• Environmental and Resource Economics Review
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• v.12 no.4
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• pp.687-708
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• 2003

The purpose of this paper is to introduce time-series causality analysis by combining time-series technique with graph theory. Vector autoregressive (VAR) models can provide reasonable interpretation only when the contemporaneous variables stand in a well-defined causal order. We show that how graph theory can be applied to search for the causal structure In VAR analysis. Using Maryland crop cash prices and CBOT futures price data, we estimate a VAR model with directed acyclic graph analysis. This expands our understanding the degree of interconnectivity between the employed time-series variables.

• Journal of Convergence for Information Technology
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• v.9 no.6
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• pp.65-74
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• 2019

The purpose of this study is to reveal the causal relationship between core categories experienced by firefighters in the organization based on the grounded theory as a method of qualitative research. In this study, we interviewed 50 firefighter information providers who work in Seoul in 2014, 2017, and 2018, and conducted a research model that shows the causal relationship of core categories through open coding, axial coding, and selective coding. As a result, compassion experienced by information providers is revealed as a core category, and this compassion has a positive effect on positive work related identity, collective self esteem, and job performance. Therefore, the theoretical implication of this study is that it has derived a research model that shows the causal relationship between compassion and job performance based on grounded theory as a qualitative research methodology. This study will contribute to the formation of the organizational culture that enables firefighters who desperately need compassion in the fire department organization to more actively exchange compassionate actions.

• Health Policy and Management
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• v.5 no.2
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• pp.173-201
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• 1995

A causal model of organizational commitment on the basis of Western literature was tested with a sample of 1,164 employees from two university hospitals in Korea. The model contains three groups of determinants : environmental variables(job opportunity, spouse support, and parent support), psychological variables(met expectations, work involvement, positive affectivity, and negative affectivity), and structural variables(job autonomy, work unit control, routinization, supervisor support, coworker support, role ambiguity, role conflict, workload, resource inadequacy, distributive justice, promotional chances, job security, job hazarda, and pay). The data were colleted with questionnaires and analyzed with the LISREL maximum likelihood method. It is found that (1) the following variables, listed in order of size, have significant total effects on organizational commitment : job satisfaction, met expectations, supervisor support, job security, routinization, job opportunity, negative affectivity, work involvement, distributive justice, and promotional opportunity, (2) the model explains fifty-nine percent of the variance in organizational commitment, and (3) the link with expectancy theory is justified by the results for met expectations. Two conclusions can be drawn from these findings. First, the model of organizational commitment appears to be generalizable to Korean hospitals. Second, the model of organizational commitment should include such theoretical variables as environmental, psychological, and structural factors.

• Korean System Dynamics Review
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• v.15 no.4
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• pp.129-159
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• 2014

This Study discuss exploring normative-prescriptive factors after the themes on Organizational learning categorize two descriptive/explanatory-perspectives, prescriptive/normative dimension. The former would contain information processing model, theory of action, organizing in organization, while Senge's suggestion on Learning Organization may compose the latter. Each perspective is reconstructed and reinterpreted into the causal mapping relationship founded on system thinking and SD. Underlying on the former try to discovery validities of the latter. But this study only put forward the integral-dynamic model of organizational learning without empirical simulation.

• The Journal of Korean Academic Society of Nursing Education
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• v.10 no.1
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• pp.54-63
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• 2004

The purpose of this study is to identify the factors that influence stress experienced by nursing students and to provide a perceived causal structure model among these variables. The ultimate goal of this study is to develop efficient guidance to clinical nursing education in this population. This study intends to apply perceived causal structure: network analysis method which was developed by Kelly(1983), and has been applied in nursing research. This method is selected to show dynamic relationship of stressor using network method. Data was collected from convenient sample of 186 junior college nursing students who had the clinical practice experience during 10 weeks. Data collection and analysis was conducted in 2 steps from December, 9, 2002 to February, 8, 2003. Step 1.: Data was collected using literature review(10 articles) to identify the causes of stress. Nine causes of stress were extracted. Step 2.: As perceived casual structure network study, data was collected using questionnaires which included 9 extracted cause and stress. The questionnaire contained a 10 X 10 grid table with 10 causes and effects printed. In network analysis, 'Yes' was scored as 1, 'No' was scored as 0, and the mean(maximum 1, minimum 0) was calculated. Construction of the network under inductive eliminative analysis which stopped the construction of the network when the consensual agreement level dropped near 50% was proceeded by adding causes in order of the mean rating level. In this study, construction of the final network was stopped by consensual agreement level of 52% of the total subjects. The results are summarized as follows : Step 1: Investigation of the causes of stress ; The extracted causes of stress from quality data was identified 9 categories ; negative nurse, lack of clinical practice opportunity, ambiguous role, negative patient, lack of nursing knowledge and skill, difficult of personal relations, inefficient clinical practice guidance, gap of theory and practice, lack of support. Step 2 : Construction of the perceived causal structure model ; 1) The most central cause of stress is ambiguous role in the systems of causation. 2) The distal cause of stress is inefficient clinical practice guidance 3) The causes that have a number of outgoing link are negative nurse, ambiguous role. 4) The causes that have a number of incoming link are ambiguous role, gap of theory- practice, lack of clinical practice opportunity, lack of nursing knowledge- skill. 5) There is a mutual relationship between stress and difficult of personal relations, stress and ambiguous role, ambiguous role and negative nurse, ambiguous role and lack of clinical practice opportunity, ambiguous role and lack of nursing knowledge-skill, lack of nursing knowledge-skill and gap of theory- practice. In conclusion, the network suggests that the first centre cause is related on ambiguous role and the second on negative nurse, inefficient clinical practice guidance in the systems of causation

