Table 4. AICc model selection results for 2012 for models that fell within 4 AICc of the top model.

Model	K	ΔAICc	Model weight (wi)
B. impatiens	3	0	0.53
B. impatiens, Field size	4	2.80	0.13
B. impatiens, A. mellifera	4	2.82	0.13
B. impatiens, P. pruinosa	4	3.26	0.10

Independent variables included in the model selection to predict pumpkin yield included bee visitation frequency to pumpkin flowers (Bombus impatiens, Apis mellifera and Peponapis pruinosa), supplementation treatment (B. impatiens supplemented, A. mellifera supplemented and nonsupplemented) and field size.