# Selection Bias

*Math & Statistics — Finicade finance glossary*

Selection bias is when the sample you analyse isn't representative of the population you want to describe, so the answer is wrong before any statistics are run. Voluntary surveys capture people with strong opinions; a study of clients captures only those who stayed. No amount of sample size fixes it — a larger biased sample simply produces a more confident wrong answer.

**Also known as:** sampling bias, non-response bias

**Related terms:** [Survivorship Bias](https://finicade.com/glossary/survivorship-bias), [Sampling](https://finicade.com/glossary/sampling), [Omitted Variable Bias](https://finicade.com/glossary/omitted-variable-bias), [Endogeneity](https://finicade.com/glossary/endogeneity), [Correlation vs Causation](https://finicade.com/glossary/correlation-vs-causation)

Source: https://finicade.com/glossary/selection-bias