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.

Discrete Distribution
The statistical or probabilistic properties of observable (either ... 
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How does the market share of a few companies affect the HerfindahlHirschman Index ...
In economics and commercial law, the HerfindahlHirschman Index (HHI) is a widely used measure that indicates the amount ... Read Full Answer >> 
What does the rule of 70 indicate about a country's future economic growth?
The rule of 70 could be used to indicate the approximate number of years that it would take a company's economic growth to ... Read Full Answer >> 
How is the rule of 70 related to the growth rate of a variable?
The rule of 70 is related to the growth rate of a variable because it uses the growth rate in its approximation of the number ... Read Full Answer >> 
What is a "linear" exposure in Value at Risk (VaR) calculation?
A linear exposure in the valueatrisk, or VaR, calculation is represented by positions in stocks, bonds, commodities or ... Read Full Answer >> 
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 >> 
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 >>

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