Table 21.

Results from a linear mixed effects model examining factors affecting nest sizes of blue tits (Cyanistes caeruleus) in Wytham woods, Oxfordshire. This analysis was run on a subset of data of females that bred more than once to investigate any affect their difference in lay date has on their nest size (n = 230), d.f.s were calculated from Satterthwaite approximations. This model had an R² of 0.013.

parameter	estimate ± s.e.	d.f.	T-value	p-value
intercept	0.312 ± 0.019	6.510	16.124	1.73 × 10−6
change in lay date	−0.126 ± 0.007	115.800	−1.806	0.073
random effect		Chi d.f.	χ2	p-value
compartment		1	1.36 × 101	2 × 10−4
year		1	2.84 × 10−14	1