• The Journal of Information Systems
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• v.29 no.1
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• pp.289-301
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• 2020

Purpose This study analyzes whether Internet search of cryptocurrency has a causal relationship to return and volatility of cryptocurrency. Design/methodology/approach Google Trend was used as a measure of the level of Internet search, and the parametric tests of Granger causality in the 1st moment and the 2nd moment were adopted as the analysis method. We used Bitcoin's dollar-based price, which is the No. 1 market value among cryptocurrency. Findings The results showed that the Internet search measured by Google Trends has a causal relationship to cryptocurrency in both average and volatility, while there is a difference in causality and its degree according to the search area and category that Google Trend user should set. Because the Granger causality is based on the improvement of prediction, the analysis results of this study indicate that Internet search can be used as a leading indicator in predicting return and volatility of cryptocurrency.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.607-617
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• 2020

This study investigates the causal relationship between public and private external debt and economic growth in developing countries. Our model includes 18 selected Asian developing and transition economies from 1995 thru 2019. We employ the dynamic heterogeneous panel data methods, pooled mean group (PMG), robust cross-sectional augmented autoregressive distributed lag (CS-ARDL), and pairwise panel causality test. The results of PMG and CS-ARDL show the existence of causality between external debt and economic growth both in the short-run and long-run. The pairwise Granger causality test found the bidirectional causal relationship runs from total external debt, public external debt, and private external debt to economic growth and economic growth to external debt. The results showed first the existence of causality in the short-run and long-run between external debt and economic growth and the second, bi-directional causality that runs from external debt to economic growth and economic growth to external debt. Both the dynamic models and robust estimator found the same inferences about the impact of main variables on economic growth in Asian developing and transition economies. The findings of this study suggest to assure debt management, investment in productive sectors, increase domestic savings, decrease external dependency, and focus on international trade.

• Spatial Information Research
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• v.16 no.2
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• pp.219-236
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• 2008

Data stream collected from sensors contain a large amount of useful information including causality relationships. The causality join query for data stream is to retrieve a set of pairs (cause, effect) from streams of data. A part of causality pairs may however be lost from the query result, due to the delay from sensors to a data stream management system, and the limited size of sliding windows. In this paper, we first investigate spatial, temporal, and spatio-temporal aspects of the causality join query for data stream. Second, we propose several strategies for sliding window management based on these observations. The accuracy of the proposed strategies is studied by intensive experiments, and the result shows that we improve the accuracy of causality join query in data stream from simple FIFO strategy.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.3
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• pp.139-154
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• 2021

This study's impetus is to explore fresh evidence to answer the question, i.e., whether remittances asymmetrically influence financial development in Bangladesh from 1975 to 2019. The study employs several tests, i.e., nonlinear unit root test, Autoregressive Distributed Lagged (ARDL), NARDL, and asymmetric causality test for establishing the pattern of association. Nonlinear unit root tests confirm that variables follow a nonlinear system of being stationary after the first difference. nonlinearity among variables is investigated by performing the BDS test and nonlinear OLS. Directional causality is investigated through both linear and nonlinear effects of remittance inflows by following the non-granger casualty test. The test statistics of Fpass and tBDM showed the Long-run cointegration in the empirical model and positive effect running from remittances inflow to financial development both in the long-run and short-run. Furthermore, the results of a standard Wald test divulge the presence of long-run and short-run asymmetry. Asymmetry causality test established unidirectional causality due to positive and negative shocks in remittances inflows to Bank-based financial development and feedback hypothesis hold for explaining causality between positive and negative shocks in remittance inflows and Stock-based financial development.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.8
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• pp.149-156
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• 2021

Gambling negatively affects the economy, and it brings unwanted financial, social, and health outcomes to gamblers. On the one hand, unemployment is argued to be a leading cause of gambling. On the other hand, gambling can cause unemployment in the second-order via gambling-induced poor health, falling productivity, and crime. In terms of significant effects, previous studies were able to establish an association, but not causality. The current study examines the time-sequence and contemporaneous causalities between lottery gambling and unemployment in Thailand. The Granger causality and directed acyclic graph (DAG) tests employ time-series data on gambling- and unemployment-related Google Trends indexes from January 2004 to April 2021 (208 monthly observations). These tests are based on the estimates from a vector autoregressive (VAR) model. Granger causality is a way to investigate causality between two variables in a time series. However, this approach cannot detect the contemporaneous causality among variables that occurred within the same period. The contemporaneous causal structure of gambling and unemployment was identified via the data-determined DAG approach. The use of time-series Google Trends indexes in gambling studies is new. Based on this data set, unemployment is found to contemporaneously cause gambling, whereas gambling Granger causes unemployment. The causalities are circular and last for four months.

