• The Korean Journal of Applied Statistics
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• v.6 no.2
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• pp.393-399
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• 1993

When we compute the maximum likelihood estimators of the parameters for the logistic regression models, which are useful in studying the relationship between the binary response variable and the explanatory variable, the standard error calculations are usually based on the second derivative of log-likelihood function. On the other hand, an estimator of the Fisher information motivated from the fact that the expectation of the cross-product of the first derivative of the log-likelihood function gives the Fisher information is expected to have similar asymptotic properties. These estimators of Fisher information are closely related with the iterative algorithm to get the maximum likelihood estimator. The average numbers of iterations to achieve the maximum likelihood estimator are compared to find out which method is more efficient, and the estimators of the variance from each method are compared as estimators of the asymptotic variance.

• The Korean Journal of Applied Statistics
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• v.32 no.5
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• pp.653-669
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• 2019

The development of new media has gradually decreased the use of newspapers, which had previously occupied the largest share of media. Subscriptions have declined gradually and fell to 14 percent in 2016. This study explores the effects of Newspaper reader's characteristics on regular newspaper subscriptions. The data used for analysis was provided by the Korean Press Foundation and Media Audience Awareness Survey Data in 2016 and 2017. We considered gender, age, education, income, number of days of reading, reading time and amount of reading as the characteristics of the reader. Multiple logistic regression was fitted and interpreted to see what characteristics affect regular subscription.

• The Korean Journal of Applied Statistics
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• v.35 no.2
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• pp.311-325
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• 2022

For count responses, the situation of excess zeros often occurs in various research fields. Zero-inflated model is a common choice for modeling such count data. Bayesian inference for the zero-inflated model has long been recognized as a hard problem because the form of conditional posterior distribution is not in closed form. Recently, however, Pillow and Scott (2012) and Polson et al. (2013) proposed a Pólya-Gamma data-augmentation strategy for logistic and negative binomial models, facilitating Bayesian inference for the zero-inflated model. We apply Bayesian zero-inflated negative binomial regression model to longitudinal pharmaceutical data which have been previously analyzed by Min and Agresti (2005). To facilitate posterior sampling for longitudinal zero-inflated model, we use the Pólya-Gamma data-augmentation strategy.

• Communications for Statistical Applications and Methods
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• v.15 no.6
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• pp.859-873
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• 2008

Job satisfaction impacts on the turnover intention of employee, which affects the turnover behavior. This paper concerns with the impact of job satisfaction on the turn over behavior. Since turnover intention is highly correlated with job satisfaction, salary, employment status and etc, we should pay careful attention for modelling of those variables as independent variables and the turnover behavior as a dependent variable in the empirical study for the impact of factors on turnover behavior. We detect significant variables which effect the turnover behavior using 2-stage logistic regression inserting the turnover intention, an independent variable, with the chance estimates derived from the instrumental variables in Graduates Occupational Mobility Survey.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.10
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• pp.997-1004
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• 2017

The life of elevator wire ropes is one of the most important characteristics of an elevator, which is closely related to the safety of users and its maintenance policy. It is not cost effective to measure the lifetime of elevator wire ropes during their use. In this study, the life estimation of elevator wire ropes (8x19W-IWRC) is considered using accelerated degradation test data. A bending fatigue tester is used to perform the accelerated degradation tests, incorporating the acceleration factor of tensile force. Assuming that the life of wire ropes is log-normally distributed, two life estimation methods are suggested and their results are compared. The first method estimates the life of wire ropes utilizing the accelerated life model with pseudo lives obtained from a linear regression model. The second method estimates the life using a logistic model based on failure probability.

• The Journal of Society for e-Business Studies
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• v.23 no.1
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• pp.47-63
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• 2018

This study suggested quantitative models to calculate a royalty rate as an important input factor of the relief from royalty method which has the characteristics of income approach method and market approach method that are generally used in the valuation of intangible assets. This study built a royalty rate regression model by referring to the patent infringement damages cases based on royalties, i.e., by using the royalty rates as a dependent variable and the patent indexes of the corresponding patent right as independent variables. Then, a logistic regression model was constructed by referring to inter-partes review cases of patent rights, i.e. by using not-unpatentable results as a dependent variable and the patent indexes of the corresponding patent right as independent variables. A final royalty rate was calculated by matching the royalty rate from the royalty rate regression model with a not-unpatentable probability from the logistic regression model. The suggested royalty rate was compared with the royalty rate obtained by the traditional methods to check its reliability.

• Proceedings of the Korean Statistical Society Conference
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• 2003.05a
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• pp.7-12
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• 2003

문항반응이론(IRT)에서 문항특성곡선(ICC)의 모수를 추정하는 경우에 발생되는 초기값(initial value) 문제를 비선형 로지스틱모형을 선형 회귀모형으로 근사화하여 해결하고자 하였다. 특히, 신규 또는 잡음이 섞인(local fluctuation) 문항의 직접적인 평가와 소규모집단별 검사가 이루어질 수 있는 현실적 문제에서 모수추정의 대안으로서 그 의의가 있을 수 있다.

• Water for future
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• v.54 no.7
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• pp.53-60
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• 2021

• Journal of Korean Society of Forest Science
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• v.101 no.1
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• pp.1-6
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• 2012

To achieve the forest fire management goals such as early detection and quick suppression, fire resources should be allocated at high probability area where forest fires occur. The objective of this study was to develop and validate models to estimate spatially distributed probabilities of occurrence of forest fire. The models were builded by exploring relationships between fire ignition location and forest, terrain and anthropogenic factors using logistic regression. Distance to forest, cemetery, fire history, forest type, elevation, slope were chosen as the significant factors to the model. The model constructed had a good fit and classification accuracy of the model was 63%. This model and map can support the allocation optimization of forest fire resources and increase effectiveness in fire prevention and planning.

• Journal of Korean Academy of Nursing
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• v.51 no.1
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• pp.40-53
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• 2021

Purpose: The purpose of this study was to develop and compare the prediction model for suicide attempts by Korean adolescents using logistic regression and decision tree analysis. Methods: This study utilized secondary data drawn from the 2019 Youth Health Risk Behavior web-based survey. A total of 20 items were selected as the explanatory variables (5 of sociodemographic characteristics, 10 of health-related behaviors, and 5 of psychosocial characteristics). For data analysis, descriptive statistics and logistic regression with complex samples and decision tree analysis were performed using IBM SPSS ver. 25.0 and Stata ver. 16.0. Results: A total of 1,731 participants (3.0%) out of 57,303 responded that they had attempted suicide. The most significant predictors of suicide attempts as determined using the logistic regression model were experience of sadness and hopelessness, substance abuse, and violent victimization. Girls who have experience of sadness and hopelessness, and experience of substance abuse have been identified as the most vulnerable group in suicide attempts in the decision tree model. Conclusion: Experiences of sadness and hopelessness, experiences of substance abuse, and experiences of violent victimization are the common major predictors of suicide attempts in both logistic regression and decision tree models, and the predict rates of both models were similar. We suggest to provide programs considering combination of high-risk predictors for adolescents to prevent suicide attempt.