I am studying relationship between strength of a player and his games, (e.g. for automatic ranking based on a few games). For this I am in need of a large collection of games, for players of various strengths, but with the requirement, that the ranking system is the same across all the games. I would like to use OGS (mostly because you have a lot of weaker players, unlike kgs for instance), but there has been some changes in the ranking system (and I do not know when). So I would like to ask, if you could reccomend time period when the ranking system was without changes for a longer time (the more recent, the better)
I came across (was reccomended to me by Ray) this repository
which has a lot of games, BUT the author notes that on 9.4.2014 there has been a recalibration of the ranking system, so I would need to use either games before of after. This might not be a problem, but I would rather:
- use more recent games ( e.g. so that I could offer the automatic rank calibration for players with only a few games to OGS)
- have some dev confirm an interval without changes (even subtle changes bring error to the ML process)
Thanks a lot!