Student's t-Distribution

Functions > Statistics > Probability Distributions > Student's t-Distribution

Student's t-Distribution

The following functions are associated with the Student's t-distribution equation:

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• dt(x, d)—Returns the probability density for value x.

• pt(x, d)—Returns the cumulative probability distribution for value x.

• qt(p, d)—Returns the inverse cumulative probability distribution for probability p.

• rt(m, d)—Returns a vector of m random numbers having the Student's t-distribution.

Arguments

• x is a scalar or vector of real values.

• d is a positive integer representing the degrees of freedom. While the distribution equation is meant to be formulated for integers, you can also use real values.

• p is a real probability, 0 ≤ p ≤ 1.

• m is an integer, m > 0.

• All arguments are unitless numbers.

In previous versions of PTC Mathcad Prime, units were allowed in the arguments of the random numbers distribution function. Starting with PTC Mathcad Prime 10.0.0.0, all arguments are unitless. This change was made to align the behavior of the random distribution function to other probability distribution functions. If your arguments used units, make sure to adjust them for maintaining a correct scaling.

Related Topics

About Probability Distribution Functions

Example: T-Test on Normal Means

Example: T-Score of a Vector of Data

Example: Confidence Interval for the Mean

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