• 제목/요약/키워드: multiple regression function

검색결과 533건 처리시간 0.022초

다중회귀분석에 의한 하천 월 유출량의 추계학적 추정에 관한 연구 (A Study on Stochastic Estimation of Monthly Runoff by Multiple Regression Analysis)

  • 김태철;정하우
    • 한국농공학회지
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    • 제22권3호
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    • pp.75-87
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    • 1980
  • Most hydro]ogic phenomena are the complex and organic products of multiple causations like climatic and hydro-geological factors. A certain significant correlation on the run-off in river basin would be expected and foreseen in advance, and the effect of each these causual and associated factors (independant variables; present-month rainfall, previous-month run-off, evapotranspiration and relative humidity etc.) upon present-month run-off(dependent variable) may be determined by multiple regression analysis. Functions between independant and dependant variables should be treated repeatedly until satisfactory and optimal combination of independant variables can be obtained. Reliability of the estimated function should be tested according to the result of statistical criterion such as analysis of variance, coefficient of determination and significance-test of regression coefficients before first estimated multiple regression model in historical sequence is determined. But some error between observed and estimated run-off is still there. The error arises because the model used is an inadequate description of the system and because the data constituting the record represent only a sample from a population of monthly discharge observation, so that estimates of model parameter will be subject to sampling errors. Since this error which is a deviation from multiple regression plane cannot be explained by first estimated multiple regression equation, it can be considered as a random error governed by law of chance in nature. This unexplained variance by multiple regression equation can be solved by stochastic approach, that is, random error can be stochastically simulated by multiplying random normal variate to standard error of estimate. Finally hybrid model on estimation of monthly run-off in nonhistorical sequence can be determined by combining the determistic component of multiple regression equation and the stochastic component of random errors. Monthly run-off in Naju station in Yong-San river basin is estimated by multiple regression model and hybrid model. And some comparisons between observed and estimated run-off and between multiple regression model and already-existing estimation methods such as Gajiyama formula, tank model and Thomas-Fiering model are done. The results are as follows. (1) The optimal function to estimate monthly run-off in historical sequence is multiple linear regression equation in overall-month unit, that is; Qn=0.788Pn+0.130Qn-1-0.273En-0.1 About 85% of total variance of monthly runoff can be explained by multiple linear regression equation and its coefficient of determination (R2) is 0.843. This means we can estimate monthly runoff in historical sequence highly significantly with short data of observation by above mentioned equation. (2) The optimal function to estimate monthly runoff in nonhistorical sequence is hybrid model combined with multiple linear regression equation in overall-month unit and stochastic component, that is; Qn=0. 788Pn+0. l30Qn-1-0. 273En-0. 10+Sy.t The rest 15% of unexplained variance of monthly runoff can be explained by addition of stochastic process and a bit more reliable results of statistical characteristics of monthly runoff in non-historical sequence are derived. This estimated monthly runoff in non-historical sequence shows up the extraordinary value (maximum, minimum value) which is not appeared in the observed runoff as a random component. (3) "Frequency best fit coefficient" (R2f) of multiple linear regression equation is 0.847 which is the same value as Gaijyama's one. This implies that multiple linear regression equation and Gajiyama formula are theoretically rather reasonable functions.

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Outlier Identification in Regression Analysis using Projection Pursuit

  • Kim, Hyojung;Park, Chongsun
    • Communications for Statistical Applications and Methods
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    • 제7권3호
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    • pp.633-641
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    • 2000
  • In this paper, we propose a method to identify multiple outliers in regression analysis with only assumption of smoothness on the regression function. Our method uses single-linkage clustering algorithm and Projection Pursuit Regression (PPR). It was compared with existing methods using several simulated and real examples and turned out to be very useful in regression problem with the regression function which is far from linear.

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주부의 소비자기능과 관련변수간의 인과관계 (The Causal Relationship of Homemakers' Consumer Function and the Related Variables)

  • 김미라
    • 가정과삶의질연구
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    • 제17권3호
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    • pp.131-144
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    • 1999
  • The purpose of this study was to examine the influences of the consumer's knowledge the consumer's attitude the family characteristics and the variables on consumer socialization to the consumer's functions of homemakers. The samples were selected from 428 homemakers living in Kwangju, Frequncies Perentiles Means Standard Deviations Multiple regression Path analysis were used as statistical analysis The results were sumarized as follows: Resulting from multiple regression analysis the consumer's function had the positive linear relationships with variables such as family life cycles interaction with family consume knowledge and consumer attitude. The most influential variable was consumer attitude.

