• The Korean Journal of Applied Statistics
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• v.27 no.6
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• pp.923-932
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• 2014

The Hurdle model can to analyze zero-inflated count data. This model is a mixed model of the logit model for a binary component and a truncated Poisson model of a truncated count component. We propose a new hurdle model with a general heterogeneous random effects covariance matrix to analyze longitudinal zero-inflated count data using modified Cholesky decomposition. This decomposition factors the random effects covariance matrix into generalized autoregressive parameters and innovation variance. The parameters are modeled using (generalized) linear models and estimated with a Bayesian method. We use these methods to carefully analyze a real dataset.

• Journal of Korean Society of Rural Planning
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• v.21 no.2
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• pp.137-147
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• 2015

In this study, consumers who have experience of visiting Jeongsun Arirang Market has been selected as samples to understand the characteristics of agricultural products purchase. For this, double hurdle model was used in order to resolve sample selection problem and obtain consistent estimator. The key points are the following. First, as the age increases(up to 59.8 years), chances of purchasing the products at traditional market increase as income increases. Second, when the residence area is outside of Gangwon-province, the purchase amount of the products increased compared to those from visitors within the Gangwon province. Also, visitors who use public transportations purchase less products compared to those who use their own car. Third, probability of agricultural products increase as the visitors consider positive effect the product purchase leads to the local farmers. Fourth, if the visitors consider the quality of the agricultural products, probability of purchasing agricultural product at the site increases. However, if the visitors consider the freshness of the agricultural products, the purchase amount rather drops. Fifth, the probability of purchase increases as visitors consider the brand of traditional market.

• Journal of Korea Technology Innovation Society
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• v.17 no.3
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• pp.449-466
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• 2014

There have been various researches on the relationship between a company's R&D investment and the outcome from innovation. However, these studies failed to effectively analyze the decision-making process followed by companies in relation to knowledge production. Especially, in analyzing the patent of companies, the Poisson model has been commonly used, but its limitations have been pointed out. In recent years, many studies have adopted negative binomial models, but they still pose limitations in analyzing the selection process. This paper proposed a hurdle negative binomial model to effectively reflect the company's decision embedded within patent information and conduct an empirical analysis on a survey of businesses' activities. In particular, the study analyzed the selection process of companies in determining the number of patents. As a result of estimation, the presence of over-dispersion was identified. In addition, the Wald-test confirmed that setting up of hurdles was valid, and there was a difference between the results of hurdle models and those of general negative binomial settings.

• The Journal of Fisheries Business Administration
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• v.34 no.2
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• pp.131-139
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• 2003

The products of the quality certificated fisheries which are protected from environmental pollution, decomposition are hygienically safe and convenient for food. However, consumers have not yet understood the recognition of the system of quality certfication so far because of lack of demand on the quality certification fisheries. Above all, to put the system of the quality QC in place sucessfully, to understand the variation of consumer's inclination efficiently, the empirical study must be carried out by both consumer's take part in the market of the quality certificated fisheries products and how much the amount of consumption is in this market. The purpose of this study, under the preconditions where these have limited fisheries items in consumer's inclination survey, is to analyze the demand of QC though the Double Hurdle Model. Explanatory variables included were household characteristics such as housewives' age and education, her job, household income as well as their health perceptions and food purchase behaviors. Survey from 530 household was collected in Pusan City in 2003, of 502 were actually used for empirical analysis. The Double-hurdle framework proved to a better representation of the factors influencing the separate decision participation and consumption levels. According to the results of this study, whether or not, participating In the market of quality certicipating in the market of qualify certificated fisheries products is affected by how much experience and confidence these have got. housewives' having a job or not. Furthermore, the amount of consumption is mostly affected income. This value is attributed to the safety of QC fisheries products in comparison with regular fisheries. Findings suggest that the consumers put substantially high monetary value on safe food, such as high quality fisheries products. Therefore, first of all, legal and institutional systems should be clearly and strictly identified for the QC products.

• International journal of advanced smart convergence
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• v.11 no.3
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• pp.162-169
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• 2022

The purpose of this study is to estimate the determinants of the smoking demands of university students. For this study, a total of four four-year universities and two-year colleges in Seoul and provincial areas were surveyed. The model for analyzing the demand for smoking was applied with a double hurdle model, and determinants to participate in smoking in the first stage and the amount of smoking in the second stage were analyzed. According to the analysis results, the determinants to participate in smoking as a first stage are gender, grade, college type, major category, and parents' income, which have a statistically significant effect, and the analysis of the amount of smoking as a second has been analyzed as the variables that influence gender, grade, college location, major, parents' income type and income amount.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.10
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• pp.76-91
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• 2019

