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. Probability Distribution

    A statistical function that describes all the possible values ...
  4. Normal Distribution

    A probability distribution that plots all of its values in a ...
  5. Scenario Analysis

    The process of estimating the expected value of a portfolio after ...
  6. Cape Cod Method

    A method used to calculate loss reserves that uses weights proportional ...
RELATED FAQS
  1. What is a "linear" exposure in Value at Risk (VaR) calculation?

    A linear exposure in the value-at-risk, or VaR, calculation is represented by positions in stocks, bonds, commodities or ... Read Full Answer >>
  2. What is the criteria for a simple random sample?

    Simple random sampling is the most basic form of sampling and can be a component of more precise, more complex sampling methods. ... Read Full Answer >>
  3. What are some examples of ways that sensitivity analysis can be used?

    Sensitivity analysis is an analysis method that is used to identify how much variations in the input values for a given variable ... Read Full Answer >>
  4. What are the benefits of using ceteris paribus assumptions in economics?

    Most, though not all, economists rely on ceteris paribus conditions to build and test economic models. The reason they do ... Read Full Answer >>
  5. How is the 80-20 rule (Pareto's Principle) used in macroeconomics?

    The 80-20 rule was first used in macroeconomics to describe the distribution of wealth in Italy in the early 20th century, ... Read Full Answer >>
  6. What are some of the uses of the coefficient of variation (COV)?

    In statistics, the coefficient of variation (COV) is a simple measure of relative event dispersion. It is equal to the ratio ... Read Full Answer >>
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. Economics

    What is Deadweight Loss?

    Mainly used in economics, deadweight loss can be applied to any deficiency caused by an inefficient allocation of resources.
  6. Investing

    The Strong Dollar’s (Real) Toll On Tech Stocks

    A large portion of U.S. technology companies’ sales occur overseas, given the strong international business and consumer demand from many U.S. tech firms.
  7. Fundamental Analysis

    How to Calculate a Coverage Ratio

    In broad terms, the higher the coverage ratio, the better the ability of the enterprise to fulfill its obligations to its lenders.
  8. Economics

    How to Do a Cost-Benefit Analysis

    The benefits of a given situation or business-related action are summed and then the costs associated with taking that action are subtracted.
  9. Fundamental Analysis

    Calculating the Herfindahl-Hirschman Index (HHI)

    The Herfindhal-Hirschman Index, (HHI) is a measure of market concentration and competition among market participants.
  10. Fundamental Analysis

    Calculating Net Interest Margin

    Net interest margin is a metric used to measure the effectiveness of a company’s investment decisions, particularly financial institutions.

You May Also Like

Hot Definitions
  1. Moving Average - MA

    A widely used indicator in technical analysis that helps smooth out price action by filtering out the “noise” from random ...
  2. Yield Curve

    A line that plots the interest rates, at a set point in time, of bonds having equal credit quality, but differing maturity ...
  3. Productivity

    An economic measure of output per unit of input. Inputs include labor and capital, while output is typically measured in ...
  4. Variance

    The spread between numbers in a data set, measuring Variance is calculated by taking the differences between each number ...
  5. Terminal Value - TV

    The value of a bond at maturity, or of an asset at a specified, future valuation date, taking into account factors such as ...
  6. Rule Of 70

    A way to estimate the number of years it takes for a certain variable to double. The rule of 70 states that in order to estimate ...
Trading Center