
Parameters varied across strains


Accuracy

θ and δ

Only θ

Only δ

None

Number of free parameters (k)

7

5

5

3

ΔAICc

0.5

0

45.8

65.1

Precision

w and c

Only w

Only c

None

Number of free parameters (k)

7

5

5

3

ΔAICc

7.5

0

24.7

23.7

 Note. AICc for each model was calculated as AICc (model) = 2k + n ln(RSS/n) + [2k (k + 1)/(n  k  1)], where k is the number of free parameters (3 strains × parameters varied + parameters not varied + 1 variance parameter) and n is the total number of observations (18 rats × 8 target times  16 empty cells = 128). ΔAICc is the difference between AICc of each model and AICc of the selected model; ΔAICc of the selected model is, thus, zero. Some models with lower indices were not selected because they did not improve the account by at least 10 points.