# Statistics - Chance

The chance effect in Statistics is represented by the sampling error.

When something is unsystematic, it's then due to chance. If an error is systematic, it's a bias.

The chance probability is:

• 50% for a two binary event (tossing a coin).
• 33% for a three class classification

Chance is another word for random.

## Documentation / Reference

* If you’re so smart, why aren’t you rich? Turns out it’s just chance

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