`nltk.KneserNeyProbDist`¶

class nltk.KneserNeyProbDist(freqdist, bins=None, discount=0.75)[source]¶: Kneser-Ney estimate of a probability distribution. This is a version of back-off that counts how likely an n-gram is provided the n-1-gram had been seen in training. Extends the ProbDistI interface, requires a trigram FreqDist instance to train on. Optionally, a different from default discount value can be specified. The default discount is set to 0.75.

Methods¶

__init__(freqdist[, bins, discount])

param freqdist:	The trigram frequency distribution upon which to base

discount() Return the value by which counts are discounted.

generate() Return a randomly selected sample from this probability distribution.

logprob(sample) Return the base 2 logarithm of the probability for a given sample.

max()

prob(trigram)

samples()

set_discount(discount) Set the value by which counts are discounted to the value of discount.

unicode_repr() Return a string representation of this ProbDist