a considerable amount of research on discourse signaling cues has been conducted in reading, little attention has been paid to such cues in the area of listening. Moreover, despite the solid evidence showing that cues have beneficial effects for reading comprehension, L2 listening research has produced mixed findings about the role of cues. Such discrepancies among these findings might be due in part to inadequate research methodologies as well as the idiosyncratic features of their experimental designs. However, no study, to date, has thoroughly examined the research designs of listening comprehension studies on cues. Consequently, this study critically evaluates the present state of research designs and reporting practices of studies investigating the role of cues in listening comprehension. The present study aims to provide insights into areas that require empirical attention and systematic investigation. It also seeks to encourage improved and refined research practices for future studies. This paper is organized as follows: It will first critically review the empirical findings regarding cues in the area of L1 listening comprehension. Second, it will present a critical evaluation of L2 listening studies on cues. Finally, it will address the major research design issues of currently available listening studies and provide suggestions for improvement in future research.

• Communications for Statistical Applications and Methods
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• v.18 no.3
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• pp.267-275
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• 2011

According to recent studies, Bayesian information criteria(BIC) is proposed to determine the structural dimension of the central subspace through sliced inverse regression(SIR) with high-dimensional predictors. The BIC may be useful in K-means clustering inverse regression(KIR) with high-dimensional predictors. However, the direct application of the BIC to KIR may be problematic, because the slicing scheme in SIR is not the same as that of KIR. In this paper, we present empirical penalty term studies of BIC in KIR to identify the most appropriate one. Numerical studies and real data analysis are presented.

• Journal of Information Technology Applications and Management
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• v.16 no.4
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• pp.223-244
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• 2009

Defense R&D is an essential investment for the national security. Recently our nation has also begun to initiate a number of defense R&D projects. As a lot of fund and resources are allocated to these projects, we need to identify which projects to initiate and then how to manage these projects well. Though there have been a number of studies on R&D projects in commercial sector, there are only a few studies in defense R&D sector. Moreover, these existing defense R&D studies mainly deal with the former issues, which are occurring at the stage of project planing. We are more concerned with project management issues, such as how to manage projects that had already been evaluated to undertake at the planning stage. Specifically our study aims to identify project management factors leading to the success of defense R&D projects. Results of the empirical analysis indicate that management support, user-driven requirements management, and project planning capability are key elements for project performance.