Stochastic processes are a fundamental concept in probability theory and statistics. They are used to model systems that evolve over time in a random manner. This tutorial will provide an overview of stochastic processes, including their definition, types, and applications.

Definition

A stochastic process is a collection of random variables indexed in a manner that reflects some time sequence, and usually defined on a probability space.

Types of Stochastic Processes

1. Markov Processes

Markov processes are a class of stochastic processes that have the Markov property. This property states that the future state of the process depends only on the current state and not on the sequence of events that preceded it.

2. Poisson Processes

Poisson processes are used to model the number of events that occur in a fixed interval of time and space.

3. Brownian Motion

Brownian motion is a continuous-time stochastic process that is often used to model the movement of particles in a fluid.

Applications

Stochastic processes are widely used in various fields, including finance, physics, biology, and engineering. Here are a few examples:

  • Finance: Stochastic processes are used to model stock prices and option prices.
  • Physics: Stochastic processes are used to model the motion of particles in a fluid.
  • Biology: Stochastic processes are used to model the growth of populations and the spread of diseases.
  • Engineering: Stochastic processes are used to model the reliability of systems and the performance of networks.

For more information on stochastic processes, you can visit our probability theory tutorials.

Brownian Motion