Table 2 Predictors of donation decisions within Switchers.
Variable nameAdditional information variableParameter estimatesInterpretation of effect
Age0.005**The older, the more likely to donate
GenderReference group, male−0.03No effect of gender
Political orientationReference group, liberal
Conservative−0.16**Conservative voters less likely to
donate than liberal voters
Won’t tell−0.13Donation likelihood of won’t-tellers
not significantly different from liberal voters
Donationt−1Donated at t − 1 (0 = no; 1 = yes)0.96***When donated last time, one is
more likely to donate now
Donation first observationDonated at first observation
(0 = no; 1 = yes)		0.79***When donated first time in observation period,
one is more likely to donate now
CompNegDiffTests effects of negative difference in number
of questions when not donated last time
(0 = equal number of questions;
1 = substantially less questions
at t than at t − 1)		0.40***When number of questions is substantially
lower now than last time, one is
more likely to donate than if the
number of questions is equal
CompPosDiffTests effects of positive difference in number
of questions when not donated last time
(0 = equal number of questions;
1 = substantially more questions
at t than at t − 1)		0.12**When number of questions substantially
larger now than last time one is
more likely to donate than if number
of questions is equal
Donationt−1* CompNegDiffTests difference of effect CompNegDiff
when donated last time		−0.48***If donated last time, positive impact of
CompNegDiff gets “neutralized”
(0.40 + −0.48 = −0.08†)
Donationt−1* CompPosDiffTests difference of effect CompPosDiff
when donated last time		−0.30***If donated last time, positive impact of
CompPosDiff becomes negative
(0.12 + −0.30 = −0.18‡)
ConstantConstant−1.24***
σ2Variance component of the randomized intercept0.59

*P < 0.05

**P < 0.01

***P < 0.001

†This parameter estimate of −0.08 was not significant (P = 0.210).

‡This parameter estimate of −0.18 was significant (P = 0.002).