Table 1

Percentage of input space covered by training instances for various alphabet sizes (CN feature)

# letters

Ratio

2

100%

3

97.8%

4

57.6%

5

11.3%

20

3.1e^-7

Bacardit et al. BMC Bioinformatics 2009 10:6   doi:10.1186/1471-2105-10-6