Difference between revisions of "Beta distributions"
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Lets generate a beta distribution using the ''rbeta'' built in R function. | Lets generate a beta distribution using the ''rbeta'' built in R function. | ||
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# Alter the parameters | # Alter the parameters | ||
n <- 1000 # Number of observations | n <- 1000 # Number of observations |
Revision as of 03:24, 2 August 2006
Beta distributions
For details on the beta distribution see WikiPedia:Beta distribution. Notice that thee distribution is symmetric for the parameters p, and q (α & β in the Wikipedia article formula), and that the x axis range is from 0 to 1, a probability.
R programming language
For help on functions which create/manipulate beta distributions see;
?beta # or help(beta) ?rbeta # or help(rbeta) |
Usage examples are provided at;
example(beta) example(rbeta) example(dbeta) example(pbeta) example(qbeta) |
Lets generate a beta distribution using the rbeta built in R function.
quartz() # Alter the parameters n <- 1000 # Number of observations p <- 0.1 q <- 0.1 x <- rbeta(n, shape1= p, shape2=q) breaks <- seq(0,1, length=21) hist(x, breaks=breaks, freq=FALSE) lines(density(x, adjust=0.4), col="red") |