• Title/Summary/Keyword: Sampling Strategy

Search Result 410, Processing Time 0.029 seconds

Response Modeling for the Marketing Promotion with Weighted Case Based Reasoning Under Imbalanced Data Distribution (불균형 데이터 환경에서 변수가중치를 적용한 사례기반추론 기반의 고객반응 예측)

  • Kim, Eunmi;Hong, Taeho
    • Journal of Intelligence and Information Systems
    • /
    • v.21 no.1
    • /
    • pp.29-45
    • /
    • 2015
  • Response modeling is a well-known research issue for those who have tried to get more superior performance in the capability of predicting the customers' response for the marketing promotion. The response model for customers would reduce the marketing cost by identifying prospective customers from very large customer database and predicting the purchasing intention of the selected customers while the promotion which is derived from an undifferentiated marketing strategy results in unnecessary cost. In addition, the big data environment has accelerated developing the response model with data mining techniques such as CBR, neural networks and support vector machines. And CBR is one of the most major tools in business because it is known as simple and robust to apply to the response model. However, CBR is an attractive data mining technique for data mining applications in business even though it hasn't shown high performance compared to other machine learning techniques. Thus many studies have tried to improve CBR and utilized in business data mining with the enhanced algorithms or the support of other techniques such as genetic algorithm, decision tree and AHP (Analytic Process Hierarchy). Ahn and Kim(2008) utilized logit, neural networks, CBR to predict that which customers would purchase the items promoted by marketing department and tried to optimized the number of k for k-nearest neighbor with genetic algorithm for the purpose of improving the performance of the integrated model. Hong and Park(2009) noted that the integrated approach with CBR for logit, neural networks, and Support Vector Machine (SVM) showed more improved prediction ability for response of customers to marketing promotion than each data mining models such as logit, neural networks, and SVM. This paper presented an approach to predict customers' response of marketing promotion with Case Based Reasoning. The proposed model was developed by applying different weights to each feature. We deployed logit model with a database including the promotion and the purchasing data of bath soap. After that, the coefficients were used to give different weights of CBR. We analyzed the performance of proposed weighted CBR based model compared to neural networks and pure CBR based model empirically and found that the proposed weighted CBR based model showed more superior performance than pure CBR model. Imbalanced data is a common problem to build data mining model to classify a class with real data such as bankruptcy prediction, intrusion detection, fraud detection, churn management, and response modeling. Imbalanced data means that the number of instance in one class is remarkably small or large compared to the number of instance in other classes. The classification model such as response modeling has a lot of trouble to recognize the pattern from data through learning because the model tends to ignore a small number of classes while classifying a large number of classes correctly. To resolve the problem caused from imbalanced data distribution, sampling method is one of the most representative approach. The sampling method could be categorized to under sampling and over sampling. However, CBR is not sensitive to data distribution because it doesn't learn from data unlike machine learning algorithm. In this study, we investigated the robustness of our proposed model while changing the ratio of response customers and nonresponse customers to the promotion program because the response customers for the suggested promotion is always a small part of nonresponse customers in the real world. We simulated the proposed model 100 times to validate the robustness with different ratio of response customers to response customers under the imbalanced data distribution. Finally, we found that our proposed CBR based model showed superior performance than compared models under the imbalanced data sets. Our study is expected to improve the performance of response model for the promotion program with CBR under imbalanced data distribution in the real world.

Exploratory Study on the Phenomenon of Technology Transfer in Livestock Industry Based on the Grounded Theory Approach: Backward Linkage Industries in Livestock Industry (근거이론 접근법을 이용한 축산업분야 기술이전현상에 관한 탐색연구: 후방연관산업을 중심으로)

  • Seol, Byung Moon;Park, Jong Bok
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
    • /
    • v.11 no.1
    • /
    • pp.97-108
    • /
    • 2016
  • The competition between countries became internationalized in the market. However, a situation in which globalization is concerned is important to domestic corporates. Corporate strategy to survive in the domestic market are also juggling the limit of survival. Technology transfer and commercialization at this point has important implications now. The same applies to the national level. Public-to-private technology transfer has been more important, in order to overcome the international competitions. Although various studies have been made to promote technology transfer, in the livestock sector rarely attempted. Taking into account that few previous research and theory development has been achieved, the paper explored the technology transfer phenomenon in the sector employing the grounded theory approach by Strauss & Corbin(1998). Corporates that licensed in technologies through the Foundation of Agri. Tech. Commercialization & Transfer, were targeted as informants or interviewees. Finally, eight informants were selected sequentially utilizing theoretical sampling technique to the saturation point. As the result of open coding and axial coding of the interview data using NVivo10 by QSR International, 77 concepts, 20 sub-categories, and 7 categories were derived while paradigm model was established. Through selective coding, 'the factors affecting technology transfer in livestock sector' was identified as core category. The story line about the core category was developed based on four main categories. Finally, it is expected that the concepts, categories, and the relationship between them can be an important basis for further research.

