Difference between revisions of "Binomial distribution"
Line 2: | Line 2: | ||
[[Category:Doc Status C]] <!-- For Lumina use, do not change --> | [[Category:Doc Status C]] <!-- For Lumina use, do not change --> | ||
− | + | == 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. | |
− | = 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 | ||
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 | ||
Line 15: | Line 12: | ||
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>. | ||
− | = | + | ==Example== |
+ | An example of a binomial distribution: | ||
+ | : [[image:BinomialDistribution.png]] | ||
+ | == Library == | ||
Distributions | Distributions | ||
− | = See Also = | + | == 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) | + | * [[Poisson]](mean) |
+ | * [[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:
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
Enable comment auto-refresher
Marksmith
Lchrisman