Random Variable

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.



comments powered by Disqus
Hot Definitions
  1. Ascending Triangle

    A bullish chart pattern used in technical analysis that is easily recognizable by the distinct shape created by two trendlines. In an ascending triangle, one trendline is drawn horizontally at a level that has historically prevented the price from heading higher, while the second trendline connects a series of increasing troughs.
  2. National Best Bid and Offer - NBBO

    A term applying to the SEC requirement that brokers must guarantee customers the best available ask price when they buy securities and the best available bid price when they sell securities.
  3. Maintenance Margin

    The minimum amount of equity that must be maintained in a margin account. In the context of the NYSE and FINRA, after an investor has bought securities on margin, the minimum required level of margin is 25% of the total market value of the securities in the margin account.
  4. Leased Bank Guarantee

    A bank guarantee that is leased to a third party for a specific fee. The issuing bank will conduct due diligence on the creditworthiness of the customer looking to secure a bank guarantee, then lease a guarantee to that customer for a set amount of money and over a set period of time, typically less than two years.
  5. Degree Of Financial Leverage - DFL

    A ratio that measures the sensitivity of a company’s earnings per share (EPS) to fluctuations in its operating income, as a result of changes in its capital structure. Degree of Financial Leverage (DFL) measures the percentage change in EPS for a unit change in earnings before interest and taxes (EBIT).
  6. Jeff Bezos

    Self-made billionaire Jeff Bezos is famous for founding online retail giant Amazon.com.
Trading Center