  • PDF

Investigation on Physical Habitat Condition and Fish Fauna in Dal Stream of Han River Basin (한강수계 달천의 어류상과 물리적 서식지 조건에 관한 연구)

  • Hur, Jun-Wook;Kang, Hyoeng-Sik;Jang, Min-Ho
    • Journal of Korean Society of Environmental Engineers
    • /
    • v.33 no.8
    • /
    • pp.564-571
    • /
    • 2011
  • In order to establish fundamental data for stream restoration and environmental flow, we investigated fish fauna, community and physical habitat conditions in the Dal Stream of Han River Basin. Field monitoring including fish sampling was conducted from September 2008 to October 2009. A total number of fish caught in the 5 sites was 2,080 representing 9 families 35 species, and 19 species (54.3%) including Acheilognathus koreensis and Iksookimia koreensis were Korean endemic species during the study period. The most frequently found species in number was pale chub (Zacco platypus, 25.7%, n = 632) followed by Coreoleuciscus splendidus (18.0%, n = 375) and Z. koreanus (13.0%, n = 272). The lower reach of Dal Stream was more abundance of species, high diversity, evenness and richness, and lower dominance index than those of the upper reach. According to the dendrogram established at 0.63 level of similarity rate, sampling stations were divided into 2 groups. Most of upper streams in Korea consist of riffles and runs that are repeatedly followed by another one. However, stream channelization and leveling have caused reduction of habitat diversity. Therefore, it is necessary to make an effort on stream rehabilitation with evaluation of physical habitat condition by indicator species in order to maintain biodiversity and perform ecological restoration.

Prospective validation of a novel dosing scheme for intravenous busulfan in adult patients undergoing hematopoietic stem cell transplantation

  • Cho, Sang-Heon;Lee, Jung-Hee;Lim, Hyeong-Seok;Lee, Kyoo-Hyung;Kim, Dae-Young;Choe, Sangmin;Bae, Kyun-Seop;Lee, Je-Hwan
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.20 no.3
    • /
    • pp.245-251
    • /
    • 2016
  • The objective of this study was to externally validate a new dosing scheme for busulfan. Thirty-seven adult patients who received busulfan as conditioning therapy for hematopoietic stem cell transplantation (HCT) participated in this prospective study. Patients were randomized to receive intravenous busulfan, either as the conventional dosage (3.2 mg/kg daily) or according to the new dosing scheme based on their actual body weight (ABW) ($23{\times}ABW^{0.5}mg\;daily$) targeting an area under the concentration-time curve (AUC) of $5924{\mu}M{\cdot}min$. Pharmacokinetic profiles were collected using a limited sampling strategy by randomly selecting 2 time points at 3.5, 5, 6, 7 or 22 hours after starting busulfan administration. Using an established population pharmacokinetic model with NONMEM software, busulfan concentrations at the available blood sampling times were predicted from dosage history and demographic data. The predicted and measured concentrations were compared by a visual predictive check (VPC). Maximum a posteriori Bayesian estimators were estimated to calculate the predicted AUC ($AUC_{PRED}$). The accuracy and precision of the $AUC_{PRED}$ values were assessed by calculating the mean prediction error (MPE) and root mean squared prediction error (RMSE), and compared with the target AUC of $5924{\mu}M{\cdot}min$. VPC showed that most data fell within the 95% prediction interval. MPE and RMSE of $AUC_{PRED}$ were -5.8% and 20.6%, respectively, in the conventional dosing group and -2.1% and 14.0%, respectively, in the new dosing scheme group. These findings demonstrated the validity of a new dosing scheme for daily intravenous busulfan used as conditioning therapy for HCT.

A Study of academic high school students' STEM career motivation formation: An approach based on the Grounded Theory (고등학생들의 이공계 진로동기 형성과정 연구: 근거이론적 접근)

  • Jung, Young-Hee;Shin, Sein;Lee, Jun-Ki
    • Journal of Science Education
    • /
    • v.41 no.1
    • /
    • pp.36-59
    • /
    • 2017
  • The purpose of this study was to develop a theory appropriate to the context by identifying the career motivation formation process from the perspective of academic high school students using a grounded theory approach. In this study, participants were selected among non probability sampling was used for sampling by artificially reputational case selection methods. Forty two highschool students(21 male, 21 female) were participated in this study. Research data were collected mainly collected using in-depth interview data were analyzed by applying the grounded theory method of Strauss and Corbin (1998). According to the results, 319 concepts and 56 sub-categories, and 19 categories were derived n the open coding process. Academic high school students' formation of STEM career motivation were influenced by contextual conditions of "STEM-related career think that the instruments' causal conditions and 'STEM education experience in inside and outside of school' named 'STEM career understanding and self-understanding' using the strategy of being influenced in interventional conditions of social support and obstacle 'for the central phenomenon of "STEM efforts to achieve career goals, it appeared as a result of" satisfaction for STEM careers. And it had a 5-step process over time that the formation process of STEM career motivation. This is expected to provide homes, schools, communities, and contribute to have a new insight on the education of the country, given the direction of career education and counseling intervention and the basic data used to develop and apply STEM career education.

