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Predict Method for Family of Naive Bayes Objects

infix_class_prob.Rd

The infix operators %class% and %prob% are shorthands for performing classification and obtaining posterior probabilities, respectively.

Usage

lhs %class% rhs
lhs %prob% rhs

Arguments

lhs

object of class inheriting from "naive_bayes" and "*_naive_bayes" family.

rhs

dataframe or matrix for "naive_bayes" objects OR matrix for all "*_naive_bayes" objects.

Value

  • %class% returns factor with class labels corresponding to the maximal conditional posterior probabilities.

  • %prob% returns a matrix with class label specific conditional posterior probabilities.

Details

If lhs is of class inheriting from the family of the Naive Bayes objects and rhs is either dataframe or matrix then the infix operators %class% and %prob% are equivalent to:

  • lhs %class% rhs <=> predict(lhs, newdata = rhs, type = "class", threshold = 0.001, eps = 0)

  • lhs %prob% rhs <=> predict(lhs, newdata = rhs, type == "prob", threshold = 0.001, eps = 0)

Compared to predict(), both operators do not allow changing values of fine tuning parameters threshold and eps.

Author

Michal Majka, michalmajka@hotmail.com

See also

predict.naive_bayes, predict.bernoulli_naive_bayes, predict.multinomial_naive_bayes, predict.poisson_naive_bayes, predict.gaussian_naive_bayes, predict.nonparametric_naive_bayes

Examples

### Fit the model
nb <- naive_bayes(Species ~ ., iris)

newdata <- iris[1:5,-5] # Let's pretend

### Classification
nb %class% newdata
#> [1] setosa setosa setosa setosa setosa
#> Levels: setosa versicolor virginica
predict(nb, newdata, type = "class")
#> [1] setosa setosa setosa setosa setosa
#> Levels: setosa versicolor virginica

### Posterior probabilities
nb %prob% newdata
#>      setosa   versicolor    virginica
#> [1,]      1 2.981309e-18 2.152373e-25
#> [2,]      1 3.169312e-17 6.938030e-25
#> [3,]      1 2.367113e-18 7.240956e-26
#> [4,]      1 3.069606e-17 8.690636e-25
#> [5,]      1 1.017337e-18 8.885794e-26
predict(nb, newdata, type = "prob")
#>      setosa   versicolor    virginica
#> [1,]      1 2.981309e-18 2.152373e-25
#> [2,]      1 3.169312e-17 6.938030e-25
#> [3,]      1 2.367113e-18 7.240956e-26
#> [4,]      1 3.069606e-17 8.690636e-25
#> [5,]      1 1.017337e-18 8.885794e-26