Dako wrote:Also, if you add criteria with 3 wars completed - then the results should be much better.
In one of the ELO versions I had, I used a display factor of (.5 for wars of 1 or 2, .75 if 3 wars and 1.00 if 4 or more wars) You could do something like that. I called it a Reliability Rating.
This is definitely a good idea. I appreciate you testing out this metric and your feedback, as I know you have a lot of experience doing this.
I came across the algorithm of 400 by playing chess online on Gameknot. The way they implemented it, if you played under 10 games, your score was computed the same as everybody else, but it was noted as being "provisional". Perhaps I could add option to include/exclude provisional clans from the ranking list.
jpcloet wrote:I used all of time, so I set it to 5 years.
It's not necessary to set it to 5 years if you want to take 5 year-old data into consideration. It's a bit confusing. It will help if I explain a little of what exactly the program does.
The way the program works, it starts at the first challenge, no matter what the Data Window value, and adds challenge by challenge, recomputing each clan's rating as it goes.
In order for this to work, every time I calculate the rating for a clan, I must pass a time parameter. The time parameter specifies what point in time I am calculating the rating. This is the date used to establish the data window that determines which challenges are counted.
Each clan war provides one data point
, which is either +/- 400 of the opponent clan's rating at the time of the challenge. For ties, the opponent's rating is used unaltered. Data points are dated to the time of conclusion of the challenge.
For example, when I calculate THOTA's rating for Mar 25, 2007, it will only be looking at challenges that happened prior to that date. If Data Window is set to 1 year, the rating will be computed by games-weighted averaging the data points (i.e. results from challenges) between Mar 25, 2006 and Mar 25, 2007. However, given that one of these THOTA challenges (against Z-Nihilists) concluded on June 6, 2006, the value of that data point would be based on Z-Nihilists rating at that time (June 6, 2006), meaning it would have been computed by averaging data points of the Z-Nihilists' challenges between June 6, 2005 and June 6, 2006. If the Z-Nihilists played against Z-Beelzebubs on July 14, 2005, it would then need to calculate rating of Z-Beelzebubs on July 14, 2005. This required looking at all of Z-Beelzebubs' challenges between July 14, 2004 and July 14, 2005. And so on and so forth until the beginning of time.
So since it starts at the beginning, you can be assured that all 5 years of data will be used as the algorithm computes and recomputes ratings over the past 5 years no matter what the Data Window setting.