Probability distribution
Probability distribution specifies every value a random variable can take and the probability of each. Discrete distributions list outcomes with probabilities that sum to one.
Also known asdistribution
What it is
See it move
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A split bar divides a total probability of 1.00 into three segments representing the values of a customer-satisfaction probability mass function: Score 1 receives probability 0.20, Score 2 receives 0.50, and Score 3 receives 0.30. The bar conveys the defining property of a probability distribution: each possible value is assigned a non-negative probability and all probabilities together sum to exactly 1.00.
Check yourself
PracticeCORE
A random variable X can take only the values 1, 2, or 3. Which of the following is a valid probability distribution for X?
Select an answer to check your understanding.