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  1. Q

    AIC models

    Hello, If I have a model with an aic of 8765 and another model reduced with two variables less with an aic of 8823. Can I accept the reduced model with the AIC of 8823? What is the difference between the two AICs that should not be exceeded? Thank you
  2. Q

    Generalized linear model: application conditions

    Hello all, I would like to know what the conditions are for the application of a GLM. Should we test if the response variable is normally distributed? (shapiro wilk) Is it a problem if my variables are correlated with each other but my observations are not? Thanks
  3. Q

    Testing log-linearity

    Hi all, I want to test the log-linearity assumption for a cox model. How to interpret the plot of martingale residuals? you need to have a horizontal plot, or a linear line, or ... In which case should the hypothesis be validated and in which case should it not be validated?
  4. Q

    Cox Regression Assumption

    Hi all, My Cox regression model doesn't validate the proportional hazards hypothesis. I think the other two assumptions are easy to verify. I used the 'strata' function in my model [ strata(hospital) ], but the proportional hazards assumption is still not validated. How can I do to validate...
  5. Q

    How to find the best regression model

    Hi all, I would like to know, how to find the best regression model ? I have different models with different variables. I would like to know which of them is the "best" to use. The lowest AIC value is enough to determine the 'best' model ?