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청소년의 자아분화 수준 및 가족기능이 정신건강에 미치는 영향 (Effect of Self-differentiation and Family Function on Mental Health in Adolescents)

  • 이혜순
    • Child Health Nursing Research
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    • 제16권4호
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    • pp.297-303
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    • 2010
  • Purpose: The purpose of this study was to identify the relationship of self-differentiation, family function and mental health among adolescents. Methods: The data were collected from 967 adolescents and analyzed using descriptive statistics, t-test, ANOVA, Scheffe's test, Pearson correlation coefficient and Stepwise multiple regression with the SPSS program. Results: Mental health differed according to grades, sibling position, father's education and mother's education. Self-differentiation and family function had a significant negative correlation with mental health. Multiple regression analysis showed recognition.emotional function, emotional cutoff and family projection as influencing self-differentiation. Grades, affective responsiveness in family function, and sibling position explained 20.8% of the total variance in mental health. Conclusion: The findings show that self-differentiation and family function influence mental health, indicating a need to develop nursing intervention programs to enhance adolescents' mental health and prevent negative outcomes. For these programs, the family must be included.

청소년의 가족기능, 충동성, 스트레스 수준이 집단따돌림 유형에 미치는 영향 (Effects of Family Function, Impulsive Behavior and Stress on Bullying Types of Adolescents)

  • 이혜순
    • 한국콘텐츠학회논문지
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    • 제14권2호
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    • pp.319-329
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    • 2014
  • 본 연구는 청소년의 가족기능, 충동성, 스트레스가 집단따돌림 유형에 미치는 영향을 파악하기 위한 서술적 조사연구이다. 연구대상은 중 고등학생 627명으로, 수집된 자료는 SPSS 18.0 program을 사용하여 평균과 표준편차, t-test, Pearson's Correlation Coefficient 및 stepwise multiple regression analysis으로 분석하였다. 연구결과는 다음과 같다. 집단따돌림 유형(가해 및 피해)은 가족기능, 충동성, 스트레스와 상관관계가 있는 것으로 나타났다. 집단따돌림 가해에 영향을 미치는 요인은 가족기능의 하부요인에서 정서적 반응성, 충동성의 하부영역에서 무계획 충동성, 스트레스의 하부요인에서 친구관련 스트레스, 일반적 특성에서 음주경험(있음), 부모 우울문제 경험(있음)로 확인되었으며, 34.1%의 설명력을 나타내었다. 집단따돌림 피해에 영향을 미치는 요인은 가족기능의 하부요인에서 의사소통, 충동성의 하부영역에서 운동 충동성, 스트레스의 하부요인에서 친구관련 스트레스, 일반적 특성에서 성별(남학생), 학년(중학생)으로 확인되었으며, 30.9%의 설명력을 나타내었다. 결론적으로 본 연구는 청소년의 집단따돌림 유형(가해 및 피해)에 가족기능, 충동성, 스트레스의 역할을 실증적으로 확인하였다는 점과 청소년의 집단따돌림 유형에 따른 중재방안의 기초 자료를 제공하였다는 점에서 의의를 찾을 수 있다.

Semiparametric Bayesian Regression Model for Multiple Event Time Data

  • Kim, Yongdai
    • Journal of the Korean Statistical Society
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    • 제31권4호
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    • pp.509-518
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    • 2002
  • This paper is concerned with semiparametric Bayesian analysis of the proportional intensity regression model of the Poisson process for multiple event time data. A nonparametric prior distribution is put on the baseline cumulative intensity function and a usual parametric prior distribution is given to the regression parameter. Also we allow heterogeneity among the intensity processes in different subjects by using unobserved random frailty components. Gibbs sampling approach with the Metropolis-Hastings algorithm is used to explore the posterior distributions. Finally, the results are applied to a real data set.

