# Posts Tagged ‘ ACT6420-A2012 ’

## On Box-Cox transform in regression models

November 13, 2012
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$Y_i=\beta_0+\beta_1 X_i+\varepsilon_i$

A few days ago, a former student of mine, David, contacted me about Box-Cox tests in linear models. It made me look more carefully at the test, and I do not understand what is computed, to be honest. Let us start with something simple, like a linea...

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## Why pictures are so important when modeling data?

October 31, 2012
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$R^2$

(bis repetita) Consider the following regression summary,Call: lm(formula = y1 ~ x1)   Coefficients: Estimate Std. Error t value Pr(>|t|) (Intercept) 3.0001 1.1247 2.667 0.02573 * x1 0.5001 0.1179 4.241 0.00217 **...

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