Quantitude S1E14: Model Fit & The Curse of the Black Pearl
Feb 11, 2020
Patrick and Greg discuss model fit in structural equation models, compulsive counting, mashed potatoes, building model 747s, Jenga, Moses's tablet, the Pirate Code, demon conferences, and Roo Mates.
AI Snips
Chapters
Transcript
Episode notes
Models Are Simplifications by Design
- A model is a simplified representation of a complex reality by design.
- All models are inherently wrong but aim to balance simplicity with fidelity to data.
Degrees of Freedom as Courage
- Multiple regression models fit data perfectly because they impose no restrictions and have zero degrees of freedom.
- Degrees of freedom measure the imposition of constraints, reflecting the courage of the modeler.
Understanding Model Fit in SEM
- Fit means how well a whole system of variables reproduces observed relations, not just explaining variance in one variable.
- Structural equation models with no restrictions fit perfectly by default, challenging traditional notions of fit.