As an important decision, we may consider absorbing multiple experts and not just one person's opinion. So is the problem with machine learning, which is the idea behind the meta-algorithm (META-ALGORITHM) .meta-algorithm is a way to combine other algorithms , and one of the most popular algorithms is the adaboost algorithm . Some people think that AdaBoost is the best way to supervise learning , so this method is one of the most powerful tools in the Machine learning Toolkit. The general struc
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Preface:
Decision treeAlgorithmIt has many good features, such as low training time complexity, fast prediction process, and easy model display (easy to make the decision tree into images. But at the same time, there are some bad aspects of a single decision tree
Regionlets for Generic Object DetectionThis article is a translation of this article and self-understanding, article: http://download.csdn.net/detail/autocyz/8569687Summary:For the general object detection, the problem now facing is how to solve the problem of recognition by the change of angle of object with comparatively simple calculation method. To solve this problem, it is necessary to require a flexible method of object description, and this method can be well judged for objects in differe
Copyright Notice:This article was published by Leftnoteasy on http://leftnoteasy.cnblogs.com , this article can be reproduced or partially used, but please indicate the source, if there is a problem, please contact [email protected]Objective:Decision tree This algorithm has many good characteristics, for example, the training time complexity is low, the prediction process is relatively fast, the model is easy to display (easy to get the decision tree into a picture display) and so on. But at the
regression. It does this by fitting simple models to localized subsets of the data to build up a function that describes the Determini Stic part of the variation in the data, point by point. In fact, one of the chief attractions of this method is and the data analyst is not required to specify a global function of any form to fit a model to the data, only to fit segments of the data."Using local data to fit local points by point--without global function fitting model--local problem solving"http
Advantages and disadvantages of AdaBoost (adaptive boosting,adaptive Boosting) algorithm algorithm:
advantages: Low generalization error rate, easy coding, can be used in most of the classifier, no parameter adjustment
cons: Sensitive to outliers.
Meta-algorithm (meta algorithm)
In the classification problem, we may not just want to use a classifier, we will consider the combi
/packages/elasticnet/index.html). Glmpath package can get generalized linear model and Cox model of L1 regularization path (http://cran.r-project.org/web/packages/glmpath/index.html). Penalized package Execution Lasso (L1) and Ridge (L2) penalty regression model (penalized regression models) (http://cran.r-project.org/web/packages/ penalized/index.html). The PAMR package performs a reduced centroid taxonomy (shrunken centroids classifier) (http://cran.r-project.org/web/packages/pamr/index.html).
As an important decision, you may be able to draw on more than one expert and not just a single person's opinion. Is it so when machine learning deals with problems? This is the idea behind the meta-algorithm . Meta-algorithms are a way to combine other algorithms.The bootstrap aggregation method (bootstrap aggregating), also known as the bagging method, is a technique for obtaining s new datasets after selecting S from the original data set. The new dataset and the original dataset are of equal
GBDT xgboostOutlineIntroductionGBDT Modelxgboost ModelGBDT vs. XgboostExperimentsReferencesIntroductionGradient Boosting decision Tree is a machine learning technique for regression and classification problems, which produces a predic tion model in the form of a ensemble of Basic Learning Models, typically decision
trees
.
decision Tree : e.g.eXtreme Gradient Boosting (xgboost) is an effici
learning theory, such as SVM and boosting classification methods, based on the regenerative kernel theory of non-linear data analysis and processing methods, with Lasso as the representative of the sparse learning model and application, and so on. These results should be the work of both the statistical community and the computer science community.However, machine learning has also undergone a brief period of wandering. I felt it, because at the end
such as Hangyuan Li, Xiangliang, Wang Haifeng, tie and Kaiyu have lectured at the conference. This book speaks of a lot of machine learning at the forefront of specific applications, need to have a basic ability to understand. If you want to learn about machine learning trends, you can browse the book. Academic conferences in the area of interest are the way to discover research trends.
"Managing Gigabytes" (Deep search engine) PDFA good book for information retrieval.
"Modern Information R
Preface:
The decision tree algorithm has many good features, such as low training time complexity, fast prediction process, and easy model display (easy to make the decision tree into images. But at the same time, there are some bad aspects of a single decision tree, such as over-fitting, although there are some methods, such as pruning can reduce this situation, but it is still not enough.
Model combinations (such as boosting and bagging) have many a
Xgboost Series
ubuntu14.04 Installation
Pip Install Xgboost
Error
sudo apt-get update
It turned out the same mistake.
Workaround:
sudo-h pip install--pre xgboostsuccessfully installed xgboostcleaning up ...
It worked!
Over fittingWhen you observe the training accuracy is high, but the detection accuracy is low, it is likely that you encounter over-fitting problems.
Xgboost is a good boosting model with fast effect.The
, David. The foundation of pattern recognition, but the better method of SVM and boosting method is not introduced in the recent dominant position, and is evaluated as "exhaustive suspicion".
"Pattern Recognition and machine learning" PDFAuthor Christopher M. Bishop[6], abbreviated to PRML, focuses on probabilistic models, is a Bayesian method of the tripod, according to the evaluation "with a strong engineering breath, can cooperate with Stanford U
such as Hangyuan Li, Xiangliang, Wang Haifeng, tie and Kaiyu have lectured at the conference. This book speaks of a lot of machine learning at the forefront of specific applications, need to have a basic ability to understand. If you want to learn about machine learning trends, you can browse the book. Academic conferences in the area of interest are the way to discover research trends.
"Managing Gigabytes" (Deep search engine) PDFA good book for information retrieval.
"Modern Information R
Xgboost series ubuntu14.04 installation {code...} error solution: {code...} success! Overfitting when you observe that the training accuracy is high, but the detection accuracy is low, it is very likely that you encounter an over-fitting problem. Xgboost is a high-speed boosting model... xgboost series
Ubuntu14.04 installation
pip install xgboost
Error
sudo apt-get update
Errors with the same results
Solution:
sudo -H pip install --pre xgboostSuccessf
learning textbook (machine learning-Zhou Zhihua): Boosting mainly focuses on reducing deviations, so boosting can build strong integration based on learners with fairly weak generalization performance; bagging focuses on reducing variance, so it's not pruning in decision trees , and neural networks are more effective in learning.Random forests (forest) and GBDT are all part of the Integrated Learning (Ense
it introduces.
1 score(q,d) = 2 queryNorm(q) 3 · coord(q,d) 4 · ∑ ( 5 tf(t in d) 6 · idf(t)² 7 · t.getBoost() 8 · norm(t,d) 9 ) (t in q)
The meaning of each line is as follows:
Score (q, d) is the correlation score of document d for querying q.
QueryNorm (q) is the Query Normalization Factor, which is newly added.
Coord (q, d) is a Coordination Factor, which is newly add
from Import EnsembleIntegrated classifier (Ensemble):1.bagging (Ensemble.bagging.BaggingClassifier)Set up a basic classifier for randomly selected sub-sample sets, and then vote to determine the final classification results.2.RandomForest (Ensemble. Randomforestclassifier)Set M cart (Classifier and Regression Tree) for randomly selected sub-sample sets, then vote to determine the final classification resultThe meaning of the random here:1) Random Selection sub-sample set in Bootstrap2) The rando
Bloggers have recently been fascinated by the monster hunters, the article dragged on for a long time to begin to penFirst, the algorithmAdditiveregression, a more famous name can be called GBDT (grandient boosting decision tree) gradient descent classification tree, or GBRT (Grandient boosting Regression Tree) gradient descent regression trees, is a multi-classifier combination algorithm, more specifically
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