Table 1.

Equivalence of multilevel model and summary-statistics approaches for analysing data with equal cluster sizes.

	Dataset A	Dataset B
Nesting description	Clusters within conditions	Conditions within clusters
Multilevel model	Intensity ∼ Condition + (1 | Cluster)	Intensity ∼ Condition + (1 + Condition | Cluster)
Fixed effects (SE)
Intercept	.77 (.22) t(10) = 3.54, p = .005	.49 (.20) t(11) = 2.52, p = .028
Slope	.83 (.31) t(10) = 2.68, p = .023	.49 (.20) t(11) = 2.51, p = .029
Random effects
Intercept variance	.23	.35
Slope variance		.25
Correlation		-.01
Within cluster (residual) variance	.51	.53
Summary-statistics approach
Two sample t-test	t(10) = 2.68, p = .023
Paired samples t-test		t(11) = 2.51, p = .029