Distributions & Models Vocabulary

a symmetric bell-shaped probability distribution

“Heights in a population follow approximately a normal distribution.”

relating to experiments with two possible outcomes

“The number of successes in n trials follows a binomial distribution.”

a distribution modeling rare events over fixed intervals

“The number of calls per hour follows a Poisson distribution.”

a distribution modeling time between events in a Poisson process

“Wait times often follow an exponential distribution.”

a distribution where all outcomes are equally likely

“A fair die has a discrete uniform distribution.”

a measure of asymmetry in a probability distribution

“Income distributions typically show positive skewness.”

a measure of the 'tailedness' of a probability distribution

“High kurtosis indicates more extreme outliers.”

involving two or more random variables

“Multivariate analysis considers multiple variables simultaneously.”

the value below which a given percentage of observations fall

“Scoring in the 95th percentile means outperforming 95% of test-takers.”

an observation that lies far from other values

“The billionaire's income is an outlier in the dataset.”