Table 2.

Pairwise comparison of Y2H datasets

References	Ito et al. [1]	Cagney et al. [2]	Tong et al. [3]	Hazbun et al. [4]	Zhao et al. [5]	Uetz et al. [6] Experiment 1	Uetz et al. [6] Experiment 2
[1]	-	9	7	24	1	224	47
[2]	28	-	0	0	0	7	3
[3]	34	0	-	0	0	4	7
[4]	856	14	25	-	0	15	12
[5]	43	1	2	38	-	0	0
[6] Experiment 1	388	14	22	272	15	-	36
[6] Experiment 2	200	9	26	204	13	108	-

The values above the diagonal give the number of viable baits in common between each pair of experiments, and the values below the diagonal give the number of viable prey in common. We see that the overlap between experiments in the sampled fractions of protein- interaction space is in all cases very small, given that thousands of interactions were assayed.