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Chapter07/videos.md

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 [Video 2. Linear and Polynomial Regression](https://www.youtube.com/watch?v=wfrfmDhxdXE) This video covers the implementation of the polynomial regression with a numerical example for linear regression model. The goodness of fit metrics such as r-squared, residual and PO plots, and 68 and 95% confidence intervals are also covered.
 
 [Video 3. Nonlinear (Linearizable) Least Squares Regression](https://www.youtube.com/watch?v=wG4J4nnjgxk) This video covers transformation techniques to convert complex or nonlinear models to linear models. Numerical solution of an example problem is given step-by-step with emphasis on calculating and assessing the goodness of fit metrics.
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+[Video 4. Multivariate Regression](https://www.youtube.com/watch?v=CXTDLgHHwgs) This video covers linear and exponential multivariate regression models. A numerical example, describing how to obtain a multivariate regression model and assess its goodness of fit, has been provided.