• Title/Summary/Keyword: WESML

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Estimation of Logistic Regression for Two-Stage Case-Control Data (2단계 사례-대조자료를 위한 로지스틱 회귀모형의 추론)

  • 신미영;신은순
    • The Korean Journal of Applied Statistics
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    • v.13 no.2
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    • pp.237-245
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    • 2000
  • In this paper we consider a logistic regression model based on two-stage case-control sampling and study the Weighted Exogeneous Sampling Maximum Likelihood(WESML) method to get an asymptotically normal estimates of the parameters in a logistic regression model. A numerical example is carried out to demonstrate the differences between the Conditional Maximum Likelihood(CML) estimates and the WESML estimates for two-stage case-control data.

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Logistic Regression for Retrospective Studies

  • Shin, Mi-Young
    • Journal of Korean Society for Quality Management
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    • v.22 no.4
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    • pp.111-119
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    • 1994
  • We consider logistic models based on retrospective, case-control data with stratified samples and study the Weighted Exogeneous Sampling Maximum Likelihood (WESMU) We develop a consistent estimator of the asymptotic covariance matrix of the WESML estimator.

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Dynamic Model Considering the Biases in SP Panel data (SP 패널데이터의 Bias를 고려한 동적모델)

  • 남궁문;성수련;최기주;이백진
    • Journal of Korean Society of Transportation
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    • v.18 no.6
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    • pp.63-75
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    • 2000
  • Stated Preference (SP) data has been regarded as more useful than Revealed Preference (RP) data, because researchers can investigate the respondents\` Preference and attitude for a traffic condition or a new traffic system by using the SP data. However, the SP data has two bias: the first one is the bias inherent in SP data and the latter one is the attrition bias in SP panel data. If the biases do not corrected, the choice model using SP data may predict a erroneous future demand. In this Paper, six route choice models are constructed to deal with the SP biases, and. these six models are classified into cross-sectional models (model I∼IH) and dynamic models (model IV∼VI) From the six models. some remarkable results are obtained. The cross-sectional model that incorporate RP choice results of responders with SP cross-sectional model can correct the biases inherent in SP data, and also the dynamic models can consider the temporal variations of the effectiveness of state dependence in SP responses by assuming a simple exponential function of the state dependence. WESML method that use the estimated attrition probability is also adopted to correct the attrition bias in SP Panel data. The results can be contributed to the dynamic modeling of SP Panel data and also useful to predict more exact demand.

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