• Journal of Navigation and Port Research
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• v.40 no.3
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• pp.139-146
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• 2016

Due to the continuous increasement of the container cargoes, each container port market has been growing as well. Moreover, the competition among container terminal operators located in the same port is also growing in order to attract more container cargoes. This paper looked into the market structures, market conducts and market performances of container ports in Busan and Shanghai. The index which has been most widely used to measure market structure, the Hirschman-Herfindahl Index (HHI), is computed by squaring each supplier's market share, then adding the squared shares. This paper estimated the market performance as profitability (PCM, ROA), growth (total TEU, rate of the increasement of TEU) and examined the effects of the HHI on the profitability and growth in a container terminal operators in Korea and China. The major findings of this study is that the market structure has effects on market performance in Busan port (total TEU) and Shanghai port (PCM, ROA and total TEU). As a result of analysing this study, market structure has an effect on market performance in Busan and Shanghai port, but the power of influence can be changed by market concentration index and various market conduct of companies.

• Journal of Intelligence and Information Systems
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• v.26 no.1
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• pp.23-45
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• 2020

Big data is creating in a wide variety of fields such as medical care, manufacturing, logistics, sales site, SNS, and the dataset characteristics are also diverse. In order to secure the competitiveness of companies, it is necessary to improve decision-making capacity using a classification algorithm. However, most of them do not have sufficient knowledge on what kind of classification algorithm is appropriate for a specific problem area. In other words, determining which classification algorithm is appropriate depending on the characteristics of the dataset was has been a task that required expertise and effort. This is because the relationship between the characteristics of datasets (called meta-features) and the performance of classification algorithms has not been fully understood. Moreover, there has been little research on meta-features reflecting the characteristics of multi-class. Therefore, the purpose of this study is to empirically analyze whether meta-features of multi-class datasets have a significant effect on the performance of classification algorithms. In this study, meta-features of multi-class datasets were identified into two factors, (the data structure and the data complexity,) and seven representative meta-features were selected. Among those, we included the Herfindahl-Hirschman Index (HHI), originally a market concentration measurement index, in the meta-features to replace IR(Imbalanced Ratio). Also, we developed a new index called Reverse ReLU Silhouette Score into the meta-feature set. Among the UCI Machine Learning Repository data, six representative datasets (Balance Scale, PageBlocks, Car Evaluation, User Knowledge-Modeling, Wine Quality(red), Contraceptive Method Choice) were selected. The class of each dataset was classified by using the classification algorithms (KNN, Logistic Regression, Nave Bayes, Random Forest, and SVM) selected in the study. For each dataset, we applied 10-fold cross validation method. 10% to 100% oversampling method is applied for each fold and meta-features of the dataset is measured. The meta-features selected are HHI, Number of Classes, Number of Features, Entropy, Reverse ReLU Silhouette Score, Nonlinearity of Linear Classifier, Hub Score. F1-score was selected as the dependent variable. As a result, the results of this study showed that the six meta-features including Reverse ReLU Silhouette Score and HHI proposed in this study have a significant effect on the classification performance. (1) The meta-features HHI proposed in this study was significant in the classification performance. (2) The number of variables has a significant effect on the classification performance, unlike the number of classes, but it has a positive effect. (3) The number of classes has a negative effect on the performance of classification. (4) Entropy has a significant effect on the performance of classification. (5) The Reverse ReLU Silhouette Score also significantly affects the classification performance at a significant level of 0.01. (6) The nonlinearity of linear classifiers has a significant negative effect on classification performance. In addition, the results of the analysis by the classification algorithms were also consistent. In the regression analysis by classification algorithm, Naïve Bayes algorithm does not have a significant effect on the number of variables unlike other classification algorithms. This study has two theoretical contributions: (1) two new meta-features (HHI, Reverse ReLU Silhouette score) was proved to be significant. (2) The effects of data characteristics on the performance of classification were investigated using meta-features. The practical contribution points (1) can be utilized in the development of classification algorithm recommendation system according to the characteristics of datasets. (2) Many data scientists are often testing by adjusting the parameters of the algorithm to find the optimal algorithm for the situation because the characteristics of the data are different. In this process, excessive waste of resources occurs due to hardware, cost, time, and manpower. This study is expected to be useful for machine learning, data mining researchers, practitioners, and machine learning-based system developers. The composition of this study consists of introduction, related research, research model, experiment, conclusion and discussion.

