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Property Value
Hex Value $BB1D
Categories
Localizations
  • FR: Χ²Fdp(

χ²pdf(

Overview

Computes the probability density function (pdf) for the χ² distribution at a specified x value for the specified degrees of freedom df.

Availability: Token available everywhere.

Syntax

χ²pdf(x,df)

Arguments

NameTypeOptional
χ²
x
df

Location

2nd, distr, DISTR, 7:pdf(


Description

χ²pdf( is the χ² probability density function.

Since the χ² distribution is continuous, the value of χ²pdf( doesn't represent an actual probability — in fact, one of the only uses for this command is to draw a graph of the χ² curve. You could also use it for various calculus purposes, such as finding inflection points.

The command takes two arguments: the value at which to evaluate the p.d.f., and df, the number of 'degrees of freedom'.

Formulas

The value of χ²pdf( is given by

(1) \(\begin{align} \texttt{\chi^2pdf}(x,k)=\frac{(1/2)^{k/2}}{(k/2-1)!}\,x^{k/2-1}e^{-x/2} \end{align}\)


Source: parts of this page were written by the following TI|BD contributors: burr, DarkerLine, GoVegan, kg583.

History

Calculator OS Version Description
TI-83 0.01013 Added
Authors: Adrien Bertrand