course
/
r4ds
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

A few more model ideas

This commit is contained in:
hadley 2016-07-06 17:57:03 -05:00
parent f2255f39c7
commit d8f0c87ecf
2 changed files with 3 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
intro.Rmd
View File

@ -84,6 +84,7 @@ This book focuses exclusively on structured data sets: collections of values tha
Exploratory vs. confirmatory
Most people think of models as confirmatory and visualisations as exploratory. But you can have confirmatory visualisations and exploratory models. This book focuses on exploration.
### Formal Statistics and Machine Learning

2
model-basics.Rmd
View File

@ -2,6 +2,8 @@
The goal of a fitted model is to provide a simple low-dimensional summary of a dataset. Ideally, the fitted model will capture true "signals" (i.e. patterns generated by the phenomenon of interest), and ignore "noise" (i.e. random variation that you're not interested in).
A model is a tool for making predictions. Goal of a model is to be simple and useful.
This is a hard problem because any fitted dataset is just the "best" (closest) model from a family of models. Just because it's the best model doesn't make it good. And it certainly doesn't imply that the model is true. But a model doesn't need to be true to be useful. You've probably heard George Box's famous aphorism:
> All models are worng, but some are useful.