road safety Flashcards
What is the risk of transportation?
- Accidents can happen
- Due to weather, car failure but often avoidable and due to drivers taking excessive risk
- Speeding fatigue and drunk driving
What percentage of drivers who had a crash due to drunk driving
- 40% of fatal crashes in the U in 2003, 114 bn in cost
What does research say about the main factors of accidents?
- Gray et al most involved young male drivers
- did an analysis on 54k accidents involving serious injury
- accidents often involve a male of the age 18-25
- Accidents occur on roads with higher speed limits especially on single carriage roads
- Most likely in dry conditions and weekends/night time
Whats the issue with reducing risk of accidents
- It is costly –. Lower speed means more travel time
- Expensive equipment
- Enforcement requires resources
- Trade-off: There are benefits to taking more risks (higher speed save travel time), but increases the chance of an accident
- Removing risk entirely is too costly
Draw the diagram which displays the driver choice of speed
- The curvy diagram
why is intervention needed in terms of road safety?
is there an externality
- Drivers take too much risk don’t consider all the cost the accident may cause
Why do driver fail to consider all the cost of an accident?
- Cost of the accident are partly external
- May injure themselves by can injury other drivers and pedestrians
- They underestimate risk they think they are fitter than they actually are
What are tools used to ensure that driver internalize cost of accidents
- Insurance
- Regulation
- Mandating safety devices in cars
What is the purpose of car insurance?
- Provide an effective way to cover risk associated to driving
- Make individuals internalize cost of accidents they may cause
How does car insurance work?
- Pooling risk of accidents from many drivers
- Risk of accidents are uncorrelated across drivers everyone pays a premium, since relatively few have severe accidents the premium will cover the large costs
What are the caveats of car insurance
- Moral hazard: drivers will now take more unnecessary risks since they know the insurance will pay for any damage
How does car insurance discourage drivers from taking too much risk?
- Bonus system: premium goes down every year if you do not make claims
- Pay-as-drive: pay less if you drive less
- Video recording of driving : greater control on individual behaviour
What does studies show about the effect of introduction of safety devices in the US
- Pelztsman 1947-1972
- There is no significant effect of safety devices on road accident death for car occupant
- Increase risk of injury for non occupants due to compensating behaviour
What policy did authorities do, to minimize the cost of accidents?
- Mandate the adoption of safety features in cars
- Enforce it with penalties wearing front seat belts is compulsory since 1983
What is the positive effect of safety features in cars?
- Sear belts prevent ejection from vehicle
- Reduce serious injury in an accident
Is the probability of accidents exogenous?
not exogenous they depend on the drivers behaviour:
- Driver behaviour: they speed which would proportionally affect the seriousness of the injury
- People drive faster they have a seat belt – compensating behaviour worse effect on bystanders as a result
What is compensating behaviour?
- Where the implementation of safety in cars, would compensate for the extra risk a driver would take when taking a journey
What does compensate behaviour mean for safety devices
- Suggest the overall impact on injuries could be lower if there were no compensating behaviour
What do studies state about the effect of safety devices on road accidents?
- Peltzman 1975
- Stated there is no significant effect of safety devices on road accident death for occupants
- Increase in risk of injury for non-occupants and bystanders
- Shower compensating behaviour is true
What does new studies show about safety devices?
- Cohen and Einac 2003
- Provide recent evident of the effect of safety belt
- Positive effect: reduction in injuries of driver
- No evidence of the belt usage led to an increase in injuries to non-occupants
What do old studies state about the effect of speed limits?
- Keeler 1994
- No reduction in fatalities in rural areas
- Some effect in urban areas
- Explained by Offsetting behaviour: they are more willing to take risk if they expect other driver to more careful
- Enforcement: for speed limits to survive they need to be credibly enforced
- Congestion: reduces speed and reduces the variance of speed (everyone drives at a similar speed)
What do recent studies state about the effect of speed limits
- Tang 2017
- provides evidence on the effectiveness of speed cameras reducing the number of serious accidents
- Data taken from large sample of speed camera in Great Britain
What is the idea of enforcing speed limits?
- Compare accidents along a stretch of road encompassing a camera
- Compare the effect of a camera on a road relative to a similar road with no cameras
- Called the difference-in-difference strategy allows for cameras to be on roads with higher risk of accidents
What do statistics say about the effectiveness of speed-cameras?
- Reduces the annual number of accidents by 0.42 in the 100m closest to the location of installation
- Reduce serious injuries by 20 percent
- 50% reduction in accident deaths
What does data suggest about ‘drink driving’, being a cause of crashes?
40% of car crashes in the US in 2013 was due to drunk driving
- this as a result cost the economy114bn dollars
supported by studies from the Netherlands, showing how costly it is
How effective were polices in reducing ‘drink driving’?
very effective, since introducing 400% more breath tests it leads to a 40% in drivers caught with excess alcohol in their blood.
However, when these tests were by 50%, drivers caught increased by 70%
