# is there a way to plot best glm model in model selection

I have run this glm model

y~poly(xa,2)+poly(xb,2)+...

Then have found the best fitting model using AICc. The best fitting model has a subset of the x variables.

How do I show that the model fits well the data? With y and x it's easy but now I have y and xa, xb, etc. and these x variables are values on different scales. Do I just say this was the best performing models in my manuscript or do I have to present a graph?

• How exactly was your model chosen? (This is your rationale for choosing this model so it is important and you want to describe this part.) How do you define "the best" model in this case? How do you define model performance? Answering this questions is crucial to what you are going to describe and how to visualize your results.
– Tim
Jan 27, 2015 at 12:17
• @Tim I have specified that I have compared models using AICc. Is that what you are asking? I picked the model with the lowest AIC and used a step function. Jan 27, 2015 at 16:43
• Stepwise regression is not the best approach: stata.com/support/faqs/statistics/stepwise-regression-problems or andrewgelman.com/2014/06/02/hate-stepwise-regression
– Tim
Jan 27, 2015 at 16:56
• @Tim thanks for the feedback, I have read that information but in Biology it seems that AICc and stepwise regression is accepted even in recent publications. Jan 27, 2015 at 17:52
• In psychology it is accepted to treat single 5-point likert item as continuous and normally distributed...
– Tim
Jan 27, 2015 at 18:18