Difference between revisions of "Binomial distribution"

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[[Category:Doc Status C]] <!-- For Lumina use, do not change -->
 
[[Category:Doc Status C]] <!-- For Lumina use, do not change -->
  
[[image:BinomialDistribution.png]]
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== Binomial(n, p) ==
 
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Consider an event—such as a coin coming down heads—that can be true or false in each trial—or each toss—with probability «p» -- it has a [[Bernoulli]] distribution. A binomial distribution describes the number of times an event is true -- e.g., the coin is heads -- in «n» independent trials—or tosses—where the event occurs with probability «p» on each trial.
= Binomial( n,p ) =
 
 
 
Consider an event—such as a coin coming down heads—that can be true or false in each trial—or each toss—with probability ''p'' -- it has a Bernoulli distribution. A binomial distribution describes the number of times an event is true -- e.g., the coin is heads -- in ''n'' independent trials—or tosses—where the event occurs with probability p on each trial.
 
  
 
The Binomial distribution is a non-negative discrete distribution where the probability of outcome ''k'' is given by  
 
The Binomial distribution is a non-negative discrete distribution where the probability of outcome ''k'' is given by  
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The distribution has a [[Mean]] of <code>n*p</code> and a [[Variance]] of <code>n*p*(1-p)</code>.
 
The distribution has a [[Mean]] of <code>n*p</code> and a [[Variance]] of <code>n*p*(1-p)</code>.
  
= Library =
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==Example==
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An example of a binomial distribution:
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: [[image:BinomialDistribution.png]]
  
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== Library ==
 
Distributions
 
Distributions
  
= See Also =
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== See Also ==
 
 
 
* [[CumBinomial]] -- the analytica cumulative probability function for Binomial
 
* [[CumBinomial]] -- the analytica cumulative probability function for Binomial
 
* [[Prob_Binomial]] -- the analytic probability function for Binomial
 
* [[Prob_Binomial]] -- the analytic probability function for Binomial
 
* [[CumBinomialInv]] -- the analytica inverse cumulative probability function for Binomial
 
* [[CumBinomialInv]] -- the analytica inverse cumulative probability function for Binomial
 
* [[Multinomial]] -- A generalization of Binomial in which more than two outcomes are possible.
 
* [[Multinomial]] -- A generalization of Binomial in which more than two outcomes are possible.
* [[Poisson]](mean), [[NegativeBinomial]](r,p) -- the two other common discrete distributions on the non-negative integers
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* [[Poisson]](mean)
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* [[NegativeBinomial]] -- the two other common discrete distributions on the non-negative integers

Revision as of 00:37, 16 January 2016


Binomial(n, p)

Consider an event—such as a coin coming down heads—that can be true or false in each trial—or each toss—with probability «p» -- it has a Bernoulli distribution. A binomial distribution describes the number of times an event is true -- e.g., the coin is heads -- in «n» independent trials—or tosses—where the event occurs with probability «p» on each trial.

The Binomial distribution is a non-negative discrete distribution where the probability of outcome k is given by

[math]\displaystyle{ P_{n,p}(k) = \left(\begin{array}{c}n\\k\end{array}\right) p^k (1-p)^{n-k} }[/math]

This analytic probability is computed by the library function Prob_Binomial, and the cumulative probability by CumBinomial.

The distribution has a Mean of n*p and a Variance of n*p*(1-p).

Example

An example of a binomial distribution:

BinomialDistribution.png

Library

Distributions

See Also

  • CumBinomial -- the analytica cumulative probability function for Binomial
  • Prob_Binomial -- the analytic probability function for Binomial
  • CumBinomialInv -- the analytica inverse cumulative probability function for Binomial
  • Multinomial -- A generalization of Binomial in which more than two outcomes are possible.
  • Poisson(mean)
  • NegativeBinomial -- the two other common discrete distributions on the non-negative integers
Comments


Marksmith

102 months ago
Score 0
It would still be useful to have a built-in function, say Binomial(n,p,k1,k2) that samples from the conditional Binomial distribution X|k1<=X<=k2. UDFs for the conditional Poisson are easier to write and operate quicker than for the conditional Binomial.

Lchrisman

79 months ago
Score 0
Mark -- Try: Truncate( Binomial(n, p), k1, k2 )

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