Edit: I see now these graphs are really large, I'll post smaller going forward, or use thumbnails.
Price stitching is hard
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Let me look into this and get back to you. It is hard.... especially fully automated!
GAT
I had some mismatches in the 2 processes I use (moving to a new process now that I got some price data going back in history) so I wanted to see what Rob's prices look like from pysystemtrade repo, to break the tie. First graph above is VSTOXX.
All is good in the land of bonds tho, not many ways to mess it up
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But then I stumbled upon Lean Hogs:
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Doing some more digging, Rob, I think there might be something wonky happening with your price data in pysystemtrade with lean hogs. Prior to 2014, there are some weird rolling schedules, for example, here's an entry from multiple prices CSV:
Code:
2014-02-24 15:51:57,,20140600,,20130700,107.7375,20140700
Seems like you're using July 2013 for carry, but that would have been long expired. I checked your roll calendar config for this, and looks like for a bunch of years prior to 2014, you were rolling only twice a year, in April and May.
Not sure if that's intentional or not, just wanted to give you a heads up.
Besides this, I checked 11 other instruments over a period from 1/1/2001 until today, and our adjusted prices match closely. Some deviation is expected of course, as we don't roll on exact same days.