Naive Bayes (Naive) explain the meaning of

"Naive" Origin

Naive Bayes (Naive Bayes) is a group of supervised learning algorithm, which is based on Bayes' theorem, "naively" "naive" is assumed independent of each other between the features, i.e., the presence of a characteristic independent of the presence of other features. This is the "simple" reason the word "Naive".
Bayes's law and case: https://blog.csdn.net/houhuipeng/article/details/90706539

sample E = ( x 1 , x 2 . . . x n ) E=(x_1,x_2...x_n) Belong to the category c c probability:
p ( c E ) = p ( E c ) p ( c ) p E p(c|E)=\frac{p(E|c)p(c)}{p{E}} When satisfied E E is c c 's Probability greater than Example - When the embodiment, may be determined E E belong c c
f b ( E ) = p ( C = + E ) p = E 1 f_b(E)=\frac {p(C=+|E)}{p=-|E} \geq1 is assumed mutually independent features, then p ( E c ) = p ( x 1 , x 2 . . . x n c ) = i = 1 n p ( x i c ) p(E|c)=p(x_1,x_2...x_n|c)=\prod_{i=1}^np(x_i|c)
finally available: f n b ( E ) = p ( C = + ) p ( C = ) i = 1 n p ( x i C = + ) p ( x i C = ) f_{nb}(E)=\frac{p(C=+)}{p(C=-)}\prod_{i=1}^n\frac{p(x_i|C=+)}{p(x_i|C=-)}

Advantages and disadvantages

Naive Bayes model is a set of extremely quick and simple classification algorithm, usually for very high-dimensional data sets. Because they are so fast and tunable small, so they end up as a very useful basis for rapid classification problems.
Advantages: speed operation, less simple model tunable parameters.
Cons: assumption is not true in most cases.
Depending on the assumptions feature distribution can be divided into:

  • Naive Bayesian Gaussian
  • Naive Bayes polynomial
  • Supplementary Naive Bayes
  • Bernoulli Naive Bayes

Participate sklearn official document:
https://scikit-learn.org/stable/modules/naive_bayes.html

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Origin blog.csdn.net/houhuipeng/article/details/91363091