# Marginal Probability Distribution

Harry Potter and the Sorcerer's Stone, Book 1 on Audible

As an Amazon Associate I earn from qualifying purchases. Thank you!

**Formula:**`P(A) = ∑ P(A, B=j); j=1 to n`

## Introduction to Marginal Probability Distribution

The marginal probability distribution is a statistical concept used in probability theory, which describes the probability of an event occurring irrespective of the outcome of another random variable. The formula is derived from the joint probability distribution by summing the probabilities of the events that have the same value of the variable of interest, while allowing the other variable of the joint event to vary freely. This concept is widely used in fields such as finance, engineering, and social sciences for analyzing the likelihood of independent events or variables.

## Parameter usage:

`probabilityX`

= probability of event X`probabilityY`

= probability of event Y

## Output:

`P(A)`

= marginal probability of event A

## Data validation

The probabilities should be between 0 and 1.

## Summary

This formula calculates the marginal probability distribution of two independent events, providing insights into the individual probabilities regardless of other variables.

Tags: Probability, Statistics, Distribution