Table 7. R-Index for 4-letter identifiers.

	5	4	3	2	1
5	1.000000	0.397765	0.330680	0.285021	0.234393
4	0.602235	1.000000	0.441875	0.372183	0.294190
3	0.669320	0.558125	1.000000	0.444156	0.334842
2	0.714979	0.627817	0.555844	1.000000	0.393229
1	0.765607	0.705810	0.665158	0.606771	1.000000