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GammaDistribution

GammaDistribution[Alpha, Beta]
represents a gamma distribution with shape parameter Alpha and scale parameter Beta.
  • The probability density for value x in a gamma distribution is proportional to ⅇ^(-x/beta)x^(alpha-1) for x>0, and is zero for x<0. »
The mean and variance of a gamma distribution:
The probability density function of the gamma distribution depends on the Gamma function:
The mean and variance of a gamma distribution:
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The probability density function of the gamma distribution depends on the Gamma function:
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Generate a set of pseudorandom numbers that are gamma distributed:
Properties based on higher-order moments:
Third moment of a gamma distribution:
The 0.75 quantile of a gamma distribution with alpha=2 and beta=5:
Plot the cumulative distribution function of the random variable:
A contour plot as both x and Alpha are varied:
The probability density function integrates to unity:
Moments can be obtained from the characteristic function:
GammaDistribution and InverseGammaDistribution have an inverse relationship:
GammaDistribution is not defined when either Alpha or Beta is not a positive real number:
Substitution of invalid parameters into symbolic outputs gives results that are not meaningful:
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