There have been many studies to examine the patterns in innovations reflecting industry-specific characteristics from an evolutionary economics perspective. The purpose of this study is to identify industry-specific differences in product innovation patterns and determinants of innovation performance. For this, Korean manufacturing is classified into high-tech industries and low-tech industries according to technology intensity. It is also pointed out that existing research does not reflect the decision-making process of firms' R&D implementations. In order to solve this problem, this study presents a Heckman sample selection model and a double-hurdle model as alternatives, and analyzes data from 1,637 firms in the 2014 Survey on Technology of SMEs. As a result, it was confirmed that the determinants and patterns of manufacturing in small and medium-size enterprise (SME) product innovation are significantly different between high-tech and low-tech industries. Also, through an extended empirical model, we found that there exist a sample selection bias and a hurdle-like threshold in the decision-making process. In this study, the industry-specific features and patterns of product innovation are examined from a multi-sided perspective, and it is meaningful that the decision-making process for manufacturing SMEs' R&D performance can be better understood.

• The Korean Journal of Applied Statistics
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• v.29 no.7
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• pp.1459-1473
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• 2016

Both longitudinal data and survival data are collected simultaneously in longitudinal data which are observed throughout the passage of time. In this case, the effect of the independent variable becomes biased (provided that sole use of longitudinal data analysis does not consider the relation between both data used) if the missing that occurred in the longitudinal data is non-ignorable because it is caused by a correlation with the survival data. A joint model of longitudinal data and survival data was studied as a solution for such problem in order to obtain an unbiased result by considering the survival model for the cause of missing. In this paper, a joint model of the longitudinal zero-inflated count data and survival data is studied by replacing the longitudinal part with zero-inflated count data. A hurdle model and proportional hazards model were used for each longitudinal zero inflated count data and survival data; in addition, both sub-models were linked based on the assumption that the random effect of sub-models follow the multivariate normal distribution. We used the EM algorithm for the maximum likelihood estimator of parameters and estimated standard errors of parameters were calculated using the profile likelihood method. In simulation, we observed a better performance of the joint model in bias and coverage probability compared to the separate model.

• Journal of the Korean Home Economics Association
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• v.41 no.5
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• pp.1-13
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• 2003

This study examined the determinants of urban households' expenditures on alcoholic beverages, using double-hurdle models to distinguish between the decision to purchase (purchase decision) and the decision of how much to consume (expenditure decision). Data for this study were drawn from the 2000 Korean Household Income and Expenditure Survey. Households were likely to purchase alcoholic beverages with increasing of household income, tobacco expenditures, and household size. The age, sex, marital status, occupation, education level, type of house ownership, residing city were significantly related to the purchase decisions. Among those households which drink, as household income and tobacco expenditures increase, the age, sex (male), marital status (married), and education level of a household-head, house ownership, residing city (Seoul) were positively related to and the presence of young children were negatively related to the expenditure level of alcoholic beverages.

• Information Systems Review
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• v.8 no.1
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• pp.159-179
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• 2006

With the advances in information technologies and the wide acceptance of IT outsourcing practices, subscription-based information & telecommunications services(ITS) become more available. Convergence and intensified industry competition have made it an imperative for the ITS providers to keep their current customers and acquire new customers at the same time. In this study, we developed a framework for effective customer management based on the factors influencing the post-purchase customer choice: stay with the present provider or switch to another one. Specifically, we classified the factors into four categories: Holding factors, Defect factors, Inducement factors, and Hurdle factors depending on the characteristics of the influence and direction of the influence. Based on the classification, we developed a post-purchase customer choice model for the subscription-based ITS providers. Then, we illustrated a possible application of the model in the context of the broadband Internet access service. The model could be used to increase the competitive advantage of service providers through the effective customer management in the subscription-based ITS market.

• Journal of Family Resource Management and Policy Review
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• v.8 no.1
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• pp.79-100
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• 2004

This study attempted to examine the employment instability on consumer's use of credit as a financing medium. The purpose of this study was 1) to examine the effect of employment related factors on consumers' use of credit; 2) to compare the results between the two different economic situations. A conceptual framework was developed based on the permanent income hypothesis, family stress theory, and the previous empirical studies. Using data on working households ih the 1992 and 1998 Survey of Consumer Finances (SCF), double-hurdle analyses were conducted. The results suggested that employment related factors that measured employment stability were significantly related to the likelihood of having an outstanding balance on their credit account but were not the influential factors in determining the amount of the outstanding balance. Among other factors, resources factor played the most significant role in determining both the likelihood of having an outstanding balance and the amount of the balance. Although the 1992 and 1998 data represent economic downturn and economic prosperous period, the effects of the factors including employment instability factors were similar between the two periods. This imply that employment instability has increased even in the economic prosperous period. From the findings, several implications for policy makers, credit industry, and financial educators were suggested.