Random Variable

AAA

DEFINITION of 'Random Variable'

A variable whose value is unknown or a function that assigns values to each of an experiment's outcomes. Random variables are often designated by letters and can be classified as discrete, which are variables that have specific values, or continuous, which are variables that can have any values within a continuous range.

INVESTOPEDIA EXPLAINS 'Random Variable'

Consider an experiment where a coin is tossed three times. If X represents the number of times that the coin comes up heads, then X is a discrete random variable that can only have the values 0,1,2,3 (from no heads in three successive coin tosses, to all heads). No other value is possible for X.


An example of a continuous random variable would be an experiment that involves measuring the amount of rainfall in a city over a year, or the average height of a random group of 25 people.




RELATED TERMS
  1. Discrete Distribution

    The statistical or probabilistic properties of observable (either ...
  2. Nonparametric Statistics

    A statistical method wherein the data is not required to fit ...
  3. Normal Distribution

    A probability distribution that plots all of its values in a ...
  4. Probability Distribution

    A statistical function that describes all the possible values ...
  5. Scenario Analysis

    The process of estimating the expected value of a portfolio after ...
  6. Credibility Theory

    Tools, policies, and procedures used by actuaries when examining ...
Related Articles
  1. Investing Basics

    What Are The Odds Of Scoring A Winning Trade?

    Just because you're on a winning streak doesn't mean you're a skilled trader. Find out why.
  2. Fundamental Analysis

    Financial Markets: Random, Cyclical Or Both?

    Are the markets random or cyclical? It depends on who you ask. Here, we go over both sides of the argument.
  3. Forex Education

    Trading With Gaussian Models Of Statistics

    The entire study of statistics originated from Gauss and allowed us to understand markets, prices and probabilities, among other applications.
  4. Trading Strategies

    What Your Trading Charts Aren't Telling You

    You may be missing some key statistics when following charts in the market.
  5. Professionals

    How do companies measure labor supply in human resources planning?

    Find out how and why a company's human resources department would measure labor supply, and what policies would address a shortage or surplus.
  6. Fundamental Analysis

    Why are OTC (over-the-counter) transactions controversial?

    Learn more about over-the-counter transactions, and why OTC traders are considered riskier than traders working with larger market exchanges.
  7. Fundamental Analysis

    What is the difference between cost of equity and cost of capital?

    Read about some of the differences between a company's cost of equity and its cost of capital, two measures of its required returns on raised capital.
  8. Fundamental Analysis

    What is arbitrage pricing theory?

    Find out what arbitrage pricing theory is and how it can theoretically be used by investors to generate risk-free profit opportunities.
  9. Fundamental Analysis

    What does a high weighted average cost of capital (WACC) signify?

    Find out what it means for a company to have a relatively high weighted average cost of capital, or WACC, and why this is important to lenders and investors.
  10. Fundamental Analysis

    How do economists and psychologists calculate diminishing marginal utility differently?

    Find out why disagreements about the validity of the law of diminishing marginal utility usually boil down to arguments about definitions.

You May Also Like

Hot Definitions
  1. Command Economy

    A system where the government, rather than the free market, determines what goods should be produced, how much should be ...
  2. Prospectus

    A formal legal document, which is required by and filed with the Securities and Exchange Commission, that provides details ...
  3. Treasury Bond - T-Bond

    A marketable, fixed-interest U.S. government debt security with a maturity of more than 10 years. Treasury bonds make interest ...
  4. Weight Of Ice, Snow Or Sleet Insurance

    Financial protection against damage caused to property by winter weather specifically, damage caused if a roof caves in because ...
  5. Weather Insurance

    A type of protection against a financial loss that may be incurred because of rain, snow, storms, wind, fog, undesirable ...
  6. Portfolio Turnover

    A measure of how frequently assets within a fund are bought and sold by the managers. Portfolio turnover is calculated by ...
Trading Center