Table 2.

Parameter estimates for generalized linear mixed models

(1) Effect of the number of months since parturition on the proportion of MS days
Unit: each 6-month period from parturition
Family: binomial (logit)
Formula: proportion of MS days and non-MS days ~ months from parturition + months from parturition squared + (1|female ID)
	Estimate	Std. Error	z value	Pr( >|z|)
(Intercept)	−0.75623	0.0928	−8.377	< 2e–16 ***
Months from parturition	−0.81452	0.03102	26.254	< 2e–16 ***
Months from parturition squared	−0.27692	0.02664	−10.395	< 2e–16 ***
(2) Effect of the number of months since parturition on the frequency of copulation
Unit: each 6-month period from parturition
Family: Poisson (log)
Formula: number of copulations ~ months from parturition + months from parturition squared + offset [log (number of observation days)] + (1|female ID)
	Estimate	Std. Error	z value	Pr( >|z|)
(Intercept)	−1.90034	0.23081	−8.233	< 2e–16 ***
Months from parturition	0.69700	0.03161	22.05	< 2e–16 ***
Months from parturition squared	−0.21739	0.02994	−7.261	3.83e–13***
(3) E1C concentrations at different swelling states
Unit: each urine sample
Formula: log (E1C concentration + 0.5) ~ swelling phase + (1|female ID)
	Estimate	Std. Error	df	t value	Pr( >|t|)
(Intercept)	2.17127	0.11445	8.28045	18.97	4.08e−08***
sw3 vs sw2	−0.38446	0.07323	473.524	−5.25	2.30e−07***
sw3 vs sw1	−1.33268	0.09018	469.982	−14.78	< 2e−16 ***
(4) Effect of the number of months since parturition on E1C concentrations during MS
Unit: each 1-month period from parturition
Formula: log (median E1C concentration) ~ months from parturition + months from parturition squared + (1|female ID)
	Estimate	Std. Error	df	t value	Pr( >|t|)
(Intercept)	2.22171	0.09914	28	22.41	< 2e−16 ***
Months from parturition	0.29557	0.10081	28	2.932	0.00664 **
Months from parturition squared	−0.0757	0.10081	28	−0.751	0.45892