Table 4.

Estimated trend and variance parameters

Estimated estimated trend and variance parameters
Group	Experimental phase	${ĉ}_0$	${ĉ}_1$	${\widehat{\sigma }}_{day1}^2$	${\widehat{\sigma }}_{day2}^2$	${\widehat{\sigma }}_{night}^2$
E2	P1	29.53 ± 1.68	(0.31 ± 1.99) · 10-4	9.87 ± 3.69	4.06 ± 1.28	10.39 ± 2.76
	P2	30.35 ± 1.12	(1.37 ± 1.39) · 10-4	9.56 ± 3.25	4.91 ± 3.55	11.17 ± 2.40
	P3	30.71 ± 0.74	(-1.46 ± 0.62) · 10-4	10.22 ± 3.71	3.55 ± 0.90	9.75 ± 2.07
Tibolone	P1	30.02 ± 1.01	(1.14 ± 2.85) · 10-4	9.83 ± 2.78	5.25 ± 1.79	15.07 ± 5.24
	P2	30.23 ± 1.86	(1.53 ± 2.58) · 10-4	10.78 ± 2.51	5.85 ± 1.33	11.97 ± 2.74
	P3	30.86 ± 1.28	(-3.15 ± 1.15) · 10-4	14.77 ± 3.50	4.57 ± 1.34	11.28 ± 2.68

Mean values and standard deviations of the trend and variance parameters estimated for the E2 and the Tibolone group (sample size: 10 animals per group). ${ĉ}_0$: intercept, ${ĉ}_1$: slope, ${\widehat{\sigma }}_{day1}^2$: variance of first daytime period (6-12 a.m.), ${\widehat{\sigma }}_{day2}^2$: variance of second daytime period (12 a.m.- 6 p.m.), ${\widehat{\sigma }}_{night}^2$: variance of nighttime period (6 p.m. - 6 a.m.).