Table 2.

Model fits.

infection model	parameter estimatesa	log likelihood, l
mass-action	b=(2.12±0.17)×10−5 ml d−1	−374.5
parasite antagonism	$\tilde{b}=(5.20\pm 0.40)\times {10}^{-2}{\text{ml}}^k{\text{d}}^{-\text{1}},k=0.367\pm 0.007$	−185.1
heterogeneous host	$\overline{b}=(6.49\pm 1.24)\times {10}^{-4}\text{ml}{\text{d}}^{-\text{1}},v=2.13\pm 0.22$	−173.0

^aMaximum-likelihood estimates±s.e.