1. euroFOT: constrains and trade-offs in
testing hypotheses
SP2 – In-vehicle Systems for Driving Support
CHALMERS
Marco Dozza
Chalmers University of Technology
TRA Brussels, 8th June 2010
www.eurofot-ip.eu
Contents
• This talk in the FESTA context
• Hypotheses
• Constraints for hypotheses testing
Results
• Conclusions
www.eurofot-ip.eu

2. FESTA
Function identification Socio-economic
and description Impact Assessment
System and Function
Use cases Analysis
Research Questions Research Question and
and Hypotheses Hypothesis Analysis
Performance Study Ethical
Data Analysis
indicators Design legal issues
Data base
Measures and
Performance
Sensors Measures
indicators
Data Acquisition
www.eurofot-ip.eu
A FESTA hypothesis:
• is a statement testable with statistics
• tests a cause-effect relation
• requires:
A system (cause)
A performance indicator (effect)
A direction of change (relation)
• often requires a comparison between
baseline and treatment data
cause relation effect
• Eg. ACC decreases mean speed
www.eurofot-ip.eu

3. Data analysis:
Percentage %
www.eurofot-ip.eu
Constraints for hypothesis testing
• measurability of IVS operation
• calculability of performance indicators
• OEM-specific IVSs implementations
• risk of benchmarking
• combinations of IVSs
• baseline definition
• IVSs abuse and misuse
• nature of data collected
• access to proprietary information
• computational time
• measurability of confounding factors
• statistical significance
• reliability of maps and accident databases.
www.eurofot-ip.eu

4. ACC decreases mean speed
• ACC is one function, but implemented in 5
different systems.
www.eurofot-ip.eu
ACC decreases mean speed
• ACC is not an “on-off” function.
• ACC can be:
• On with target
• Off
• On without target (CC)
• Stand-by
• Overridden
www.eurofot-ip.eu

5. ACC decreases mean speed
• ACC may not be the only system active.
• Data can be filtered by ACC activation but
longitudinal effects cannot be related to a
single cause.
• Is it really fair to evaluate functions
individually?
• Can the experimental protocol really solve
this issue?
www.eurofot-ip.eu
ACC decreases mean speed
• What is baseline?
System off
System not available
A segment of data in which all variables
are the same but the systems status
www.eurofot-ip.eu

6. Constraints for hypothesis testing
• measurability of IVS operation
• calculability of performance indicators
• OEM-specific IVSs implementations
• risk of benchmarking
• combinations of IVSs
• baseline definition
• IVSs abuse and misuse
• nature of data collected
• access to proprietary information
• computational time
• measurability of confounding factors
• statistical significance
• reliability of maps and accident databases.
www.eurofot-ip.eu
Thanks for attention!
www.eurofot-ip.eu