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R functions p q d r

R Functions

Source Every distribution in R has 4 functions. (Basically, 4 prefixes + name of the distribution.)

Use Case Function Name Description Layman Explanation
Continuous p Probability Cumulative Distribution Function (CDF) "What is the probability above or below a cutoff?"
Continuous q Quantile Inverse CDF "What value corresponds to, say, 80% of the way to the maximal value?"
Both d Density Density function (PMF for discrete, PDF for continuous) "What is the 'height' or y-value of the distribution at a specific point?"
Both r Random Random Variable Generator "Generate random values following this distribution."