• 제목/요약/키워드: regression algorithm

검색결과 1,044건 처리시간 0.095초

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
    • /
    • 제15권2호
    • /
    • pp.507-513
    • /
    • 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.

  • PDF

Quadratic Loss Support Vector Interval Regression Machine for Crisp Input-Output Data

  • Hwang, Chang-Ha
    • Journal of the Korean Data and Information Science Society
    • /
    • 제15권2호
    • /
    • pp.449-455
    • /
    • 2004
  • Support vector machine (SVM) has been very successful in pattern recognition and function estimation problems for crisp data. This paper proposes a new method to evaluate interval regression models for crisp input-output data. The proposed method is based on quadratic loss SVM, which implements quadratic programming approach giving more diverse spread coefficients than a linear programming one. The proposed algorithm here is model-free method in the sense that we do not have to assume the underlying model function. Experimental result is then presented which indicate the performance of this algorithm.

  • PDF

Algorithm for finding the best regression models using NIR spectra

  • Cho, Jung-Hwan;Huh, Yun-Jung;Park, Young-Joo
    • 대한약학회:학술대회논문집
    • /
    • 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
    • /
    • pp.402.2-402.2
    • /
    • 2002
  • An algorithm for finding the best regression models has been developed using NIR spectral data. In cases of regression analysis for quantitation with NIR spectral data, it is very critical to find essential features from the spectral data. This task was accessed in two ways. The first one was to use all-possible combinations of varibles (wavelengths). Correlation coefficients at each spectral points were calculated to get initial set of variables and all of the possible combinations of variable sets were tested with SEC. SEP and/or $R^2$. (omitted)

  • PDF

결측 공변량을 갖는 혼합회귀모형에서의 EM 알고리즘 (The EM algorithm for mixture regression with missing covariates)

  • 김형민;함건희;서병태
    • 응용통계연구
    • /
    • 제29권7호
    • /
    • pp.1347-1359
    • /
    • 2016
  • 혼합회귀모형은 반응 변수와 공변량 사이의 관계를 규명하는 유용한 통계적 모형으로 여러 분야에서 사용되어지고 있다. 하지만 실제로 혼합회귀모형을 이용하여 분석을 하는 과정에서 공변량이 결측값을 포함하는 문제는 흔하게 발생하며, 발생하는 결측의 유형 또한 다양하게 나타난다. 이러한 경우에 있어서 본 논문에서는 최대우도추정량을 구하기 위한 EM 알고리즘을 제안하고자 한다. 제안된 EM 알고리즘의 효용성을 모의실험을 통해 확인하였으며 또한 사례연구를 통해 제시된 방법이 어떻게 사용될수 있는지와 그 효용성을 함께 확인하였다.

A New Forest Fire Detection Algorithm using Outlier Detection Method on Regression Analysis between Surface temperature and NDVI

  • Huh, Yong;Byun, Young-Gi;Son, Jeong-Hoon;Yu, Ki-Yun;Kim, Yong-Il
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
    • /
    • pp.574-577
    • /
    • 2006
  • In this paper, we developed a forest fire detection algorithm which uses a regression function between NDVI and land surface temperature. Previous detection algorithms use the land surface temperature as a main factor to discriminate fire pixels from non-fire pixels. These algorithms assume that the surface temperatures of non-fire pixels are intrinsically analogous and obey Gaussian normal distribution, regardless of land surface types and conditions. And the temperature thresholds for detecting fire pixels are derived from the statistical distribution of non-fire pixels’ temperature using heuristic methods. This assumption makes the temperature distribution of non-fire pixels very diverse and sometimes slightly overlapped with that of fire pixel. So, sometimes there occur omission errors in the cases of small fires. To ease such problem somewhat, we separated non-fire pixels into each land cover type by clustering algorithm and calculated the residuals between the temperature of a pixel under examination whether fire pixel or not and estimated temperature of the pixel using the linear regression between surface temperature and NDVI. As a result, this algorithm could modify the temperature threshold considering land types and conditions and showed improved detection accuracy.

