Number of games in a rating window depending on window size in days

[flovo]

According to Prof. Glickman, glicko2 works best when there are 10-15 games in a rating period. In our player base this can be any between 27 and 55 days.

I calculated the median number of games based on the window size in days. I put the results here for reference. Only players with at least 30 rated games are considered. Only periods with at least 1 game are used when calculating the median.

window size in days	median number of games	rating days ( number of rating periods with at least one game times window width
1	2	5301557
2	3	7460412
3	3	8927646
4	4	10045968
5	4	10964225
6	4	11728704
7	5	12404581
8	5	12980944
9	5	13513113
10	5	13989680
11	6	14422034
12	6	14808804
13	6	15210078
14	7	15604414
15	7	15939495
16	7	16241776
17	7	16528879
18	8	16859700
19	8	17121945
20	8	17467900
21	8	17727759
22	8	17983724
23	9	18160938
24	9	18437232
25	9	18652825
26	9	18938790
27	10	19153611
28	10	19324872
29	10	19479851
30	10	19722210
31	11	19874782
32	11	20198176
33	11	20278071
34	11	20584892
35	11	20597080
36	12	21018852
37	12	21139099
38	12	21336772
39	12	21373833
40	12	21740400
41	13	21724629
42	13	22132488
43	13	22047390
44	13	22446776
45	13	22403070
46	14	22547866
47	14	22880070
48	14	23090880
49	14	23206890
50	15	23171950
51	15	23451483
52	15	23559172
53	15	23542971
54	15	23934150
55	15	24195215
56	16	24314024