BTS | Table B-2 Downs Model

Bureau of Transportation Statistics (BTS) - Research and Innovative Technology Administration (RITA) - United States Department of Transportation (USDOT, US DOT or DOT)

ABOUT RITA | CONTACT US | PRESS ROOM | CAREERS | SITE MAP

Data and Statistics

Bookstore

Programs

About BTS

Upcoming Press Releases

External Links

BTS Home > Publications > Journal of Transportation and Statistics > Volume 4 Number 1 > Paper 4

Table B-2 Downs Model

Excel | CSV

	Equation
	1	2	3	4
Assumptions: Semantic differences: Cost: None-minor	1	2.6	1	1.8
Assumptions: Semantic differences: Cost: Minor-moderate	1	1.0	1	1.0
Assumptions: Semantic differences: Cost: Moderate-great	1	1.0	1	1.0
Assumptions: Component weights: Effectiveness: Extent	1	1	1.0	1.0
Assumptions: Component weights: Effectiveness: Impact	1	1	1.3	1.1
Assumptions: Component weights: Cost: Direct to commuters	1	1	1.0	1.0
Assumptions: Component weights: Cost: To all of society	1	1	2.2	1.9
Assumptions: Component weights: Implementation: Required institution	1	1	13.0	11.0
Assumptions: Component weights: Implementation: Ease of administration	1	1	1.0	1.0
Results: Estimated coefficients: Supply-side: Coefficient	0.29*	0.27*	0.43*	0.37*
Results: Estimated coefficients: Supply-side: Standard error	0.14	0.13	0.14	0.13
Results: Estimated coefficients: Supply-side: t-score	2.16	2.11	3.05	2.80
Results: Estimated coefficients: Effectiveness: Coefficient	-0.22	-0.26*	-0.33*	-0.32*
Results: Estimated coefficients: Effectiveness: Standard error	0.14	0.13	0.12	0.12
Results: Estimated coefficients: Effectiveness: t-score	-1.58	-2.01	-2.77	-2.79
Results: Estimated coefficients: Cost: Coefficient	-0.59*	-0.58*	-0.64*	-0.62*
Results: Estimated coefficients: Cost: Standard error	0.14	0.13	0.13	0.13
Results: Estimated coefficients: Cost: t-score	-4.23	-4.5	-4.79	-4.95
Results: Estimated coefficients: Implementation: Coefficient	-0.3*	-0.36*	-0.28*	-0.35*
Results: Estimated coefficients: Implementation: Standard error	0.13	0.13	0.13	0.2
Results: Estimated coefficients: Implementation: t-score	-2.3	-2.89	-2.2	-2.81
Results: Goodness-of-fit: Standard error of Y	0.61	0.59	0.56	0.55
Results: Goodness-of-fit: R-squared	69.30%	71.10%	74.50%	75.40%
Results: Goodness-of-fit: Number of observations	23	23	23	23
Results: Goodness-of-fit: Degrees of freedom	19	19	19	19

* significant at 0.01 level
** significant at 0.05 level
*** 1.00 < t < 2.00
d.f. = degrees of freedom
HOV = high-occupancy vechicle
NA = not applicable
SOV = single-occupancy vehicle
SRSD = studentized residual
TDM = travel demand management
TMA = transportation management association
TSM = transportation system management
U = data are unavailable
VHT = vehicle hours of travel
VMT = vehicle-miles traveled
* Significant at 95% confidence interval.