AP Statistics

Probability Distributions

Learn Probability Distributions in AP Statistics from the production AIPH study guide.

Advanced Topics

In a nutshell: Probability distributions let us model and predict real-world randomness.

## Understanding Distributions A probability distribution shows all possible outcomes and their probabilities. ## Common Distributions - **Binomial distribution**: Counts successes in a fixed number of trials. - **Normal distribution**: The famous 'bell curve', important in many natural phenomena. ## The Normal Distribution - Symmetrical and centered at the mean. - About 68% of values fall within one standard deviation of the mean. \[ Z = \frac{X - \mu}{\sigma} \] ## Applications Probability distributions help with making predictions, setting quality controls, and analyzing risks.

Examples

  • A company uses the normal distribution to assess product quality.
  • A sports analyst models the number of goals in games with a binomial distribution.

Key terms

Standard deviation
A measure of how much data varies from the mean.
Normal distribution
A symmetric, bell-shaped distribution important in statistics.