| Amino acids (n = 21) | Codons (n = 64) |
---|
 | Archaea/bacteria | Eukaryotes | Archaea/bacteria | Eukaryotes |
---|
 | Slope | Intercept | Slope | Intercept | Slope | Intercept | Slope | Intercept |
---|
Slope | - | 0.95 | - | 0.96 | - | 0.90 | - | 0.91 |
Correlation coefficient | 0.92 | 0.96 | 0.96 | 0.98 | 0.90 | 0.97 | 0.94 | 0.94 |
- All pairs of measures are highly correlated. Critical values: for amino acids (n = 21 including stop codons), r of 0.9 corresponds to P = 3 × 10 -8. For codons (n = 64), r of 0.9 corresponds to P = 5 × 10-24. The x intercept is transformed as x' = 1/(50% - x) to minimize the effects of extreme values with large errors: this occurs for codons and amino acids with very flat slopes.