• Environmental and Resource Economics Review
• /
• v.19 no.1
• /
• pp.3-21
• /
• 2010

By the significant structural change in 1999, a partial privatization has occurred in Korean fossil-fuel power generation sector. Under the current price scheme wholesale electricity price is dependent on output size, and hence, may not satisfy the assumption of price-taking producers. The purpose of our study is constructing the productivity change measurements of Korean power generation sector taking into account possibly imperfect competition and variable returns to scale. Our approach based on Harrison (1994) and Levinsohn (1993) derives the plant-level productivity measurements of the period between 2001 and 2007, as well as the measurements of mark-ups and returns to scale. It is shown that the mark-up size is dependent on the plants' fuel type and is decreasing over time. Allowing for imperfect competition and variable returns to scale adjusts the productivity measurements substantially.

• Industrial Engineering and Management Systems
• /
• v.9 no.2
• /
• pp.97-106
• /
• 2010

Can eBay.com's fee structure coordinate the channel? It's a critical strategic problem in e-commerce operations and an interesting research hypothesis as well. eBay's fees include three parts: monthly subscription fee, insertion fee, and final value fee (i.e., a revenue sharing portion), which represent a generic form of revenue sharing fee structure between the retailer and the vendor in a supply chain. This research deals with such a channel consisting of a price-setting vendor who sells products through eBay's marketplace exclusively to the end customers. The up- and down-stream channel relationship is consignment-based revenue sharing. We use a game-theoretic approach with assumption of the retailer (i.e., eBay.com) being a Stackelberg-leader and the vendor being a follower. The Stackelberg-leader decides on the terms of revenue sharing contract (i.e., fee structure), and the follower (vendor) decides on how many units to sell and the items' selling price. This study formulates several profit-maximization models by considering the effects of the retail price on the demand function. Under such settings, we show that eBay's fee structure can improve the channel efficiency; yet it cannot coordinate the channel optimally.

• Journal of Service Research and Studies
• /
• v.6 no.1
• /
• pp.83-95
• /
• 2016

We examine the information transmission between the Service Industrial Production Index and the Service Industrial Wholesale and Retail Index, based on the returns data offered by the Korea Bank. The data includes daily return data from January 2000 to September 2015. Utilizing a dynamic analytical tool-the VAR model, Granger Causality test, Impulse Response Function and Variance Decomposition have been implemented. The results of the analysis are as follows. Firstly, results of Granger Causality test suggests the existence of mutual causality the Service Industrial Production Index precede and have explanatory power the Service Industrial Wholesale and Retail Index However the results also identified a greater causality and explanatory power of the Service Industrial Wholesale and Retail Index over the Service Industrial Production Index. Secondly, the results of impulse response function suggest that the Service Industrial Production Index show immediate response to the Service Industrial Wholesale and Retail Index and are influenced by till time 5 From time 2, the impact gradually disappears. Also the Service Industrial Wholesale and Retail Index show immediate response to the Service Industrial Production Index and are influenced by till time 2.5, the impact gradually disappears. Lastly, the variance decomposition analysis shows that the changes of return of Service Industrial Production Index are dependent on those of the Service Industrial Wholesale and Retail Index. This implies that returns on the Service Industrial Production Index have a significant influence over returns on the Service Industrial Wholesale and Retail Index. It contributes to the understanding of market price formation function through analysis of detached the Service Industrial Production Index and Service Industrial Wholesale and Retail Index. Finally, our results can be used as a guide by the Korea Bank and Republic of Korea and as well as Statistics Korea.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.59 no.4
• /
• pp.700-706
• /
• 2010

