Speed reduction effects over distance of animal-vehicle collision countermeasures – a driving simulator study

European Transport Research Review

An Open Access Journal

Table 1 Results of two MARS analyses (with interactions or as an additive model without interactions) on three datasets: automatic speed camera, radio and warning sign

Dataset	Automatic speed camera		Radio		Warning sign
MARS model	With interactions	Additive model	With interactions	Additive model	With interactions	Additive model
Terms selected	32 of 32	26 of 26	37 of 37	24 of 24	29 of 29	25 of 25
Selected predictors	5 of 605	4 of 605	4 of 605	4 of 605	5 of 405	4 of 405
GCV	29.85	31	36.2	44.5	24.87	25.7
R²	0.61	0.6	0.68	0.61	0.7	0.69

Speed data includes distances according to Fig. 2. Dependent variable: vehicle speed. Independent variables: participants, AVC countermeasure (automatic speed camera, radio, and warning sign coded as dummy variables), wildlife fence, forest/open and measure point (when the countermeasure/event was encountered). GCV = generalized cross validation of the model and summed over all responses. R² = R-Squared of the model calculated over all responses. Bold typed GCV shows the lowest values and the chosen MARS model for each dataset