• International Journal of Highway Engineering
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• v.14 no.6
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• pp.121-129
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• 2012

PURPOSES : Traffic accidents at intersections have been increased annually so that it is required to examine the causations to reduce the accidents. However, the current existing accident models were developed mainly with non-linear regression models such as Poisson methods. These non-linear regression methods lack to reveal complicated causations for traffic accidents, though they are right choices to study randomness and non-linearity of accidents. Therefore, to reveal the complicated causations of traffic accidents, this study used structural equation methods(SEM). METHODS : SEM used in this study is a statistical technique for estimating causal relations using a combination of statistical data and qualitative causal assumptions. SEM allow exploratory modeling, meaning they are suited to theory development. The method is tested against the obtained measurement data to determine how well the model fits the data. Among the strengths of SEM is the ability to construct latent variables: variables which are not measured directly, but are estimated in the model from several measured variables. This allows the modeler to explicitly capture the unreliability of measurement in the model, which allows the structural relations between latent variables to be accurately estimated. RESULTS : The study results showed that causal factors could be grouped into 3. Factor 1 includes traffic variables, and Factor 2 contains turning traffic variables. Factor 3 consists of other road element variables such as speed limits or signal cycles. CONCLUSIONS : Non-linear regression models can be used to develop accident predictions models. However, they lack to estimate causal factors, because they select only few significant variables to raise the accuracy of the model performance. Compared to the regressions, SEM has merits to estimate causal factors affecting accidents, because it allows the structural relations between latent variables. Therefore, this study used SEM to estimate causal factors affecting accident at urban signalized intersections.

• Journal of the Korean Chemical Society
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• v.57 no.1
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• pp.147-158
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• 2013

This study is to search an optimal model on causal relationships of the motivations to learn and motivation strategy in chemistry education. The participants in this study are consisted of G and I high schools students (487) in Gwangju. They all answered to the questionnaire. Model I is hypothesized to be path model of the mediation between 'self-efficacy, achievement need, and entity theory of intelligence' and 'learning strategy and self-handicapping tendency of motivation strategy' by goal orientation to explore variables of study effecting the motivation strategy. And Model II is hypothesized path model of the mediation between goal orientation and 'learning strategy and self-handicapping tendency' by 'self-efficacy, achievement need, and entity theory' to explore variables of study effecting the motivation strategy. Based on these models, structural equation modeling techniques are used to evaluate for the path model among goal orientation(learning, performance approach, and performance approach goal orientation), self-efficacy, achievement need, entity theory of intelligence, self-handicapping tendency, and learning strategy in chemistry education. As the results, Model II is considered. Goodness-of-fit indexes of this model related modification models are identified and analyzed in phases. And this model is accomplished by correcting the model the fifth time to enhance goodness-of-fit indexes. In this optimal model II-5 (Fig. 3) on causal relationships of the motivations to learn and learning strategy (p

• Information Systems Review
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• v.25 no.3
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• pp.59-81
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• 2023

Elderly suicide problem has become worse in South Korea. With a rapid aging of the population, the trend of suicide among the elderly is expected to accelerate, preventing elderly suicide has been considered an important societal problem. Thus, we aim to investigate various factors that explain suicidal ideation and to develop a predictive model for suicidal ideation in the context of elderly people in South Korea. To this end, this study contributes to addressing the elderly suicide problem. By using seven-year panel data from the Korea Welfare Panel Survey, we extract various potential causal factors for elderly suicidal ideation based on interpersonal theory of suicide and social disorganization theory. Then a panel logit model was employed to assess the impacts of potential factors on suicidal ideation and deep learning and machine learning algorithms were used to develop a predictive model for suicidal ideation of elderly people. The results of our study provide practical implications for preventing elderly suicide by identifying causal factors of suicidal ideation and a high suicidal risk group of the elderly. This study sheds light on synergy of mixed methodology and provides various academic implications.

• The Journal of Information Technology and Database
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• v.3 no.2
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• pp.97-118
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• 1996

Information systems quality engineering is one of the most problematic areas in practice and research, and needs cooperative efforts between practice and theory [Glass, 1996]. A model for evaluating the quality of system development process and ensuing success is proposed based on information processing theory of project unit design. A nomological net among a set of quality variables is identified from prior research in the areas of organization science, software engineering, and management information systems. More specifically, system development success was modelled as a function of project complexity, system development modelling environment, user participation, project unit structure, resource availability, and the level of iterative nature of development methodology. Based on the model developed from the information processing theory of project unit design in organization science. appropriate quality metrics for each variable in the proposed model are matched. In this way, a framework of relevant systems development and success quality metrics for controlling systems development processes and ensuing success is proposed. The causal relationships among the constructs in the proposed model are proposed as future empirical research for academicians and as managerial tools for quality managers. The framework and propositions help quality manager to select more parsimonious quality metrics for controlling information systems development processes and project success in an integrated way. Also this model can be utilized for evaluating software quality assurance programmes, which are developed and marketed by many vendors.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2008.10a
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• pp.5-8
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• 2008

This study proposed the Knowledge Base Building method reflecting the user's preferences based on the fuzzy set theory to develop information contents which support pedestrian's navigation. This research evaluated subject's preferences on the commercial spaces set to the hypothetical destination. Also it surveyed the causal relationship between the visual characteristics and the emotional characteristics to propose the methods of Navigation Knowledge Base (NKB). The NKB was composed by three elements; 1.the correlation model between emotional characteristics, 2.the causal relationship between visual characteristics and emotional characteristics, 3.the transformation model between visual characteristics and the physical characteristics.