Table 3.

Model comparison results. Models of cognate gain and loss included are (i) CTMC; (ii) CTMC plus γ rate heterogeneity with four rate categories (CTMC + γ); (iii) binary covarion (Covarion); (iv) stochastic Dollo (Dollo). Models of tree rate variation are (i) strict clock (strict); (ii) relaxed clock with rates sampled from lognormal distribution (relaxed). Models of concept rate variation are (i) relative mutation rate estimated for individual concepts (word rates); (ii) no relative mutation rate estimated (overall rate).

analysis	model	clock	mutation rates	marginal log-likelihood	difference	BayesFactor (2 × ln(K))
cov-est-relax	Covarion	relaxed	word rates	−4128	—	—
ctmc-est-relax	CTMC	relaxed	word rates	−4131	−3	6
ctmc4 g-est-relax	CTMC + γ	relaxed	word rates	−4136	−4	8
cov-fixed-relax	Covarion	relaxed	overall rate	−4147	−11	22
ctmc4 g-fixed-relax	CTMC + γ	relaxed	overall rate	−4153	−6	12
cov-est-strict	Covarion	strict	word rates	−4182	−29	58
ctmc-est-strict	CTMC	strict	word rates	−4185	−3	6
ctmc4 g-est-strict	CTMC + γ	strict	word rates	−4191	−6	12
ctmc-fixed-relax	CTMC	relaxed	overall rate	−4234	−43	86
sdollo-est-relax	Dollo	relaxed	word rates	−4540	−306	612