discrete variable

statistics

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June 25, 2026

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In statistics, a discrete variable is a type of random variable that can only take on a finite or countably infinite number of distinct values. These values are separate and unconnected, meaning there are gaps between them.12

For example, when tossing three coins, the number of heads can only be 0, 1, 2, or 3. Each of these outcomes is a discrete value, and the probabilities associated with them sum to 1. This is in contrast to a continuous variable, which can take on any value within a given range, such as the life expectancy of a light bulb.1

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difference equation
…of a function of a discrete variable. A discrete variable is one that is defined or of interest only for values that differ by some finite amount, usually a constant and often 1; for example, the discrete variable x may have the values x₀ = a, x₁ = a +…
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…of a function of a discrete variable. A discrete variable is one that is defined or of interest only for values that differ by some finite amount, usually a constant and often 1; for example, the discrete variable x may have the values x₀ = a, x₁ = a +…
Read More