A Study on the Current Status and Improvement of Condition Assessment for Paper-Based Records in Domestic and Overseas (국내외 종이기록물 상태검사 현황과 개선 방안)

  • Lee, Jae-Young;Ahn, Kyujin;Moon, Hyun-Sook;Kwag, Jeong
    • Journal of Korean Society of Archives and Records Management
    • /
    • v.21 no.4
    • /
    • pp.117-135
    • /
    • 2021
  • Condition assessment of analog records is enforced to establish a preservation strategy and identify the damaged records by the Public Records Management Act and the public standard in Korea. However, the number of record management organizations where the condition assessment according to the act and the standard are actually conducted is limited in Korea. To find out what to change in the system and the practice of the condition assessment, the system and situation on the condition assessment of the paper-based records in Korea and other countries were investigated through literature research and a survey. Whereas Korean archives try to assess entire individual records, archives and libraries overseas apply condition assessment selectively depending on not only historical and cultural values of the records but also the vulnerability of compositional materials and severity of the damage of the records. It seems that archives and libraries overseas have a specific reason to conduct the assessment. Most of them take advantage of a sampling method not assessing every single item. Moreover, the periodical assessment is carried out in only about 50% of the responses. Therefore, we have to consider changing our condition assessment system to a more efficient and flexible way, adopting a sampling method and applying the assessment for selective collections with more specific purposes.

Assessing the Applicability of Hysteresis Indices for the Interpretation of Suspended Sediment Dynamics in a Forested Catchment (산림유역의 부유토사 동태 해석을 위한 이력현상 지수의 적용성 평가)

  • Ki-Dae Kim;Su-Jin Jang;Soo-Youn Nam;Jae-Uk Lee;Suk-Woo Kim
    • Korean Journal of Environment and Ecology
    • /
    • v.38 no.2
    • /
    • pp.178-188
    • /
    • 2024
  • The dynamics of suspended sediment (SS) in forested catchments vary depending upon human or natural disturbances, including land use change, forestry activity, forest fires, and landslides. Understanding the dynamics of SS originating from the potential sources within a forested catchment is crucial for establishing an effective water quality management strategy. Therefore, to suggest a systematic method for interpreting SS dynamics, we evaluated the performance and applicability of ten methods for calculating the hysteresis index based on observed hydrological data and two calculation models (Lawler's method and Lloyd's method) with five sampling intervals (50th, 25th, 10th, 5th, and 1st percentiles). Our results showed that Lloyd's method, which used a sampling interval at the 1st percentile, had the largest number of analyzable runoff events and exhibited the best performance. The results of this study can contribute to quantifying the hysteresis in the relationship between discharge and SS and provide useful information for interpreting SS dynamics.

A study on the Dining-out preference and behavior of consumers for the chilled meat consumption strategy in Seoul-Kyunggi Area (냉장육 소비전력을 위한 소비자 외식 기호도 연구 -서울, 경기지역을 중심으로-)

