• Title/Summary/Keyword: Regression trees

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Comparison of tree-based ensemble models for regression

  • Park, Sangho;Kim, Chanmin
    • Communications for Statistical Applications and Methods
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    • v.29 no.5
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    • pp.561-589
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    • 2022
  • When multiple classifications and regression trees are combined, tree-based ensemble models, such as random forest (RF) and Bayesian additive regression trees (BART), are produced. We compare the model structures and performances of various ensemble models for regression settings in this study. RF learns bootstrapped samples and selects a splitting variable from predictors gathered at each node. The BART model is specified as the sum of trees and is calculated using the Bayesian backfitting algorithm. Throughout the extensive simulation studies, the strengths and drawbacks of the two methods in the presence of missing data, high-dimensional data, or highly correlated data are investigated. In the presence of missing data, BART performs well in general, whereas RF provides adequate coverage. The BART outperforms in high dimensional, highly correlated data. However, in all of the scenarios considered, the RF has a shorter computation time. The performance of the two methods is also compared using two real data sets that represent the aforementioned situations, and the same conclusion is reached.

Regression Neural Networks for Improving the Learning Performance of Single Feature Split Regression Trees (단일특징 분할 회귀트리의 학습성능 개선을 위한 회귀신경망)

  • Lim, Sook;Kim, Sung-Chun
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.33B no.1
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    • pp.187-194
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    • 1996
  • In this paper, we propose regression neural networks based on regression trees. We map regression trees into three layered feedforward networks. We put multi feature split functions in the first layer so that the networks have a better chance to get optimal partitions of input space. We suggest two supervised learning algorithms for the network training and test both in single feature split and multifeature split functions. In experiments, the proposed regression neural networks is proved to have the better learning performance than those of the single feature split regression trees and the single feature split regression networks. Furthermore, we shows that the proposed learning schemes have an effect to prune an over-grown tree without degrading the learning performance.

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A review of tree-based Bayesian methods

  • Linero, Antonio R.
    • Communications for Statistical Applications and Methods
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    • v.24 no.6
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    • pp.543-559
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    • 2017
  • Tree-based regression and classification ensembles form a standard part of the data-science toolkit. Many commonly used methods take an algorithmic view, proposing greedy methods for constructing decision trees; examples include the classification and regression trees algorithm, boosted decision trees, and random forests. Recent history has seen a surge of interest in Bayesian techniques for constructing decision tree ensembles, with these methods frequently outperforming their algorithmic counterparts. The goal of this article is to survey the landscape surrounding Bayesian decision tree methods, and to discuss recent modeling and computational developments. We provide connections between Bayesian tree-based methods and existing machine learning techniques, and outline several recent theoretical developments establishing frequentist consistency and rates of convergence for the posterior distribution. The methodology we present is applicable for a wide variety of statistical tasks including regression, classification, modeling of count data, and many others. We illustrate the methodology on both simulated and real datasets.

Integrity Assessment for Reinforced Concrete Structures Using Fuzzy Decision Making (퍼지의사결정을 이용한 RC구조물의 건전성평가)

  • 박철수;손용우;이증빈
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2002.04a
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    • pp.274-283
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    • 2002
  • This paper presents an efficient models for reinforeced concrete structures using CART-ANFIS(classification and regression tree-adaptive neuro fuzzy inference system). a fuzzy decision tree parttitions the input space of a data set into mutually exclusive regions, each of which is assigned a label, a value, or an action to characterize its data points. Fuzzy decision trees used for classification problems are often called fuzzy classification trees, and each terminal node contains a label that indicates the predicted class of a given feature vector. In the same vein, decision trees used for regression problems are often called fuzzy regression trees, and the terminal node labels may be constants or equations that specify the Predicted output value of a given input vector. Note that CART can select relevant inputs and do tree partitioning of the input space, while ANFIS refines the regression and makes it everywhere continuous and smooth. Thus it can be seen that CART and ANFIS are complementary and their combination constitutes a solid approach to fuzzy modeling.

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A Combined Multiple Regression Trees Predictor for Screening Large Chemical Databases (대용량 화학 데이터 베이스를 선별하기위한 결합다중회귀나무 예측치)

  • 임용빈;이소영;정종희
    • The Korean Journal of Applied Statistics
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    • v.14 no.1
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    • pp.91-101
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    • 2001
  • It has been shown that the multiple trees predictors are more accurate in reducing test set error than a single tree predictor. There are two ways of generating multiple trees. One is to generate modified training sets by resampling the original training set, and then construct trees. It is known that arcing algorithm is efficient. The other is to perturb randomly the working split at each node from a list of best splits, which is expected to generate reasonably good trees for the original training set. We propose a new combined multiple regression trees predictor which uses the latter multiple regression tree predictor as a predictor based on a modified training set at each stage of arcing. The efficiency of those prediction methods are compared by applying to high throughput screening of chemical compounds for biological effects.

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Note on classification and regression tree analysis (분류와 회귀나무분석에 관한 소고)

  • 임용빈;오만숙
    • Journal of Korean Society for Quality Management
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    • v.30 no.1
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    • pp.152-161
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    • 2002
  • The analysis of large data sets with hundreds of thousands observations and thousands of independent variables is a formidable computational task. A less parametric method, capable of identifying important independent variables and their interactions, is a tree structured approach to regression and classification. It gives a graphical and often illuminating way of looking at data in classification and regression problems. In this paper, we have reviewed and summarized tile methodology used to construct a tree, multiple trees and the sequential strategy for identifying active compounds in large chemical databases.

