• Title/Summary/Keyword: Multiple-Regression

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Validation of the Nursing Outcomes Classification (NOC) to Nursing in Korea (간호결과 분류체계의 타당성 검증 - 지역사회 간호결과를 중심으로 -)

  • Lee, Eun-Joo
    • Research in Community and Public Health Nursing
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    • v.13 no.3
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    • pp.523-531
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    • 2002
  • Purpose: The purpose of this study was to assess the importance and sensitivity to nursing interventions of six sensitive nursing outcomes selected from the Nursing Outcomes Classification. The outcomes in this study were Self-Care: Activities of Daily Living, Self-Care: Instrumental Activities of Daily Living, Treatment Behavior: Illness or Injury, Knowledge: Health Promotion, Caregiver Performance: Direct Care, and Caregiver Physical Health. Method: Data were collected from 97 visiting nurses working in public health centers located in a province and a capital city. The Fehring method was used to estimate outcomes and indicators for content validity. Simultaneous multiple regression and stepwise regression were used to evaluate relationships between each outcome and its indicators. Results: Results confirmed the importance and nursing sensitivity of the outcomes and their indicators. Multiple regression revealed key indicators of each outcome. Self-Care: Instrumental Activity of Daily Living needed to be revised. Neither all of the indicators nor the indicators showing the highest importance and contribution ratio were selected as independent variables for the stepwise regression model. The R2 of the regression models ranged from 29 to 56% in importance by selected indicators and from 56 to 83% in contribution. Conclusion: Further research is needed for the revision of outcomes and their indicators.

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Regression Quantile Estimations on Censored Survival Data

  • Shim, Joo-Yong
    • Journal of the Korean Data and Information Science Society
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    • v.13 no.2
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    • pp.31-38
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    • 2002
  • In the case of multiple survival times which might be censored at each covariate vector, we study the regression quantile estimations in this paper. The estimations are based on the empirical distribution functions of the censored times and the sample quantiles of the observed survival times at each covariate vector and the weighted least square method is applied for the estimation of the regression quantile. The estimators are shown to be asymptotically normally distributed under some regularity conditions.

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Clustering Observations for Detecting Multiple Outliers in Regression Models

  • Seo, Han-Son;Yoon, Min
    • The Korean Journal of Applied Statistics
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    • v.25 no.3
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    • pp.503-512
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    • 2012
  • Detecting outliers in a linear regression model eventually fails when similar observations are classified differently in a sequential process. In such circumstances, identifying clusters and applying certain methods to the clustered data can prevent a failure to detect outliers and is computationally efficient due to the reduction of data. In this paper, we suggest to implement a clustering procedure for this purpose and provide examples that illustrate the suggested procedure applied to the Hadi-Simonoff (1993) method, reverse Hadi-Simonoff method, and Gentleman-Wilk (1975) method.

VARIANCE ESTIMATION OF ERROR IN THE REGRESSION MODEL AT A POINT

  • Oh, Jong-Chul
    • Journal of applied mathematics & informatics
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    • v.13 no.1_2
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    • pp.501-508
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    • 2003
  • Although the estimate of regression function is important, some have focused the variance estimation of error term in regression model. Different variance estimators perform well under different conditions. In many practical situations, it is rather hard to assess which conditions are approximately satisfied so as to identify the best variance estimator for the given data. In this article, we suggest SHM estimator compared to LS estimator, which is common estimator using in parametric multiple regression analysis. Moreover, a combined estimator of variance, VEM, is suggested. In the simulation study it is shown that VEM performs well in practice.

Detection of Change-Points by Local Linear Regression Fit;

  • Kim, Jong Tae;Choi, Hyemi;Huh, Jib
    • Communications for Statistical Applications and Methods
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    • v.10 no.1
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    • pp.31-38
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    • 2003
  • A simple method is proposed to detect the number of change points and test the location and size of multiple change points with jump discontinuities in an otherwise smooth regression model. The proposed estimators are based on a local linear regression fit by the comparison of left and right one-side kernel smoother. Our proposed methodology is explained and applied to real data and simulated data.

Comparison of Behavior Patterns between First and Repeated Offenders in Driving While Intoxicated(DWI) (음주운전 초.재범자 특성 비교)

  • Jeong, Cheol-U;Jang, Myeong-Sun
    • Journal of Korean Society of Transportation
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    • v.27 no.3
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    • pp.149-160
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    • 2009
  • The purpose of this study is to comparatively analyse the behavior patterns of the first and the repeated offenders in DWI, and to develope the models of BAC(Blood Alcohol Concentration) by using multiple regression analysis method and a model of repeated DWI conviction by using logistic regression analysis method. The main results are as follows. First, the repeated offenders are more in criminal and traffic accidents records than that of the first offenders. The unlicenced drivers are in higher BAC than licenced drivers. Second, multiple regression model of BAC was developed, and the model revealed that criminal records and driving distance were important factors. Third, a model of repeated DWI conviction was developed, and the model revealed that traffic accidents records, whether or not having licence, and criminal records were most important factors.