• Korea Trade Review
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• v.45 no.4
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• pp.107-123
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• 2020

The purpose of this paper is to analyze the Granger Causality relations between Korean FDI and exports in Vietnam using time-series from 2005 to 2019. Using 15-industry semi-annual data of Korean FDI and exports toward Vietnam, the Granger Causality Tests were conducted. Var and VEC models were decided after unit-root and cointegration tests of variables. Findings and implications of the empirical tests are as follows. First, unexpectedly FDI did not Grange-cause exports only in one direction. In two industries, food & beverage and medical & chemical products, there were Granger causality relations in both directions. In eight industries including print, publishig, pulp & paper, exports did Grange-cause FDI. In the rest of five industries including automative & trailer industry, there were no Granger Causality relation in both directions. Second, we presume that the both direction-causality relations are desirable phenomenon for Korea. Because Korean FDI and exports are increasing at the same time. On the other hand, substitution relationship between Korea's exports and FDI occur in the industry that exports did Grange-cause FDI. Finally, more in-depth researches considering Vietnam's consumer demand and the oriented characteristics of FDI are needed. The results of this research will contribute to understand structural patterns of FDI and exports in Vietnam and to make investment and export decisions.

• Environmental and Resource Economics Review
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• v.26 no.1
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• pp.37-56
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• 2017

This study analyzed the mutual causal relationship between energy consumption, production, and export for manufacturing industry in Korea. The Korean manufacturing industry was divided into nine industries and panel data was constructed from 1991 to 2013. The panel Granger causality test method developed by Demitrescu and Hurlin (2012) was used along with the Vector Error Correction Model. This analysis showed that there was Granger Causality from production to energy consumption, from exports to energy consumption. However, Granger Causality was not established in the opposite direction. Therefore, this result supports the conservation hypothesis of Qzturk (2010) that energy-saving policies in the manufacturing sector can be implemented without adverse effects on production or exports in short-run. There is a long-run cointegrating relationship between production, energy consumption, exports, labor, and capital in the Korean manufacturing sector. Furthermore, the energy consumption contributes to the increasing of production in long-run equilibrium relationship.

• The Korean Society of Law and Medicine
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• v.17 no.2
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• pp.57-81
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• 2016

It can determine the outcome of the lawsuit whether or not there is a causality between the medical malpractice of a physician and the patient's injury when the patient is filing a lawsuit against the physician in order to pursue civil liability for a medical accident. In medical malpractice lawsuits, it is not easy to judge causality between different civil cases because of the special nature of medical care. Also, information such as medical records is concentrated on doctors and the medical knowledge of the patient is relatively insufficient compared with the doctor. Therefore, it is recognized through medical malpractice lawsuits that the burden of proof of the causality burdened by the plaintiff patient is relaxed. In this paper, I examine the legal theory on how to recognize causality in medical civil liability and then concern the attitude of the case in Korea, which is divided into the types of the causality - such as the case of general medical practice, explanation duty, no causality with medical malpractice.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.1
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• pp.136-151
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• 2016

Flexible large-scale WLANs are now widely deployed in crowded and highly mobile places such as campus, airport, shopping mall and company etc. But network management is hard for large-scale WLANs due to highly uneven interference and throughput among links. So the traffic is difficult to predict accurately. In the paper, through analysis of traffic in two real large-scale WLANs, Granger Causality is found in both scenarios. In combination with information entropy, it shows that the traffic prediction of target AP considering Granger Causality can be more predictable than that utilizing target AP alone, or that of considering irrelevant APs. So We develops new method -Granger Causality and Vector Auto-Regression (GCVAR), which takes APs series sharing Granger Causality based on Vector Auto-regression (VAR) into account, to predict the traffic flow in two real scenarios, thus redundant and noise introduced by multivariate time series could be removed. Experiments show that GCVAR is much more effective compared to that of traditional univariate time series (e.g. ARIMA, WARIMA). In particular, GCVAR consumes two orders of magnitude less than that caused by ARIMA/WARIMA.

• Safety and Health at Work
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• v.3 no.2
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• pp.110-116
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• 2012

Establishing a causal relationship between factors at work and disease is difficult for occupational physicians and researchers. This paper seeks to provide arguments for the judgement of evidence of causality in observational studies that relate work factors to disease. I derived criteria for the judgement of evidence of causality from the following sources: the criteria list of Hill, the approach by Rothman, the methods used by International Agency for Research on Cancer (IARC), and methods used by epidemiologists. The criteria are applied to two cases of putative occupational diseases; breast cancer caused by shift work and aerotoxic syndrome. Only three of the Hill criteria can be applied to an actual study. Rothman stresses the importance of confounding and alternative explanations than the putative cause. IARC closely follows Hill, but they also incorporate other than epidemiological evidence. Applied to shift work and breast cancer, these results have found moderate evidence for a causal relationship, but applied to the aerotoxic syndrome, there is an absence of evidence of causality. There are no ready to use algorithms for judgement of evidence of causality. Criteria from different sources lead to similar results and can make a conclusion of causality more or less likely.