An Ensemble Cascading Extremely Randomized Trees Framework for Short-Term Traffic Flow Prediction

  • Zhang, Fan;Bai, Jing;Li, Xiaoyu;Pei, Changxing;Havyarimana, Vincent
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.4
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    • pp.1975-1988
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    • 2019
  • Short-term traffic flow prediction plays an important role in intelligent transportation systems (ITS) in areas such as transportation management, traffic control and guidance. For short-term traffic flow regression predictions, the main challenge stems from the non-stationary property of traffic flow data. In this paper, we design an ensemble cascading prediction framework based on extremely randomized trees (extra-trees) using a boosting technique called EET to predict the short-term traffic flow under non-stationary environments. Extra-trees is a tree-based ensemble method. It essentially consists of strongly randomizing both the attribute and cut-point choices while splitting a tree node. This mechanism reduces the variance of the model and is, therefore, more suitable for traffic flow regression prediction in non-stationary environments. Moreover, the extra-trees algorithm uses boosting ensemble technique averaging to improve the predictive accuracy and control overfitting. To the best of our knowledge, this is the first time that extra-trees have been used as fundamental building blocks in boosting committee machines. The proposed approach involves predicting 5 min in advance using real-time traffic flow data in the context of inherently considering temporal and spatial correlations. Experiments demonstrate that the proposed method achieves higher accuracy and lower variance and computational complexity when compared to the existing methods.

Natural Spread Pattern of Damaged Area by Pine Wilt Disease Using Geostatistical Analysis (공간통계학적 방법에 의한 소나무 재선충 피해의 자연적 확산유형분석)

  • Son, Min-Ho;Lee, Woo-Kyun;Lee, Seung-Ho;Cho, Hyun-Kook;Lee, Jun-Hak
    • Journal of Korean Society of Forest Science
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    • v.95 no.3
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    • pp.240-249
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    • 2006
  • Recently, dispersion of damaged forest by pine wilt disease has been regarded as a serious social issue. Damages by pine wilt disease have been spreaded by natural area expansion of the vectors in the damaged area, while the national wide damage spread has induced by human-involved carrying infected trees out of damaged area. In this study, damaged trees were detected and located on the digital map by aerial photograph and terrestrial surveys. The spatial distribution pattern of damaged trees, and the relationship of spatial distribution of damaged trees and some geomorphological factors were geostatistically analysed. Finally, we maked natural spread pattern map of pine wilt disease using geostatistical CART(Classification and Regression Trees) model. This study verified that geostatistical analysis and CART model are useful tools for understanding spatial distribution and natural spread pattern of pine wilt diseases.

Evaluations of predicted models fitted for data mining - comparisons of classification accuracy and training time for 4 algorithms (데이터마이닝기법상에서 적합된 예측모형의 평가 -4개분류예측모형의 오분류율 및 훈련시간 비교평가 중심으로)

  • Lee, Sang-Bock
    • Journal of the Korean Data and Information Science Society
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    • v.12 no.2
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    • pp.113-124
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    • 2001
  • CHAID, logistic regression, bagging trees, and bagging trees are compared on SAS artificial data set as HMEQ in terms of classification accuracy and training time. In error rates, bagging trees is at the top, although its run time is slower than those of others. The run time of logistic regression is best among given models, but there is no uniformly efficient model satisfied in both criteria.

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Data-mining modeling for the prediction of wear on forming-taps in the threading of steel components

  • Bustillo, Andres;Lopez de Lacalle, Luis N.;Fernandez-Valdivielso, Asier;Santos, Pedro
    • Journal of Computational Design and Engineering
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    • v.3 no.4
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    • pp.337-348
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    • 2016
  • An experimental approach is presented for the measurement of wear that is common in the threading of cold-forged steel. In this work, the first objective is to measure wear on various types of roll taps manufactured to tapping holes in microalloyed HR45 steel. Different geometries and levels of wear are tested and measured. Taking their geometry as the critical factor, the types of forming tap with the least wear and the best performance are identified. Abrasive wear was observed on the forming lobes. A higher number of lobes in the chamber zone and around the nominal diameter meant a more uniform load distribution and a more gradual forming process. A second objective is to identify the most accurate data-mining technique for the prediction of form-tap wear. Different data-mining techniques are tested to select the most accurate one: from standard versions such as Multilayer Perceptrons, Support Vector Machines and Regression Trees to the most recent ones such as Rotation Forest ensembles and Iterated Bagging ensembles. The best results were obtained with ensembles of Rotation Forest with unpruned Regression Trees as base regressors that reduced the RMS error of the best-tested baseline technique for the lower length output by 33%, and Additive Regression with unpruned M5P as base regressors that reduced the RMS errors of the linear fit for the upper and total lengths by 25% and 39%, respectively. However, the lower length was statistically more difficult to model in Additive Regression than in Rotation Forest. Rotation Forest with unpruned Regression Trees as base regressors therefore appeared to be the most suitable regressor for the modeling of this industrial problem.