Traditional Markets Performance Analysis Considering the Impact of Large Discount Stores

Yoo,Byong-Kook,Kim,Soon-Hong 한국유통과학회 2019 KODISA ICBE (International Conference on Business Vol.2019 No.-

The support policy for the traditional market has been a uniform support method focused on facility investment. As a result, it did not show any remarkable achievement compared to huge financial support. Therefore, the need for differentiated support methods based on more rigorous performance evaluation for each traditional market has been raised. In this paper, we will modify the traditional DEA model using the two stage method for a more reasonable evaluation of the traditional markets. After calculating the bias-corrected estimator of efficiency scores using bootstrap from original ones in the first stage, the relationship between environment factors and the bias-corrected scores is assessed. Among the five environmental factors, the residential population and the presence of large discount stores or SSMs were statistically significant.

한국산 재료를 이용한 밀폐의 차음효과

백남원,유병국,이광묵 가톨릭대학산업의학센타 산업의학연구소 1977 韓國의 産業醫學 Vol.16 No.4

In industrial areas where noise level and the worker exposure time exceed the criteria, and evaluation should be made to determine the most economical solution to the problem. A large reduction in noise can be achieved by complete enclosure of a noise source. This study was carried out to determine the effect of Korean-made materials in noise reduction. A blower producing noise level of 91 dBA was used as a noise source, and plywood having surface density of 9.5 kg/㎥ and thickness of 1.8cm was used as sound-isolating partition and glass fivers of various densities and thicknesses were used as sound absorbing materials. Noise reduction effect of total and partial enclosures was evaluated. The results are summarized as follows. 1. When the blower was enclosed with and unlined enclosure constructed by plywood, the noise reductions by total and partial enclosures were 17㏈ and 9㏈ respectively at A-weighted measurements, which indicated lower effectiveness than the theoretical effect of the plywood. This could be resulted from the reverberant buildup in the enclosure. 2. To reduce the reverberation, glass fibers of various densites and thicknesses were covered inside the wall of enclosure and the effectiveness was as follow. 1) Noise reductions by plywood plus glass fibers having densities of 25-48 kg/㎥ and density of 100kg/㎥ were 20-25㏈ and 30㏈ respectively. 2) Noise reductions at 4,000 Hz by plywood plus 48kg/㎥ glass fibers having thicknesses of 2.5cm and 5.0cm were 31 and 41㏈ respectively. By doubling the thickness of glass fibers the noise reduction increased by 5㏈ at A-weighting. 3) The difference in noise reduction between total and partial enclosure was ranged from 5㏈ to 11㏈ at A-weighting. The higher the density of glass fibers were, the difference increased.

Regional Difference in Retail Product Association of Market Basket Analysis in US

Byong-Kook YOO(Byong-Kook YOO),Soon-Hong KIM(Soon-Hong KIM) 한국유통과학회 2023 유통과학연구 Vol.21 No.4

Purpose: Market basket analysis is one of the most frequently used methods in the retail industry today as a technique to discover the product association. It is empirically analyzed how these product associations differ regionally in the case of the United States. Research design, data, and methodology: Based on the purchasing data of consumer panels collected from 49 US states, the association rules for each state was extracted with the corresponding lift values indicating product association. The difference in lift values in 49 states by the association rule was compared and tested for 49 states and for 4 census regions (Northeast, Midwest, South, West). Results: The association rules of 3/4 of the same association rules show positive associations or negative associations depending on the lift values of the states. There were significant differences in the lift values for 49 states, and for 4 census regions. These significant differences in the lift values were found to be related to the distance between states and whether states belong to the same census region. Conclusions: Retail product associations shown by market basket analysis may vary depending on regional distance or regional heterogeneity. It is necessary to pay attention to these points in multi-store environment.

A Study on Employment-centric Industries in Incheon Using Machine Learning Method

Byong Kook Yoo,Soon Hong Kim 한국유통과학회 2017 한국유통과학회 학술대회 논문집 Vol.2017 No.-

The industrial structure in Incheon has a very significant difference compared with the change in the industrial structure of the whole country. Thus, reflecting those differences, the unemployment rate in Incheon has always been higher than the national average. The purpose of this study is to identify the employment - oriented industries in Incheon area using machine learning techniques. First, the relationship between employment ratio and employment by industry was examined through regression analysis. Second, we examined the characteristics of industrial areas with high employment rate through decision tree analysis. Third, a random forest model was used to predict regional employment changes. Through such a machine learning model, the Incheon area still has a base of traditional manufacturing, but it is characterized by the expansion of the service industry such as wholesale and retail business. Machine learning methods have multiple tools analyzing and reporting complicated non-linear relationship in data effectively. In addition, a random forest model was used to predict employment changes due to industrial structure changes. This machine learning model shows that beverage manufacturing industry has the highest employment rate in Incheon and expansion of service industry such as wholesale and retail business is prominent.