  • Bai, Young-Hee;Hwang, Dae-Ha
    • Journal of the Korean Society of Food Culture
    • /
    • v.13 no.3
    • /
    • pp.169-182
    • /
    • 1998
  • This study was conducted to investigate the consumers' Dining-out preference and behavior for the chilled meat consumption strategy . A total of 328 persons in Seoul, Kyunggi areas were selected by stratified random sampling method and were responded to this study questionnaire which was composed of six parts with 65 statements about chilled meat consumption. 1. The frequency of Dining-out is characterized that 'once a month' is the highest pattern of consumers(46.3%) : In that cases, the married people showed 'once a month'(52.7%) and 'once biweekly'(23.3%), but the unmarried people showed the more frequent pattern as 'once a week'(27.3%) and 'twice a week'(27.3%). And the frequency of Dining-out in relation with the education level revealed that 'the graduate people' are the highest (37.5%). 2. Generally the first food for the Dining-out is 'Kalbi'(26.2%), and the others were 'pork grilling','chilled meat grilling','fish sasimi','chinese foods','pizza' etc.... But there were some variation in relation with incomes and housing types: For the agriculture/physical labor class, they prefers the 'pork griling'(25.0%), the office work class prefers the 'Kalbi' For the house-owner group, they prefers the 'Kalbi', but the house-renting/lodging group, they prefer the 'chinese food' or 'pork grilling' etc.... 3. In choosing the Dining-out place,'quality of food'(54.3%) and 'hygiene'(21.0%) were rated as the first important factor. 4.'Soups', 'Noodles' and 'Cooked rice in casserole' were chosen as good lunch menu : for male, they prefer the 'Soups', but females prefer 'Cooked rice in casserole'. 5. People with commercials/services(44.7%) and agriculture/physical labor(50.0%) ate their lunch in private restaurant, but peoples in the office work(57.0%)/public service personnel(70.4%) and industry use refectory; and it showed significant difference. 6. Consumers prefer the chilled meat as a Dining-out menu, but they didn't recognize the difference between chilled meat and frozen meat 7. For Dining-out menu, many people proper the beef, but the price of beef was so high than pork, agriculture/physical labor class choose the pork grilling instead of beef : commercials/services/office worker prefer the beef chilled meat . 8. The first admirable cooking method for chilled meat is direct radiation grilling with charcoal and many of consumers prefer tender, marbling, some chewy and juicy, flavor, soft as a quality of meat but physical labor class prefer the some tough and chewy texture.

  • PDF

Analyzing the Spatial Change of Urban Green Spaces with Cell Based Spatial Metrics : A Case Study of Daegu (화소 기반 공간메트릭스를 이용한 도시 녹지의 공간적 변화 분석: 대구시를 사례로)

  • Seo, Hyun-Jin;Jun, Byong-Woon
    • Journal of the Korean association of regional geographers
    • /
    • v.23 no.1
    • /
    • pp.136-150
    • /
    • 2017
  • This study analyzed the spatial change of urban green spaces in Daegu from 1989 to 2009 using cell based spatial metrics. To do so, the conversion process of land covers during the past 20 years was explored using a land cover change detection matrix. The synoptic analysis with a moving window sampling strategy was conducted to quantify cell based spatial metrics related to size, shape, cohesion, and diversity and to explain the spatial change at the local level. Difference maps were then generated by subtracting the 1989 maps of spatial metrics from the 1998 maps and the 1998 maps from the 2009 maps. The gradient analysis was performed to identify the directional change of spatial metrics along an urban development axis in Daegu. The results from this study show that urban green spaces in Daegu during the past 20 years have been gradually fragmented around the new town housing development districts such as Dalseong-gun, Seongseo, and Ansim. Forests were most prominently fragmented in the Hwawon area while most rapidly in the Chilgok area. Grasslands were largely fragmented in many areas due to the decrease in size and cohesion indices and most fragmented in the Ansim area. The spatial pattern of the decreased and fragmented urban green spaces identified by this study can be used as a base data for establishing the environment-friendly urban development strategy in Daegu.

  • PDF

Internet Marketing Strategy and Performance in the Korean Small Export Firms (한국 중소수출기업의 인터넷 마케팅 전략과 성과에 관한 연구)

  • Ko, Kyung-Sun
    • International Commerce and Information Review
    • /
    • v.4 no.1
    • /
    • pp.107-128
    • /
    • 2002
  • In order to clarify the relationship between the Internet utilization of the Korean small export firms for export marketing and it's performance, first, a research model and hypothesis have been made on a theoretical basis. This research hypothesis has been examined through gathering survey data and a statistical analysis based on MANOVA. The conclusion, as well as the main point of this thesis, is that, in most cases, there was a significant statistical connection between the variables of export performances and Internet-utilized export marketing strategies, which are both based on the classical AIDA model of effective hierarchy of communication for sales and advertising. This conclusion brings forth a substantial topic as well as provides meaningful implications for the Korean small export firms when putting together a marketing strategy using the Internet. It is also hoped that this will come as a reference for other researchers henceforth. However, there is an issue of lack of representativeness when considering that the samples were chosen on the basis of the convenience sampling method. Another issue may be that a portion of the subjects were not related to actual trade, but were, in fact, Web masters who operated e-trade systems. Furthermore, there are also numerous problems of missing data, and 6 out of the 8 main hypotheses possessed the issue of fitness level with the data. Therefore, in order to enhance both the representative and fitness levels of the data of further research for this topic, future respondents will have to have special trade knowledge, as well as technical knowledge of e-trade. However, unless the Internet begins to greatly contribute to export marketing of corporations, this type of enterprising spirit by corporations in gathering suitable respondents will not surface. Although not used in examining the hypotheses of this particular thesis, the relationship between competitive and circumstantial variables, which were added to the upcoming survey, and export performances will soon be analyzed and announced in order to atone for some of the standards this thesis fell short of.

  • PDF