Principal components analysis

3.6 Explanation.

Cite Allison Horst’s whale figure here.

3.6.1 Questions and data types

3.6.2 Key assumptions

3.6.3 Key distinctions among methods within PCA

3.7 email text

3.7.1 CART/ctree explanations

- Start with this one, CART section mainly: [http://www.jstor.org/stable/10.1086/587826](http://www.jstor.org/stable/10.1086/587826)
    
- [https://stats.stackexchange.com/questions/12140/conditional-inference-trees-vs-traditional-decision-trees](https://stats.stackexchange.com/questions/12140/conditional-inference-trees-vs-traditional-decision-trees)
    
- [https://stats.stackexchange.com/questions/255150/how-to-interpret-this-decision-tree](https://stats.stackexchange.com/questions/255150/how-to-interpret-this-decision-tree)
    

3.7.2 Examples of PCA in the wild:

- [https://esajournals.onlinelibrary.wiley.com/doi/full/10.1890/1051-0761%282006%29016%5B0687%3AHELMAR%5D2.0.CO%3B2](https://esajournals.onlinelibrary.wiley.com/doi/full/10.1890/1051-0761%282006%29016%5B0687%3AHELMAR%5D2.0.CO%3B2)
    
- Uses R’s ctree: [https://link.springer.com/article/10.1007/s11252-019-00896-0](https://link.springer.com/article/10.1007/s11252-019-00896-0)

3.7.3 Once you have decided to use it, check implementation