Prediction Models of Residual Chlorine in Sediment Basin to Control Pre-chlorination in Water Treatment Plant (정수장 전염소 공정 제어를 위한 침전지 잔류 염소 농도 예측모델 개발)

  • Lee, Kyung-Hyuk;Kim, Ju-Hwan;Lim, Jae-Lim;Chae, Seon Ha
    • Journal of Korean Society of Water and Wastewater
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    • v.21 no.5
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    • pp.601-607
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    • 2007
  • In order to maintain constant residual chlorine in sedimentation basin, It is necessary to develop real time prediction model of residual chlorine considering water treatment plant data such as water qualities, weather, and plant operation conditions. Based on the operation data acquired from K water treatment plant, prediction models of residual chlorine in sediment basin were accomplished. The input parameters applied in the models were water temperature, turbidity, pH, conductivity, flow rate, alkalinity and pre-chlorination dosage. The multiple regression models were established with linear and non-linear model with 5,448 data set. The corelation coefficient (R) for the linear and non-linear model were 0.39 and 0.374, respectively. It shows low correlation coefficient, that is, these multiple regression models can not represent the residual chlorine with the input parameters which varies independently with time changes related to weather condition. Artificial neural network models are applied with three different conditions. Input parameters are consisted of water quality data observed in water treatment process based on the structure of auto-regressive model type, considering a time lag. The artificial neural network models have better ability to predict residual chlorine at sediment basin than conventional linear and nonlinear multi-regression models. The determination coefficients of each model in verification process were shown as 0.742, 0.754, and 0.869, respectively. Consequently, comparing the results of each model, neural network can simulate the residual chlorine in sedimentation basin better than mathematical regression models in terms of prediction performance. This results are expected to contribute into automation control of water treatment processes.

Development and Validation of Multiple Regression Models for the Prediction of Effluent Concentration in a Sewage Treatment Process (하수처리장 방류수 수질예측을 위한 다중회귀분석 모델 개발 및 검증)

  • Min, Sang-Yun;Lee, Seung-Pil;Kim, Jin-Sik;Park, Jong-Un;Kim, Man-Soo
    • Journal of Korean Society of Environmental Engineers
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    • v.34 no.5
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    • pp.312-315
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    • 2012
  • In this study, the model which can predict the quality of effluent has been implemented through multiple regression analysis to use operation data of a sewage treatment plant, to which a media process is applied. Multiple regression analysis were carried out by cases according to variable selection method, removal of outliers and log transformation of variables, with using data of one year of 2011. By reviewing the results of predictable models, the accuracy of prediction for $COD_{Mn}$ of treated water of secondary clarifiers was over 0.87 and for T-N was over 0.81. Using this model, it is expected to set the range of operating conditions that do not exceed the standards of effluent quality. In conclusion, the proper guidance on the effluent quality and energy costs within the operating range is expected to be provided to operators.

Construction of Urban Crime Prediction Model based on Census Using GWR (GWR을 이용한 센서스 기반 도시범죄 특성 분석 및 예측모델 구축)

  • YOO, Young-Woo;BAEK, Tae-Kyung
    • Journal of the Korean Association of Geographic Information Studies
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    • v.20 no.4
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    • pp.65-76
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    • 2017
  • The purpose of this study was to present a prediction model that reflects crime risk area analysis, including factors and spatial characteristics, as a precursor to preparing an alternative plan for crime prevention and design. This analysis of criminal cases in high-risk areas revealed clusters in which approximately 25% of the cases within the study area occurred, distributed evenly throughout the region. This means that using a multiple linear regression model might overestimate the crime rate in some regions and underestimate in others. It also suggests that the number of deserted houses in an analyzed region has a negative relationship with the dependent variable, based on the multiple linear regression model results, and can also have different influences depending on the region. These results reveal that closure signs in a study area affect the dependent variable differently, depending on the region, rather than a simple or direct relationship with the dependent variable, as indicated by the results of the multiple linear regression model.

A Multiple Regression Model for the Estimation of Monthly Runoff from Ungaged Watersheds (미계측 중소유역의 월유출량 산정을 위한 다중회귀모형 연구)

  • 윤용남;원석연
    • Water for future
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    • v.24 no.3
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    • pp.71-82
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    • 1991
  • Methods of predicting water resources availiability of a river basin can be classified as empirical formula, water budget analysis and regression analysis. The purpose of this study is to develop a method to estimate the monthly runoff required for long-term water resources development project. Using the monthly runoff data series at gaging stations alternative multiple regression models were constructed and evaluated. Monthly runoff volume along with the meteorological and physiographic parameters of 48 gaging stations are used, those of 43 stations to construct the model and the remaining 5 stations to verify the model. Regression models are named to be Model-1, Model-2, Model-3 and Model-4 developing on the way of data processing for the multiple regressions. From the verification, Model-2 is found to be the best-fit model. A comparison of the selected regression model with the Kajiyama's formula is made based on the predicted monthly and annual runoff of the 5 watersheds. The result showed that the present model is fairly resonable and convinient to apply in practice.

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