7-11-1

Distributions

7-11 Distributions

Though there are a number of different types of distributions, the one most commonly used is the “Normal Distribution”, which is an essential type of distribution for statistical calculations. Other types of distributions include the Poisson distribution and geometric distribution. The type of distribution used depends on the type of data being handled.

The shape of a distribution makes it possible to determine trends in data somewhat. You can specify a value and calculate the probability that any data value from the distribution is, for example, less than the specifi ed value. In other words, you can determine what percent from the bottom that data value occurs within the distribution.

The following is a list of distributions and the description of what each one calculates.

 

Distribution Name

Description

Normal Distribution

 

 

 

 

 

Normal Probability Density

Calculates the normal probability density for a specified

 

 

value.

 

Normal Cumulative

Calculates the cumulative probability of a normal distribution

 

Distribution

between a lower bound and an upper bound.

 

 

 

 

Inverse Normal Cumulative

Calculates the boundary value(s) of a normal cumulative

 

Distribution

probability distribution for specified values.

 

 

 

t Distribution

 

 

Student-tProbability

Calculates the Student-tprobability density for a specified

 

Density

value.

 

 

 

 

Student-tCumulative

Calculates the cumulative probability of a Student-t

 

Distribution

distribution between a lower bound and an upper bound.

 

 

 

 

Inverse Student-t

Calculates the lower bound value of a Student-tcumulative

 

Cumulative Distribution

probability distribution for specified values.

 

 

 

χ2 Distribution

 

 

χ2 Probability Density

Calculates the χ2 probability density for a specified value.

 

χ2 Cumulative Distribution

Calculates the cumulative probability of a χ2 distribution

 

 

between a lower bound and an upper bound.

 

 

 

 

Inverse χ2 Cumulative

Calculates the lower bound value of a χ2 cumulative

 

Distribution

probability distribution for specified values.

 

 

 

F Distribution

 

 

F Probability Density

Calculates the F probability density for a specified value.

 

 

 

 

F Cumulative Distribution

Calculates the cumulative probability of an F distribution

 

 

between a lower bound and an upper bound.

 

Inverse F Cumulative

Calculates the lower bound value of an F cumulative

 

Distribution

probability distribution for specified values.

 

 

 

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