CoxIngersollRossProcess
✖
CoxIngersollRossProcess
represents a Cox–Ingersoll–Ross process with long‐term mean μ, volatility σ, speed of adjustment θ, and initial condition x0.
Details

- CoxIngersollRossProcess is also known as the CIR process.
- CoxIngersollRossProcess is a continuous‐time and continuous‐state random process.
- The state
of the Cox–Ingersoll–Ross process satisfies an Ito differential equation
, where
follows a standard WienerProcess[].
- CoxIngersollRossProcess allows x0 to be any positive real number, σ to be any nonzero real number, and θ and μ to be any nonzero real numbers of the same sign.
- CoxIngersollRossProcess can be used with such functions as Mean, PDF, Probability, and RandomFunction.
Examples
open allclose allBasic Examples (3)Summary of the most common use cases
Simulate a Cox–Ingersoll–Ross process:

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-tzhca0


https://wolfram.com/xid/0is5kqbx5kczzusum14y6-b4adct


https://wolfram.com/xid/0is5kqbx5kczzusum14y6-j0ussi


https://wolfram.com/xid/0is5kqbx5kczzusum14y6-jrcqcv


https://wolfram.com/xid/0is5kqbx5kczzusum14y6-5kfgm6


https://wolfram.com/xid/0is5kqbx5kczzusum14y6-76krta

Scope (14)Survey of the scope of standard use cases
Basic Uses (9)
Simulate an ensemble of random paths for a Cox–Ingersoll–Ross process:

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-bexgpm


https://wolfram.com/xid/0is5kqbx5kczzusum14y6-mn15g5

Simulate with arbitrary precision:

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-big92j

Compare paths for different values of the drift parameter:

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-2vtftp

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-1hrt14

Compare paths for different values of the volatility parameter:

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-7tifxi

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-mo6pzv

Compare paths for different values of the speed adjustment parameter:

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-sbqrn8

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-lg9qdx

Simulate a Cox–Ingersoll–Ross process with different starting points:

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-0pbe4h

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-37l3wb

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-sl7ej3


https://wolfram.com/xid/0is5kqbx5kczzusum14y6-b4q52

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-e93vf3


https://wolfram.com/xid/0is5kqbx5kczzusum14y6-45h9gs

Absolute correlation function:

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-r4jeh4

Process Slice Properties (5)
First-order probability density function for the slice distribution:

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-2st24h

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-k1o1wh

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-oegzkg


https://wolfram.com/xid/0is5kqbx5kczzusum14y6-ej3ae1

Multivariate slice distributions:

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-o8jlev


https://wolfram.com/xid/0is5kqbx5kczzusum14y6-bkhq1j

Compute the expectation of an expression:

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-edmw6r

Calculate the probability of an event:

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-miucta


https://wolfram.com/xid/0is5kqbx5kczzusum14y6-xgr42o


https://wolfram.com/xid/0is5kqbx5kczzusum14y6-bmnu2m


https://wolfram.com/xid/0is5kqbx5kczzusum14y6-84cmmy


https://wolfram.com/xid/0is5kqbx5kczzusum14y6-kupkj


https://wolfram.com/xid/0is5kqbx5kczzusum14y6-6jz3hy

CentralMoment and its generating function:

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-eawm2x


https://wolfram.com/xid/0is5kqbx5kczzusum14y6-j6j83y

FactorialMoment and its generating function:

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-o10xs2


https://wolfram.com/xid/0is5kqbx5kczzusum14y6-qux587

Cumulant and its generating function:

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-fmfg53


https://wolfram.com/xid/0is5kqbx5kczzusum14y6-sddn3s

Properties & Relations (3)Properties of the function, and connections to other functions
A Cox–ingersoll–Ross process is not weakly stationary:

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-qkojiz

Conditional cumulative distribution function:

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-ih0g5c

A Cox–ingersoll–Ross process is a special ItoProcess:

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-b8dpyf

As well as StratonovichProcess:

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-fx97pi

Neat Examples (3)Surprising or curious use cases
Simulate a Cox–Ingersoll–Ross process in two dimensions:

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-2tpc38

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-glj5f0

Simulate a Cox–Ingersoll–Ross process in three dimensions:

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-k9tdgg

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-qim6n8

Simulate 500 paths from a Cox–Ingersoll–Ross process:

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-q7hoj9
Take a slice at 1 and visualize its distribution:

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-8s9gfo

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-g5fe1v
Plot paths and histogram distribution of the slice distribution at 1:

https://wolfram.com/xid/0is5kqbx5kczzusum14y6-kwifgz

Wolfram Research (2012), CoxIngersollRossProcess, Wolfram Language function, https://reference.wolfram.com/language/ref/CoxIngersollRossProcess.html.
Text
Wolfram Research (2012), CoxIngersollRossProcess, Wolfram Language function, https://reference.wolfram.com/language/ref/CoxIngersollRossProcess.html.
Wolfram Research (2012), CoxIngersollRossProcess, Wolfram Language function, https://reference.wolfram.com/language/ref/CoxIngersollRossProcess.html.
CMS
Wolfram Language. 2012. "CoxIngersollRossProcess." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/CoxIngersollRossProcess.html.
Wolfram Language. 2012. "CoxIngersollRossProcess." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/CoxIngersollRossProcess.html.
APA
Wolfram Language. (2012). CoxIngersollRossProcess. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/CoxIngersollRossProcess.html
Wolfram Language. (2012). CoxIngersollRossProcess. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/CoxIngersollRossProcess.html
BibTeX
@misc{reference.wolfram_2025_coxingersollrossprocess, author="Wolfram Research", title="{CoxIngersollRossProcess}", year="2012", howpublished="\url{https://reference.wolfram.com/language/ref/CoxIngersollRossProcess.html}", note=[Accessed: 28-April-2025
]}
BibLaTeX
@online{reference.wolfram_2025_coxingersollrossprocess, organization={Wolfram Research}, title={CoxIngersollRossProcess}, year={2012}, url={https://reference.wolfram.com/language/ref/CoxIngersollRossProcess.html}, note=[Accessed: 28-April-2025
]}