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Discrete Probability Distributions

NoisyOr(s, leak, c1, p1, cn, pn)

Description: This function represents a noisy Or in which the effect of the parents (the causes ci) on the symptom s can be inhibited. pi represents the probability that the cause i acts on the symptom (the inhibition probability is then 1-pi). It is also possible to define a leak probability for the set of causes that are not directly modeled.

  • Number of Parameters: even, and >= 4
  • Parameter Type: boolean, numerical, boolean, numerical, ..., boolean, numerical
  • Result Type: real
Example

The conditional probability table below corresponds to NoisyOr(?N3?, 0.1, ?N1?, 0.8, ?N2?, 0.6):

N1N2N3 = FalseN3 = True
FalseFalse(1-0.1)0.1
FalseTrue(1-0.1) * (1-0.6)0.64
TrueFalse(1-0.1) * (1-0.8)0.82
TrueTrue(1-0.1) _ (1-0.8) _ (1-0.6)0.928

NoisyAnd(s, leak, c1, p1, cn, pn)

Description: This function represents a noisy And, i.e., the Noisy Or negation.

  • Number of Parameters: even, and >= 4
  • Parameter Type: boolean, numerical, boolean, numerical, ..., boolean, numerical
  • Result Type: real
Example

The conditional probability table below corresponds to NoisyAnd(?N3?, 0.1, ?N1?, 0.8, ?N2?, 0.6):

N1N2N3 = FalseN3 = True
FalseFalse0.928(1-0.1) _ (1-0.6) _ (1-0.8)
FalseTrue0.82(1-0.1) * (1-0.8)
TrueFalse0.64(1-0.1) * (1-0.6)
TrueTrue0.1(1-0.1)

Binomial(k, n, p)

Description: Probability of obtaining exactly k occurrences of the same event of probability p among n independent experiments.

  • Number of Parameters: 3
  • Parameter Type: integer, integer, numerical
  • Result Type: real
Example

The probability distribution below corresponds to Binomial(?N1?, 20, 0.3):

2556101

NegBinomial(k, n, p)

Description: Probability of requiring k trials to have n successes of the same event of probability p among independent experiments.

  • Number of Parameters: 3
  • Parameter Type: integer, integer, numerical
  • Result Type: real
Example

The probability distribution below corresponds to NegBinomial(?N1?, 4, 0.3):

2556102

Geometric(k, p)

Description: Probability of requiring k independent experiments to obtain a first observation of an event of probability p.

  • Number of Parameters: 2
  • Parameter Type: integer, numerical
  • Result Type: real
Example

The probability distribution below corresponds to Geometric(?N1?, 0.3):

2556103

Hypergeometric(k, n, m, N)

Description: Probability of obtaining k winning objects when choosing n objects among N, where m are winning objects.

  • Number of Parameters: 4
  • Parameter Type: integer, integer, integer, integer
  • Result Type: real
Example

The probability distribution below corresponds to Hypergeometric(?N1?, 5, 5, 20):

2556104

Poisson(k, l)

Description: Probability of obtaining k observations of an event in a large number of independent experiments when the mean is l.

  • Number of Parameters: 2
  • Parameter Type: integer, real
  • Result Type: real
Example

The probability distribution below corresponds to Poisson(?N1?, 18.5):

2556105

DiscUniform(k, a, b)

Description: Uniform distribution defined by the discrete interval [a, b].

  • Number of Parameters: 3
  • Parameter Type: integer, integer, integer
  • Result Type: real

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