• Journal of Korean Library and Information Science Society
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• v.55 no.2
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• pp.219-242
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• 2024

This study examined the output performance of papers published in international journals in the LIS field over the past 20 years and used the Gini coefficient and Hirschman-Herfindahl (HHI) index to understand the international gap in academic paper output and its changes. In addition, the characteristics of academic publications were visualized focusing on the top producing countries of academic papers, and differences according to sub-research areas were also identified. As a result of the analysis, first, although the United States and China are leading the publication of papers over the past five years, the results produced by the Netherlands showed relatively high influence and international and industrial cooperation results. Second, a high inter-country gap index (g= 0.7-0.8) has been maintained in terms of paper production and citation volume over the past 20 years, but the concentration of top countries is showing a trend of easing over time, as CR3 (Concentration Ration 3) decreased from 63.3% to 43.2%, HHI decreased from 2,129.6 to 976.1. Third, the LS field showed the highest gap between countries and a high degree of concentration centered on the United States, while the SM field was confirmed to be the most dispersed.

• Journal of Digital Convergence
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• v.18 no.6
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• pp.65-79
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• 2020

With the rapid development of China's economy, the aviation industry, as an important part of transportation services, has undoubtedly achieved rapid development. However, there is hardly any academic work that was based on the development of the top airlines in the Chinese airline industry. Hence, this study provides empirical research that takes into account the longitudinal development of the top 20 airlines in China from 2009 to 2018. The throughput volumes (cargo and passenger) of the airlines were analyzed by concentration indicators, namely the concentration ratio (CR), the Herfindahl- Hirschman index (HHI), the Gini coefficient, and the shift-share analysis (SSA). In this paper, the top 20 airlines have been analyzed in terms of the passenger and cargo throughput from 2009 to 2018. The calculation results of CR6, HHI and the Gini coefficient show that the airlines were extremely deconcentrated. In addition, by comparing the ABSGR of passenger and cargo throughput, it is shown that China's aviation industry is dominated by four airlines- Air China, China Eastern Airlines, China Southern Airlines and Hainan Airlines. In the future study, it is necessary to explore growth strategies to find niche markets for passenger and cargo transportation.

• Journal of Digital Convergence
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• v.13 no.10
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• pp.405-413
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• 2015

The purpose of this study is to measure the level of competition in the degree of Regional Public Hospital that can provide a basis for establishing an effective management strategy and analysis of the financial performance. Investigation period of the Regional Public Hospital HHI(Herfindahl-Hirschman Index) over three years from 2010, which was unknown until 2012, index and management performance evaluation criteria, a total of 31 were selected as Regional Public Hospital surveyed. In the conclusions, it showed that the most concentrated market with high financial performance, a significant correlation between the degree of local competition and financial indicators showed. The Regional Public Hospital for trends according to the degree of competitive local medical market and therefore is required to establish policies and practices to ensure competitiveness and public interest in the region. The Regional Public Hospital in order to preempt the lead for the competitiveness of other institutions will be considered in the strategy, such as improving medical services and capital investment.

• International Journal of Advanced Culture Technology
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• v.10 no.2
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• pp.1-11
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• 2022

Purpose: The purpose of this study was to empirically test a model of associations linking locations and competition among nursing homes (NHs), mediated by facility grade and registered nurse (RN) turnover, on activities of daily living (ADLs) in Korean NHs. Methods: This study used a cross-sectional design to identify causal factors on NH residents' ADLs. Data were collected from June 2017 to August 2017. A disproportionate stratified cluster sampling method of NHs across Korea was used to gain representation. The collected data consisted of location and the Herfindahl-Hirschman Index (HHI), RN turnover rate, facility grade, and NH residents' ADLs. Results: All pathways affecting ADLs were not significant, and the effect on facility grade was significant in RN turnover (β = -.59, p < .001). RN turnover associated negatively with facility grade. In other words, the higher the RN turnover, the worse the facility grade. Conclusion: This study is the first to examine the impact of location and HHIs, mediated by RN turnover rate and facility grade, on NH residents' ADLs. To improve residents' ADLs, subsequent studies are needed to identify the factors affecting ADLs utilizing other variables because this study did not identify factors that affect ADLs.