A Study on Competition Analysis in Retail Distribution Industry Using GIS in Seoul

YOO, Byong-Kook,KIM, Soon-Hong Korea Distribution Science Association 2021 유통과학연구 Vol.19 No.3

Purpose: This study aims to utilize geographic data to analyze how various retail formats of large-scale stores around the traditional market affect the performance of the traditional market in Seoul, Korea. Research design, data, and methodology: The two types of catchment areas were demarcated (circle of 1km radius and Thiessen polygon) for each traditional market, and the large-scale stores located within each catchment area were identified for 153 traditional markets in Seoul, Korea. Additionally, multiple regression analysis was utilized. Results: The results revealed that the influence on the performance of the traditional markets were different depending on the retail format of the large-scale stores. Large discount stores were found to have a negative effect on the sales and the visitors of traditional markets, whereas complex shopping malls and department stores had a positive effect on the traditional markets. Conclusions: As a result of the differences in the retail format such as product categories and leisure functions, the impact of some large-scale stores on the traditional market may have a greater agglomeration effect than the consumer churn effect. Therefore, it is suggested that in the regulation of these large-scale stores, the differences in retail format should be considered for the future.

A Study on Predicting Shopper’s Retail Format Choice

Byong Kook Yoo,Soon Hong Kim 한국유통과학회 2017 KODISA ICBE (International Conference on Business Vol.2017 No.-

As competition is getting fiercer between retail formats, the strategy to prevent shoppers from churning is very important in terms of shopper relationship management. In particular, as the traditional market is threatened and the national chain enters the market, the impact from entry of a national chain such as failure of shopper retention becomes an important concern not only for local retailers but also for local communities. Also, it is important for national chains to predict potential new shoppers in newly launched market because it is directly related to market entry feasibility. In this case, accurate predictions can become more important than the relationship analysis between the influential factors. In general, shopper churn for retail stores is known as partial churn, not complete churn. Therefore, it is necessary to develop a predictive model to consider not only retail format choice (i.e., national chains or traditional market) but also the possibility of cross-shopping derived from the partial churn. The existing (linear or logistic) regression model is a very useful tool for analyzing the relationship between influential factors, but it requires a preliminary assumption of the population and has limitations in establishing a predictive model of complex nonlinear relationships.

Formation of Employment Subcenters and Regional Industry Restructuring: Focusing Wholesale and Retail Sector in Incheon

Byong-Kook Yoo,Soon-Hong Kim 한국유통과학회 2020 유통과학연구 Vol.18 No.2

Purpose: This study examines the relationship between formation of employment subcenters and regional industrial structures in Incheon. Research design, data, and methodology: We used the five-year panel data from 2012 to 2016 in 146 basic municipal units of Incheon to analyze panel regression models. Gross employment density and employment to population ratio were used as indicators of employment subcenters formation. The entropy index and Hachman index were used for analyzing the diversity and heterogeneity of industrial structures. Result: The analyses of two panel regression models showed that for the formation of employment subcenters, both the Entropy and Hachman index were significantly negative in most models. But tertiary industry was shown to have a significant positive relationship in all models. In the wholesale and retail sector, it was found that the average number of employees in the employment subcenters is significantly higher than that in the non-employment subcenters. Conclusions: The specialization of the industrial structure rather than the diversification contributes to the formation of the employment subcenters in Incheon. In particular, it can be considered that the wholesale and retail sector plays a very important role in forming the employment subcenters in many areas of Incheon.