  • PDF

GA-optimized Support Vector Regression for an Improved Emotional State Estimation Model

  • Ahn, Hyunchul;Kim, Seongjin;Kim, Jae Kyeong
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제8권6호
    • /
    • pp.2056-2069
    • /
    • 2014
  • In order to implement interactive and personalized Web services properly, it is necessary to understand the tangible and intangible responses of the users and to recognize their emotional states. Recently, some studies have attempted to build emotional state estimation models based on facial expressions. Most of these studies have applied multiple regression analysis (MRA), artificial neural network (ANN), and support vector regression (SVR) as the prediction algorithm, but the prediction accuracies have been relatively low. In order to improve the prediction performance of the emotion prediction model, we propose a novel SVR model that is optimized using a genetic algorithm (GA). Our proposed algorithm-GASVR-is designed to optimize the kernel parameters and the feature subsets of SVRs in order to predict the levels of two aspects-valence and arousal-of the emotions of the users. In order to validate the usefulness of GASVR, we collected a real-world data set of facial responses and emotional states via a survey. We applied GASVR and other algorithms including MRA, ANN, and conventional SVR to the data set. Finally, we found that GASVR outperformed all of the comparative algorithms in the prediction of the valence and arousal levels.

유전자 알고리즘을 이용한 신경망 설계 (Designing Neural Network Using Genetic Algorithm)

  • 박정선
    • 한국정보처리학회논문지
    • /
    • 제4권9호
    • /
    • pp.2309-2314
    • /
    • 1997
  • 본 연구는 보험 회사의 파산 예측을 위하여 신경회로망이 사용되는데 이를 최적화하기 위하여 유전자 알고리즘이 사용된다. 유전자 알고리즘은 최적의 네트워크 구조와 매개변수들을 제시해 준다. 유전자 알고리즘에 의해 설계된 신경회로망은 파산 예측을 함에 있어 discriminant analysis, logistic regression, ID3, CART 등과 비교되는데 가장 좋은 성능을 보여준다.

  • PDF

Constrained $L_1$-Estimation in Linear Regression

  • Kim, Bu-Yong
    • Communications for Statistical Applications and Methods
    • /
    • 제5권3호
    • /
    • pp.581-589
    • /
    • 1998
  • An algorithm is proposed for the $L_1$-estimation with linear equality and inequality constraints in linear regression model. The algorithm employs a linear scaling transformation to obtain the optimal solution of linear programming type problem. And a special scheme is used to maintain the feasibility of the updated solution at each iteration. The convergence of the proposed algorithm is proved. In addition, the updating and orthogonal decomposition techniques are employed to improve the computational efficiency and numerical stability.

  • PDF

머신러닝 알고리즘 기반의 의료비 예측 모델 개발 (Development of Medical Cost Prediction Model Based on the Machine Learning Algorithm)

  • Han Bi KIM;Dong Hoon HAN
    • Journal of Korea Artificial Intelligence Association
    • /
    • 제1권1호
    • /
    • pp.11-16
    • /
    • 2023
  • Accurate hospital case modeling and prediction are crucial for efficient healthcare. In this study, we demonstrate the implementation of regression analysis methods in machine learning systems utilizing mathematical statics and machine learning techniques. The developed machine learning model includes Bayesian linear, artificial neural network, decision tree, decision forest, and linear regression analysis models. Through the application of these algorithms, corresponding regression models were constructed and analyzed. The results suggest the potential of leveraging machine learning systems for medical research. The experiment aimed to create an Azure Machine Learning Studio tool for the speedy evaluation of multiple regression models. The tool faciliates the comparision of 5 types of regression models in a unified experiment and presents assessment results with performance metrics. Evaluation of regression machine learning models highlighted the advantages of boosted decision tree regression, and decision forest regression in hospital case prediction. These findings could lay the groundwork for the deliberate development of new directions in medical data processing and decision making. Furthermore, potential avenues for future research may include exploring methods such as clustering, classification, and anomaly detection in healthcare systems.

Fuzzy c-Regression Using Weighted LS-SVM

  • Hwang, Chang-Ha
    • 한국데이터정보과학회:학술대회논문집
    • /
    • 한국데이터정보과학회 2005년도 추계학술대회
    • /
    • pp.161-169
    • /
    • 2005
  • In this paper we propose a fuzzy c-regression model based on weighted least squares support vector machine(LS-SVM), which can be used to detect outliers in the switching regression model while preserving simultaneous yielding the estimates of outputs together with a fuzzy c-partitions of data. It can be applied to the nonlinear regression which does not have an explicit form of the regression function. We illustrate the new algorithm with examples which indicate how it can be used to detect outliers and fit the mixed data to the nonlinear regression models.

  • PDF