Introducing the Math of Conditional Probability

My recent Decoded Science article, “An Introduction to Conditional Probability in Mathematics“, continues my series about probability.

Probability versus Conditional Probability

Four Random Dice, image by dullhunk
Four Random Dice, image by dullhunk

The idea behind “conditional probability” is that one event might become more or less likely to occur, given something else that has already happened. For example, if you need to roll a total of 9 or higher with two consecutive dice rolls, your chances improve if the first roll is high, but plummet to zero if the first number shown is ‘1’ or ‘2’.

On the other hand, your odds of success should not be affected by last night’s lottery selection. The probability of winning that jackpot is simply an incredibly small number, and can be calculated separately.

In my Blog of Writing, “Preview of Conditional Probability” also provides a useful writing tip.

(Updated 2012-01-17) As I explain in “Preview of Non-Commutative Conditional Probability“, I will also include a link to one article that I used for reference:

Weisstein, Eric W. “Conditional Probability” From MathWorld–A Wolfram Web Resource.

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Thank you for reading about the mathematics of conditional probability.

44 thoughts on “Introducing the Math of Conditional Probability”

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