선택실험법 자료에서의 선호이질성 분석을 위한 혼합로짓모형 및 잠재계층모형의 활용

유병국 ( Byong Kook Yoo ) 한국환경경제학회·한국자원경제학회(구 한국환경경제학회) 2012 자원·환경경제연구 Vol.21 No.4

조건부 로짓(Conditional Logit: CL)모형은 모형추정 및 결과해석이 비교적 용이하다는 장점으로 널리 사용되는 반면에 응답자의 선호이질성(preference heterogeneity)을 충분히 반영하지 못한다는 한계를 가지고 있다. 본 연구에서는 최근 지배적인 방식으로 제시되고 있는 두개의 모형인 혼합로짓(Mixed Logit; ML)모형과 잠재계층모형(Latent Class Model; LCM)을 사용하여 우리나라 보령댐 주변 습지보호에 있어서 응답자간 선호이질성을 설명하고자 하였다. 6대광역시와 보령시 표본에 대하여 응답자별 이질성의 존재여부를 검토한 결과 두 지역간 뚜렷한 차이가 있음을 알 수 있었다. 즉 보령시의 경우에는 응답자간 선호이질성이 뚜렷하게 나타난데 반하여 6대광역시의 경우 응답자간 선호이질성이 거의 나타나지 않았다. 따라서 6대광역시의 경우에는 모수추정을 위해 CL 모형의 사용이 가능하나 보령시의 경우에는 선호이질성을 반영하기 위해 ML모형이나 LCM에 근거한 모수추정이 요구된다. 선호이질성의 원인을 규명하기 위하여 교차항이 있는 혼합로짓모형과 잠재계층모형을 고려할 수 있다. 교차항이 있는 혼합로짓모형의 경우 관찰되지 않은 개인단위의 이질성을 설명할 수 있는 장점이 있다. 그러나 두모형을 비교한 결과 LCM이 교차항이 있는 ML모형이 제공하지 않는 추가적인 정보를 보여주는 것으로 나타나고 있다. 따라서 본 연구에서의 응답자간 선호이질성은 혼합로짓모형에 의한 개인적인 수준보다 잠재계층모형에 의한 계층단위에서 더 잘 설명될 수 있다고 할 수 있다. Conditional Logit (CL) model is widely used since its model estimation and interpretation of results of the model is relatively easy, on the other hand, it has the limit of preference heterogeneity of respondents being not fully considered. In this study we used the two models, Mixed Logit (ML) Model and Latent Class Model (LCM) to explain preference heterogeneity of respondents for protection for Boryeong Dam wetland. As a result of the examination for heterogeneity in Boryeong city and six metropolitan areas, we found there was significant difference between two regions. While there was explicit preference heterogeneity within respondents in Boryeong city, we found little heterogeneity within respondents in six metropolitan areas. Thus in the case of six metropolitan areas, CL model can be used for parameter estimation while in the case of Boryeong city, WTP estimates are based on parameter estimates from ML model to reflect the heterogeneity within respondents. Additionally, ML model with interaction and 2-class LCM for respondents in Boryeong city were used to explain the sources of the heterogeneity. The ML model with interaction has advantage of explaining individual unobserved heterogeneity. However The comarison between these two models reflects the fact that LCM provided added information that was not conveyed in the ML model with interaction. Thus, Preference heterogeneity within respondents in this study may be better explained by class level through LCM rather than indiviual level through ML model.

소셜네트워크 분석을 통한 마케팅 전략

유병국(Byong-Kook Yoo),김순홍(Soon-Hong Kim) 한국콘텐츠학회 2013 한국콘텐츠학회논문지 Vol.13 No.5

입소문효과의 극대화를 위한 유력자의 역할은 트위터 네트워크에서도 매우 중요하다고 볼 수 있다. 본 논문에서는 기업 마케팅의 관점에서 트위터 유력자를 파악하고자 하였다. 기업의 마케팅 메시지가 가능한한 많은 사람들에게 노출되기 위해서는 특정인의 팔로어 수뿐만 아니라 계속적인 리트윗을 통해 입소문이 많이 확산되어야 할 것이다. 즉, 팔로어 수는 많은데 리트윗되지 않거나 리트윗은 많이 되는데 소수자에게주로 리트윗된다면 전체적인 노출의 정도는 미약하게 될 것이다. 트위터의 특정 검색네트워크 데이터를 이용한 그래프 비교를 통해 다음과 같은 사실을 확인할 수 있었다. 첫째, 리트윗이 없는 팔로어 유력자에 비하여 팔로어 유력자의 리트윗을 받는 상대적인 소수자들의 노출도가 크다는 것을 알 수 있었다. 둘째, 리트윗 유력자중에서도 팔로어 유력자에 의하여 리트윗을 받지 못하는 사용자의 노출도는 매우 미미하다는 것을 알 수 있었다. 위와 같은 사실은 노출도를 높이기 위해서는 실제 유력자도 중요하지만 그런 유력자의 리트윗을 유도하는 사용자의 파악이 더 중요하다는 점을 시사해준다고 볼 수 있다. 이와 함께 노출도의 경우 대부분의 중앙성 척도와 고른 상관관계를 유지하고 있어 노출도가 높은 이용자일수록 네트워크구조상에서도 중심적인 위상을 차지한다는 점도 살펴볼 수 있었다. The role of influentials to maximize word-of-mouth effect can be seen to be very important. In this paper, we have the perspective of corporate marketing to understand Twitter influentials. We start from the point of view of who can induce eventually most exposure of tweets when he tweets the companys specific marketing messages. From this perspective, we observe both the follower influentials who have many followers and the retweet influentials who induce many retweets by visualizing graphs from network data collected via Twitter Search API. Although some users have small followers they may bring much more exposure than follower influentials if they can induce retweets by follower influentials. On the contrary, some retweet influentials who dont induce retweets by follower influentials may bring very little exposure. This suggests the fact that some small users who can induce retweets by influentials might have more important role than influentials themselves in order to increase the exposure of tweets. These users also are seen to have high centrality measures in the network structure.

인터넷 불법복제에 따른 독점기업의 가격전력

유병국(Byong-kook Yoo) 한국인터넷전자상거래학회 2010 인터넷전자상거래연구 Vol.10 No.2

This study discusses on a pricing strategy of a monopoly when illegal copies of its information goods utilize Internet file-sharing technologies. Generally, the monopoly wants enforcement of copyright law in order to prevent sales loss by unauthorized reproduction of intellectual property. But strict law enforcement is not always profitable to monopoly. It is desirable to conduct an appropriate price strategy according to the market conditions changed by the copyright law enforcement by government. Under the situation that legal users increase through strict copyright enforcement, price increasing strategy could be profitable. However, there is some enforcement level above which some reproduction users may even give up using the product rather than buy it. In this case, price decreasing strategy that can lead them switch from copies to the originals is more desirable with strict copyright enforcement.