Help! My model fits too well!
This is sort-of related to my sidelined study of graph algebra. I was thinking about data I could apply a first-order linear difference model to, and the stock market came to mind. After all, despite some black swan sized shocks, what better predicts a day’s closing than the previous ...
![](https://www.r-bloggers.com/wp-content/uploads/2010/10/Plotoffirstdifference.jpg)