K-nearest neighbors algorithm

K-nearest neighbors algorithm

In statistics, the k-nearest neighbors algorithm (k-NN) is a non-parametric supervised learning method first developed by Evelyn Fix and Joseph Hodges in 1951, and later expanded by Thomas Cover. It is used for classification and regression. In both cases, the input consists of the k closest training examples in a data set. The output depends on whether k-NN is used for classification or regression: A peculiarity of the k-NN algorithm is that it is sensitive to the local structure of the data.

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enIn statistics, the k-nearest neighbors algorithm (k-NN) is a non-parametric supervised learning method first developed by Evelyn Fix and Joseph Hodges in 1951, and later expanded by Thomas Cover. It is used for classification and regression. In both cases, the input consists of the k closest training examples in a data set. The output depends on whether k-NN is used for classification or regression: A peculiarity of the k-NN algorithm is that it is sensitive to the local structure of the data.
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K-means clustering
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enIn statistics, the k-nearest neighbors algorithm (k-NN) is a non-parametric supervised learning method first developed by Evelyn Fix and Joseph Hodges in 1951, and later expanded by Thomas Cover. It is used for classification and regression. In both cases, the input consists of the k closest training examples in a data set. The output depends on whether k-NN is used for classification or regression: * In k-NN classification, the output is a class membership. An object is classified by a plurality vote of its neighbors, with the object being assigned to the class most common among its k nearest neighbors (k is a positive integer, typically small). If k = 1, then the object is simply assigned to the class of that single nearest neighbor. * In k-NN regression, the output is the property value for the object. This value is the average of the values of k nearest neighbors. k-NN is a type of classification where the function is only approximated locally and all computation is deferred until function evaluation. Since this algorithm relies on distance for classification, if the features represent different physical units or come in vastly different scales then normalizing the training data can improve its accuracy dramatically. Both for classification and regression, a useful technique can be to assign weights to the contributions of the neighbors, so that the nearer neighbors contribute more to the average than the more distant ones. For example, a common weighting scheme consists in giving each neighbor a weight of 1/d, where d is the distance to the neighbor. The neighbors are taken from a set of objects for which the class (for k-NN classification) or the object property value (for k-NN regression) is known. This can be thought of as the training set for the algorithm, though no explicit training step is required. A peculiarity of the k-NN algorithm is that it is sensitive to the local structure of the data.
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Anomaly detection
Bayes classifier
Bayes error rate
Bootstrap aggregating
Canonical correlation
Category:Classification algorithms
Category:Machine learning algorithms
Category:Nonparametric statistics
Category:Search algorithms
Category:Statistical classification
Classification
Closest pair of points problem
Computer vision
Confusion matrix
Consistency (statistics)
Continuous variable
Curse of dimensionality
Curse of Dimensionality
Data reduction
Data set
Decision boundary
Dimension reduction
Embedding
Euclidean distance
Evelyn Fix
Evolutionary algorithm
Facial recognition system
Feature (machine learning)
Feature extraction
Feature scaling
Feature selection
Feature space
Feature vector
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Haar wavelet
Hamming distance
Heuristic (computer science)
Hyperparameter optimization
Integer
Joseph Lawson Hodges Jr.
Kernel (statistics)
Large margin nearest neighbor
Large Margin Nearest Neighbor
Likelihood-ratio test
Linear discriminant analysis
Locality Sensitive Hashing
Local outlier factor
Mahalanobis distance
Mean-shift
Metric (mathematics)
Minimax
MIT Press
Mutual information
Nearest centroid classifier
Nearest neighbor search
Neighbourhood components analysis
Non-parametric statistics
Normalization (statistics)
OpenCV
Peter E. Hart
Principal Component Analysis
Pseudometric space
Regression analysis
RMSE
Self-organizing map
Statistical classification
Statistics
Supervised learning
Thomas M. Cover
Time series
Variable kernel density estimation
VLDB conference
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Algoritme k tetangga terdekat
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Giải thuật k hàng xóm gần nhất
K auzokide hurbilenak
K-nærmeste naboer
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K-nearest neighbors
K-nearest neighbors algorithm
Knn
K-NN
K vecinos más próximos
K近傍法
K-近邻算法
K-최근접 이웃 알고리즘
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Méthode des k plus proches voisins
Nächste-Nachbarn-Klassifikation
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Алгоритам к најближих суседа
Метод k-ближайших соседей
Метод k-найближчих сусідів
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الگوریتم کی-نزدیک‌ترین همسایه
كي أقرب جار
کەی نزیکترین ھاوسێکان
ขั้นตอนวิธีการค้นหาเพื่อนบ้านใกล้สุด k ตัว
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Category:Classification algorithms
Category:Machine learning algorithms
Category:Nonparametric statistics
Category:Search algorithms
Category:Statistical classification
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