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. 2010 Jun 16;277(1697):3203–3212. doi: 10.1098/rspb.2010.0673

Table 1.

Results from AIC analyses for baseline corticosterone (Cort0), stress-induced corticosterone (MaxCort) and testosterone, using different datasets. The model with the highest weight (i.e. the most parsimonious model; high. model w.) for each hormonal trait and dataset is indicated, with contributing variables included in brackets, and the overall r2 for this model. Variable weights (var. weight, 0–1) are the sum of the importance values for each of the models including the independent variable (variables with high values are highlighted in bold). Raw regression coefficients (raw regr. coeff.) are given along with standardized regression coefficients (stand. regr. coeff.), the latter being normalized by the standard deviations of the observations for the dependent and independent variables.

hormonal trait Cort0
 MaxCort
 testosterone
dataset own (n = 24) own (n = 20) own (n = 9)
high. model w. 0.23 (breeding season), r2 = 0.11
 0.22 (mass and survival), r2 = 0.41
 0.74 (breeding season), r2 = 0.79
variable mass surv. breed. envt. mass surv. breed. envt. mass surv. breed. envt.
var. weight 0.27 0.28 0.48 0.44 0.79 0.53 0.42 0.38 0.08 0.08 0.97 0.11
raw regr. coeff. −0.07 −0.29 −0.06 −0.18 −0.46 1.12 −0.06 0.17 0.13 −0.74 −0.43 −0.28
stand. regr. coeff. −0.06 −0.07 −0.28 −0.26 −0.50 0.45 −0.37 0.34 0.11 −0.19 −2.03 −0.40
dataset own + published*, only mesic and tropical (n = 37) own + published*, only mesic and tropical (n = 31) own + published*, only mesic and tropical (n = 22)
high. model w. 0.16 (mass and breeding season), r2 = 0.27
 0.146 (mass and survival), r2 = 0.2
 0.2 (envt), r2 = 0.47
var. weight 0.52 0.24 0.69 0.58 0.60 0.45 0.36 0.46 0.26 0.27 0.19 0.99
raw regr. coeff. −0.31 0.04 −0.08 −0.26 −0.26 0.64 −0.03 0.14 0.26 0.96 0.001 −0.69
stand. regr. coeff. −0.24 0.01 −0.35 −0.32 −0.32 0.25 −0.23 0.29 0.14 0.16 0.00 −0.68
dataset own + published* incl. arid and cold (n = 41) own + published* incl. arid and cold (n = 35) own + published* incl. arid and cold (n = 26)
high. model w. 0.11 (breeding season), r2 = 0.29
 0.093 (mass and survival), r2 = 0.35
 0.19 (envt.), r2 = 0.51
variable
 mass
 surv.
 breed.
 trop.
 arid
 cold
 mass
 surv.
 breed.
 trop.
 arid
 cold
 mass
 surv.
 breed.
 trop.
 arid
 cold
var. weight 0.75 0.24 0.76 0.55 0.28 0.25 0.47 0.31 0.35 0.47 0.91 0.22 0.22 0.25 0.2 0.99 0.21 0.48
raw regr. coeff. −0.31 −0.15 −0.08 −0.24 −0.18 0.46 −0.27 0.76 −0.03 0.15 −0.46 −0.05 0.14 0.77 −0.01 −0.7 −0.11 0.44
stand. regr. coeff. −0.24 −0.04 −0.36 −0.29 −0.11 0.28 −0.28 0.35 −0.23 0.27 −0.55 −0.06 0.08 0.13 −0.04 −0.65 −0.06 0.26