Free downloadable book on computational modeling

It's mighty scant at this point, but it includes plenty of problems for people who might want to challenge themselves and improve their understanding of the topics. And it's at Version 0.0.10... it has a ways to go. It's all done in Python too, for anyone who might be interested in Python.

I'd probably do everything in R though.

Its the simple things

vs.



I found it really difficult to tell when the trend was negative or positive without a good 0-line. Also, you probably only have to label every few month labels, like Jan., Apr., July., Oct. - the current axis makes everything all crowded.

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