Table 1.

Characteristics and sources of the four test data-sets, columns from left to right show: data-set, lengths, mean pair-wise sequence similarity (mean pair-wise Kimura "2-parameter" distance is shown in parentheses [109]), the number of sequences in each alignment and the alignment and structure sources are given.

		Test data-set characteristics and sources
Data-set	length	mean pairwise seq. identity		Number of Sequences		Alignment source	Structure source
		High	Med.	High	Med.
E. coli LSU rRNA	2904	88.1 (0.12)	72.0 (0.35)	11	11	Wuyts et al., (2001)	Cannone et al., (2002)
E. coli SSU rRNA	1542	90.7 (0.08)	80.0 (0.21)	11	11	Wuyts et al., (2002)	Cannone et al., (2002)
E. coli RNase P	377	81.5 (0.09)	67.1 (0.41)	9	11	Brown, (1999)	Brown, (1999)
S. cerevisiae tRNA-PHE	73	84.4 (0.19)	60.0 (0.71)	11	11	Griffiths-Jones et al., (2003)	Sundaralingham & Rao, (1975)