# 10: OLS Assumptions and Simple Regression Diagnostics

- Page ID
- 7246

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- 10.2: When Things Go Bad with Residuals
- Residual analysis is the process of looking for signature patterns in the residuals that are indicative of a failure in the underlying assumptions of OLS regression. Different kinds of problems lead to different patterns in the residuals.

- 10.3: Application of Residual Diagnostics
- This far we have used rather simple illustrations of residual diagnostics and the kinds of patterns to look for. But you should be warned that, in real applications, the patterns are rarely so clear.