Student's t distribution is commonly used to test if the difference between the means of two samples is
statistically significant. It is a variation of the normal distribution that takes into account that the mean of a
sample is only an estimate for the mean of the population.
The Student t distribution has one shape parameter: the degrees of freedom, commonly denoted by the Greek letter
ν. The probability density function is:
The Student t distribution is implemented by the StudentTDistribution class. It has one constructor
with the degrees of freedom as its only argument.
The following constructs the Student t distribution with 8 degrees of freedom:
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StudentTDistribution studentT = new StudentTDistribution(8);
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Dim studentT As StudentTDistribution = New StudentTDistribution(8)
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The StudentTDistribution class has one specific properties, DegreesOfFreedom, which returns the
degrees of freedom of the distribution.
StudentTDistribution has one static (Shared in Visual Basic) method, Sample(Random), which generates a
random variate using a user-supplied uniform random number generator. The second and third parameters are the
location and scale parameters of the distribution.
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MersenneTwister random = new MersenneTwister();
double variate = StudentTDistribution.GetRandomVariate(random, 8);
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Dim random As MersenneTwister = New MersenneTwister()
Dim variate As Double = StudentTDistribution.GetRandomVariate(random, 1.8)
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The above example uses the MersenneTwister class to generate uniform random numbers.
For details of the properties and methods common to all continuous distribution classes, see the topic on
class.