• Journal of Digital Convergence
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• v.16 no.4
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• pp.49-54
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• 2018

Russia has access to unique port locations and routes, one of them is North Sea route, which have been a major debate topic for last several decades. In order to handle any shipments along the route, an adequate and capable port system must be present. This study aims to identify development and competition patterns from 2007 to 2016 of Russian ports in the Arctic basin, concentration trends in particular. The objectives achieved through utilizing the Herfindahl-Hirschman Index (HHI), concentration ratio (CR), the Gini coefficient and Lorenz curve, and shift-share analysis. Results demonstrate concentration trend, positive overall growth and lack of real competition. Originality of this study lies in the fact that certain analysis had not been done in previous studies, but importance of it may be found in several papers. Findings of this paper may assist policy-makers, port authorities and other researchers in understanding and further study on the region.

• Journal of Korea Port Economic Association
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• v.37 no.1
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• pp.103-119
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• 2021

Ports in Korea have been increasing in terms of volume while they have performed functions and roles such as industrial ports in promoting industries of their hinterlands as well as commercial ports supporting imports and exports. Nevertheless, specialization degree is different from port to port by cargo type and the changes in cargo volume. This study aims to analyze the structural changes and the degree of concentration and specialization by cargo type and port between 2001 and 2020. Top 10 ports were analyzed in terms of traffic volume by categorizing liquid, dry, general cargo and containers. HHI(Herfindahl-Hirschman Index), LQ(Location Coefficient), and shift-share analysis were employed in order to identify the degree of concentration, specialization and changes in cargo volume by port and cargo type. As a result of the analysis, the degree of port concentration and specialization for each cargo of 4 categories have maintained a high level, and no significant difference were found in fluctuations over the past 20 years. As a result of calculating the flucation of cargo volume through the shift-share analysis, the growth rate of liquid cargo was high in Yeosu Gwangyang Port, Pyeongtaek Dangjin Port in dry cargo, and Busan Port in general cargo and container ports. The result implies that it is not expected that the structural changes including degree of cargo concentration, specialization and relative fluctuation of cargo volume is significant in Korean ports in the future since the effects of economies of scale and clustering were achieved to the great degree.

• Journal of Digital Convergence
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• v.18 no.6
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• pp.143-156
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• 2020

In Southern Vietnam, the competition among Inland Clearance Depot (ICD) has resulted in deconcentration tendencies and shifting share situations. However, related research on Southern Vietnam ICDs in particular and ICDs in Vietnam in general has been extremely limited. Hence, In this study, empirical research is conducted on ICDs located in southern Vietnam from 2010 to 2017. The throughput volume data of ICDs is analyzed by concentration indicators, namely the concentration ratio (CR), the Herfindahl-Hirschman Index (HHI), the Gini coefficient, the Lorenz curve, and the shift share analysis (SSA). The results of adopting all the methodologies indicate that deconcentration was the mainstream trend for ICDs in Southern Vietnam during the period of 2010-2017. The findings provide insights into the process of container terminal development and have academic and managerial implications. The strengthening of the competitiveness of Vietnamese container ports and ICDs could affect the competing Southeast Asian neighbors by facilitating the port of more shipping companies.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.7
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• pp.349-360
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• 2020

The study aims to empirically examine the determinants of bank margins from Pakistan, an emerging South Asian economy. To elucidate the importance of the Pakistani banking sector, secondary data has been used, which was extracted from the annual accounts of twenty-four Pakistani scheduled commercial banks (20 conventional, four full-fledged Islamic) over a sample period of 2006 to 2017. The factors identified in the dealership model and the subsequent empirical developments in the dealership model categorized as bank-specific, diversification, regulatory, and industry concentration are analyzed by applying the most-common linear dynamic panel-data estimator, the Generalized Method of Moments (GMM) estimator, developed by Arellano and Bond (1991). The findings reveal that, among the bank-specific variables, funding cost, credit risk, managerial efficiency, market share, and operating cost are significant predictors of bank margins. For diversification variables employed in the study, both variables including net non-interest income and asset diversity are as well significant predictors of bank margins. It is also found that the market concentration variable proxied by the Herfindahl-Hirschman Index (HHI) is significantly predicting bank margins. Subsequently, one of the regulatory variables, the opportunity cost of holding reserves, and one bank-specific variable, the degree of risk aversion, are insignificant in the model.