Overall, 251 (67.5%) of the children peeked at the toy. Preliminary analyses were conducted to
examine whether there were any significant differences in peeking behavior across conditions. For this
and subsequent logistic regression analyses, the independent variables (age in months, appeal, and
punishment) and the Appeal Punishment interaction were entered first as predictors for theoretical
reasons (Menard, 2002). Additional predictors (i.e., interactions) were added individually to the model
to determine whether they would contribute significantly to the model. The method employed to
enter the predictors was the standard method on one step (Tabachnick & Fidell, 2013). Significance
was assessed by a block chi-square test (also known as the chi-square difference test). In this test,
the retention of each predictor in a model must increase the variability substantially in order to justify
using a more complex model