Table 7. The values of log-likelihood (l), d N/d S, and parameter estimates in CODEML analysis of swine A(H1N1) HAs between 1990–2009.
| Model | l | d N/d S | Parameters estimates | LRT (2Δl) (p-values) |
| M0 (one-ratio) | −6021.08 | 0.158 | ω = 0.158 | |
| M1a (nearly neutral) | −5949.30 | 0.217 | p 0 = 0.864 (p 1 = 0.136), ω0 = 0.094 (ω1 = 1) | LRT (M2a-M1a) = 1.24 (0.5379) |
| M2a (positive selection) | −5948.68 | 0.224 | p 0 = 0.864, p 1 = 0.134 (p 2 = 0.002), ω0 = 0.095 (ω1 = 1), ω2 = 3.682 | |
| M7 (beta) | −5925.79 | 0.174 | P = 0.381, q = 1.768 | LRT (M8-M7) = 6.78 (0.0337) LRT (M8-M8a) = 3.40 (0.0326) |
| M8a (beta&ω = 1) | −5924.10 | 0.171 | p 0 = 0.970 (p 1 = 0.030), p = 0.460, q = 2.617, ωs = 1 | |
| M8 (beta&ω) | −5922.40 | 0.177 | p 0 = 0.995 (p 1 = 0.005), p = 0.413, q = 2.052, ωs = 2.546 |
The analysis was performed on the first 338 residues of HA1 including the signal peptide.