Least-Squares Support Vector Machine for Regression Model with Crisp Inputs-Gaussian Fuzzy Output

  • Hwang, Chang-Ha
    • Journal of the Korean Data and Information Science Society
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    • 제15권2호
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    • pp.507-513
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    • 2004
  • Least-squares support vector machine (LS-SVM) has been very successful in pattern recognition and function estimation problems for crisp data. In this paper, we propose LS-SVM approach to evaluating fuzzy regression model with multiple crisp inputs and a Gaussian fuzzy output. The proposed algorithm here is model-free method in the sense that we do not need assume the underlying model function. Experimental result is then presented which indicate the performance of this algorithm.

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부인암 여성의 성기능 예측요인 (A Study on the Predictive Factors of Sexual Function in Women with Gynecologic Cancer)

  • 박정숙;장순양
    • 종양간호연구
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    • 제12권2호
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    • pp.156-165
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    • 2012
  • Purpose: This study was to identify predictors of sexual function in gynecologic cancer patients. Methods: The participants were 154 patients treated at a university medical center in A city, Korea. The data collection was performed through a structured questionnaire from July to December, 2010. The instruments used in this study were Female Sexual Function Index (FSFI) perceived health status scale, Eastern Cooperative Oncology Group (ECOG) performance status, body image, and depression. Data were analyzed using descriptive statistics, Mann-Whitney test, Kruskal-Wallis test and stepwise multiple regression with the SPSS 18.0. Results: The mean score of perceived health status was 8.42 and sexual function was 8.42. The lowest score among sexual function was lubrication. The scores of sexual function was significantly different by age, job, marital status, period after diagnosis of cancer and diagnosis. There were significant correlations between sexual function, perceived health status, ECOG performance, body image and depression. In multiple regression analysis, predictors were identified as ECOG performance, age, diagnosis and period after diagnosis of cancer (Adj.$R^2$=.28). The most powerful predictor of female sexual function was ECOG performance (19.0%). Conclusion: The above findings indicate that it is necessary to develop a more effective and personalized sexual function improvement program for gynecologic cancer patient.

방화 발생에 영향을 미치는 요인에 관한 연구 (A Study on the Factors Affecting the Arson)

  • 김영철;박우성;이수경
    • 한국화재소방학회논문지
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    • 제28권2호
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    • pp.69-75
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    • 2014
  • 본 연구에서는 방화발생에 영향을 미치는 요인을 도출하기 위하여 발생건수를 종속변수로 하고 경제 인구 사회적 요인을 독립변수로 하는 다중회귀분석을 실시하였다. 다중회귀분석은 선형함수, 준로그함수, 역준로그함수, 이중로그함수 4가지 함수형태에 대해 적용하였으며, 각 단계별로 변수의 선택과 제외를 고려하는 단계적선택 방식을 적용하였다. 다중공선성 문제와 자기상관 문제를 해결하기 위하여 분산확대지수(VIF)와 Durbin-Watson 계수 이용하였으며, 4가지 함수모형에 대하여 수정된 R 제곱(설명력) 값이 0.935 (93.5%)로 가장 값이 높고 통계적으로 유의한 선형함수모형을 최적의 모형으로 결정하고 모형에 대한 해석을 진행하였다. 선형함수모형 결과 방화발생에 영향을 미치는 요인은 범죄발생건수(0.829), 일반이혼율(0.151), 재정자주도(0.149), 소비자물가상승률(0.099) 순으로 도출되었다.

공동주택의 건물외부조건과 에너지비용과의 관계분석 (Relation between the Building Exterior Conditions and Energy Costs in the Running period of the Apartment Housing)

  • 이강희;류승훈;이은택
    • KIEAE Journal
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    • 제9권1호
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    • pp.107-113
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    • 2009
  • The energy cost is resulted from the energy use. Its sources are divided into some types and depended on the building use or energy-use type. The energy cost should be affected by the amount of the energy use. The cost could be calculated to consider various factors such as the insulation, heating type, building shape and others. But it can not consider all of the affect factors to the energy cost and need to categorize the factors to the condition for estimating the cost. In this paper, it aimed at providing the estimation model in linear equation and multiple linear regression, utilizing the building exterior condition and management characteristics in apartment housing. Its survey are conducted in two parts of management characteristics and building exterior condition. The correlation analysis is conducted to get rid of the multicolinearity among the inputted factors. The number of linear equation model is 11 and includes the 1st, 2nd and 3rd equation function, power function and others. Among these, it suggested the 2nd and 3rd function and power function in terms of the statistics. In multiple linear regression model, the building volume and management area are inputted to the estimation.