Carbon costs, either in the form of a carbon tax or through permit prices in an emissions trading scheme, would ultimately be reflected in higher electricity prices. This price "pass-through" is very critical to the effective design of new policies to curb the amount of carbon emissions. This paper sets out in a structured way the factors that determine price pass-through and how carbon costs would impact on the electricity market and the existing coal-fired power plants. It is shown that pass-through can vary drastically if the underlying dispatch potential of generators varies significantly across alternative emissions reduction scenarios. It can also vary depending on the availability of competing cleaner forms of generation. Pass-through as a measure of business performance is therefore hard to generalize across different circumstances and should be interpreted carefully.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.42 no.1
• /
• pp.1-17
• /
• 2017

This study investigates a buyer-supplier supply chain, in which a buyer delegates the production process to a supplier as in many practices. The consumer's buying intention and overall supply chain performance are affected not only by the buyer's decision on sales price but also by the supplier's decision on product quality. Therefore, the buyer has a motivation to control the supplier's quality investment. Among various incentive schemes that the buyer can adopt in practice, we consider a revenue-sharing contract and investigate its unique characteristics. By comparison with a typical wholesale price contract, we reveal that the revenue-sharing contract can enhance supply chain's overall performance, including quality, demand, and profits of not only overall supply chain but also each player. We contribute to the academia and the supply chain practice by providing important guidelines in adopting incentive schemes and effectively managing product quality in a supply chain.

• Korean System Dynamics Review
• /
• v.6 no.2
• /
• pp.25-35
• /
• 2005

This paper describes the mechanism for new investment to appear in waves of boom and bust causing alternative periods of over and under supply of electricity in Korean market. A system dynamics model was developed to describe the dynamic behavior of new investment in Korean market. The simulation results show the boom and bust cycle in the new investments. When the market price is high, investors decide to build new power plants. However, it takes some delay time to complete new power plants. When the new power plants are being added into the grid, the supply increases and the wholesale price begins to decrease. This causes the cancellation of new power plant or delay the construction. This mechanism causes the boom and bust cycle in new investment.

• Proceedings of the Korea Inteligent Information System Society Conference
• /
• 2003.05a
• /
• pp.255-263
• /
• 2003

A multi-agent system designed to represent newly deregulated electricity markets in the USA is aimed at testing the capability of the multi-agent model to replicate the observed price behavior in the wholesale market and developing a smart business intelligence which quickly searches the optimum offer strategy responding to the change in market environments. Simulation results show that the optimum offer strategy is to withhold expensive generating units and submit relatively low offers when demand is low, regardless of firm size; the optimum offer strategy during a period of high demand is either to withhold capacity or speculate for a large firm, while it is to be a price taker a small firm: all in all, the offer pattern observed in the market is close to the optimum strategy. From the firm's perspective, the demand-side participation as well as the intense competition dramatically reduces the chance of high excess profit.

• Journal of Practical Agriculture & Fisheries Research
• /
• v.14 no.1
• /
• pp.23-45
• /
• 2012

The objective of this study is to provide development strategies in the production and distribution system of highland Chinese cabbage by evaluating and analyzing problems of the current system, focusing on several main stages between production and distribution system of highland Chinese cabbage. Through interview of groups such as farmers, distributers in the main producing areas, commission merchants of the wholesale market and large-scale distributors the relavant information was collected. Also, data such as production situations in main producing areas, distribution conditions in the wholesale market was analyzed. The functions of highland Chinese cabbage were classified and the current state of highland Chinese cabbage distribution system was investigated to provide an overall insight into the highland Chinese cabbage distribution system. Also the factors which will affect a price of wholesale market and consumer of highland Chinese cabbage were examined. Finally problems and improvements in the production and distribution system through analysis of the distribution system of highland Chinese cabbage were provided. the main contents of this study are as follows. The first is to keep stability of production in main producing areas by applying a differentiated production method, for example, rainshelter cultivation method. The second is to establish the distribution system which the relevant information is opened transparently. The third is that the consistent cold transportation system from main producing areas to consumers must be built.

