control variables

How Simple Should a Model Be? The Case of Insignificant Controls, Interactions, and Covariance Structures

September 23rd, 2011 by

Everything should be made as simple as possible, but no simpler” – Albert Einstein*Stage 2

For some reason, I’ve heard this quotation 3 times in the past 3 days.  Maybe I hear it everyday, but only noticed because I’ve been working with a few clients on model selection, and deciding how much to simplify a model.

And when the quotation fits, use it. (That’s the saying, right?)

*For the record, a quick web search indicated this may be a paraphrase, but it still applies.

The quotation is the general goal of model selection.  You really do want the model to be as simple as possible, but still able to answer the research question of interest.

This applies to many areas of model selection.  Here are a few examples: (more…)