• Journal of Intelligence and Information Systems
• /
• v.21 no.1
• /
• pp.161-177
• /
• 2015

With the rapid evolution of technology, the size, number, and the type of databases has increased concomitantly, so data mining approaches face many challenging applications from databases. One such application is discovery of fraud patterns from agricultural product wholesale transaction instances. The agricultural product wholesale market in Korea is huge, and vast numbers of transactions have been made every day. The demand for agricultural products continues to grow, and the use of electronic auction systems raises the efficiency of operations of wholesale market. Certainly, the number of unusual transactions is also assumed to be increased in proportion to the trading amount, where an unusual transaction is often the first sign of fraud. However, it is very difficult to identify and detect these transactions and the corresponding fraud occurred in agricultural product wholesale market because the types of fraud are more intelligent than ever before. The fraud can be detected by verifying the overall transaction records manually, but it requires significant amount of human resources, and ultimately is not a practical approach. Frauds also can be revealed by victim's report or complaint. But there are usually no victims in the agricultural product wholesale frauds because they are committed by collusion of an auction company and an intermediary wholesaler. Nevertheless, it is required to monitor transaction records continuously and to make an effort to prevent any fraud, because the fraud not only disturbs the fair trade order of the market but also reduces the credibility of the market rapidly. Applying data mining to such an environment is very useful since it can discover unknown fraud patterns or features from a large volume of transaction data properly. The objective of this research is to empirically investigate the factors necessary to detect fraud transactions in an agricultural product wholesale market by developing a data mining based fraud detection model. One of major frauds is the phantom transaction, which is a colluding transaction by the seller(auction company or forwarder) and buyer(intermediary wholesaler) to commit the fraud transaction. They pretend to fulfill the transaction by recording false data in the online transaction processing system without actually selling products, and the seller receives money from the buyer. This leads to the overstatement of sales performance and illegal money transfers, which reduces the credibility of market. This paper reviews the environment of wholesale market such as types of transactions, roles of participants of the market, and various types and characteristics of frauds, and introduces the whole process of developing the phantom transaction detection model. The process consists of the following 4 modules: (1) Data cleaning and standardization (2) Statistical data analysis such as distribution and correlation analysis, (3) Construction of classification model using decision-tree induction approach, (4) Verification of the model in terms of hit ratio. We collected real data from 6 associations of agricultural producers in metropolitan markets. Final model with a decision-tree induction approach revealed that monthly average trading price of item offered by forwarders is a key variable in detecting the phantom transaction. The verification procedure also confirmed the suitability of the results. However, even though the performance of the results of this research is satisfactory, sensitive issues are still remained for improving classification accuracy and conciseness of rules. One such issue is the robustness of data mining model. Data mining is very much data-oriented, so data mining models tend to be very sensitive to changes of data or situations. Thus, it is evident that this non-robustness of data mining model requires continuous remodeling as data or situation changes. We hope that this paper suggest valuable guideline to organizations and companies that consider introducing or constructing a fraud detection model in the future.

• Korean Journal of Organic Agriculture
• /
• v.18 no.4
• /
• pp.489-509
• /
• 2010

The object of this study is to analyze marketing situations and to suggest developing issues for organic farming. Organic agricultural products (OAP) has been steadily grown by an annual 36.4 percent over the past ten years, and production of OAP took up 4.5 percent of the Environmentally friendly agricultural products (EFAP) in 2009. 9,403 farmers, cultivated area 13,343ha and production 108,810 M/T in Organic agriculture are respectively formed 0.8 percent, 0.8 percent and 0.6 percent of Korea agriculture in 2009. And production of livestock products to have been certificated from the year 2005 was over 10,000M/T in 2008. OAP is mainly distributed by direct marketing system. The market size of OAP is 188.5 billion in 2008 and has been grown by an annual 30.1 percent. The price difference between OAP and general agricultural products is about 65.8 percent. Several issues on the marketing system of OAP are as follows : overcost of OAP marketing socially, imbalance of supply and demand, absence of standard price, institutional insufficiency to marketing within wholesale market, retail price inflexibility of consumer's cooperative, and so on.