http://www.cnn.com/2003/TRAVEL/11/24/speed/index.html

Speed Kills! and Indirectly More Horsepower = more deaths!

Bullsh*t!!

Apparently some guy did a study that concluded that higher speed equals more deaths on the road. Cited that in 1974 when speed limit was 55 mph that the deaths were lower. Well was the U.S. in an oil crisis during that time? Wouldn't that mean less cars on the road which means less likelihood of accidents to occur?

Problems with their arguements:
1) Horsepower does not equal to higher speed. Horsepower will gets you to speed faster.
2) 1974 probably had less cars on road for two reasons, 1. oil crisis and 2. the population of the U.S. was smaller than today so less people on the road! Of course there will be less accident deaths than today! Heck why compare auto accident deaths of today with those in 1922. Sh*t 20000% increase, sound the alarm, lower the HPs in cars, lower the speed limit to 45 mph.
3) Did study on big cities. Aren't there more people driving in big cities like Atlanta? That city also has a reputation of having the worst traffic in the U.S.
4) If speed kills then why does the Autobahn have less accidents than the US. They have practically no speed limits.
5) Montana has much higher speed limits than rest of the country but have fewer accidents. Why? Less people on the road. Again more people on the road equal more chances for auto accident fatality to occur.


If these guys have their way, you can kiss any future RX-8 or STi or M3, etc. goodbye. They even linked horsepower to accidental deaths!!!

This is another example of some scientist that didn't do experiments to determine actual reason for auto accident deaths, but relied on find correlations in existing data to determine cause. Bad use of statistics.

Sorry I had to vent. These guys piss me off. They should stick to crash tests.


Magic8

I agree completely. Its such a relative statistic, and yet they're presenting it as some absolute. Crapola if you ask me!

How are accidents in Montana? or the Desert (Nevada/Arizona)?
No speed limits in the former :p

yeah, we had the same stupid scare here in Vancouver last year during a news-slump, and the focus was on teenage asian kids killing themselves and their friends in street racing: no more or less, really, than has been going on for years, but about came the public outcry for less powerful cars!!

jesus christ, i fucking hate these idiots who don't know the first thing about cars proclaiming their solution to the world's traffic problems: how about we start with the basics, like morons driving in the left lane????

I speed constantly and was once a race driver and am an engineer.

Higher speed does = more deaths/injuries. If you don't believe speed kills then you cannot possibly have any grasp of laws of physics. Why the hell do racing series spend so much effort trying to reduce speeds? To improve safety.

Oh, and the Autobahn stuff is a myth. Their unlimited speed areas are in BFE and they do have a high rate of deaths/km driven. I have driven all of Germany and there are precious few areas within the cities that have speed limits that even approach what is in the USA.

Originally posted by babylou

Higher speed does = more deaths/injuries. If you don't believe speed kills then you cannot possibly have any grasp of laws of physics. Why the hell do racing series spend so much effort trying to reduce speeds? To improve safety.




I must agree that Higher Speed can lead to more deaths/injuries.

However, on the topic of more HP=more Deaths....I must disagree. More HP does not directly = more speed, therefore I agree that this "Study" was crazy, and was probably another waste of our tax dollars.
I have seen Honda CRXs...mostly stock....driving 110+ mph....is this study trying to to tell me that CRXs have high HP cause some idiot is driving it 110+ mph on a freeway???

Dave

The question here is does speed cause increase rate of auto accident fatality?

If you have one car on the road driving 100mph, will you be more likely to getting into a fatal accident then driving on the same road driving 50 mph with 100 cars on it. Which factor, speed or cars on the road, is the cause of the increase in likelihood of fatal accident? If speed is sole contributor to my likelihood to get into a fatal accident, then in scenario 1 I have a better chance of dying than scenario 2. But that does not make logical sense.


I too am an engineer (Mechanical), so I am well aware of physics. These guys try to link HP to accidental fatality. HP is used in acceleration and giving high top speed. If you ever calculate the loads require to maintain a constant speed, like 80mph, using the Road-Load-Power Equations, it doesn't take much HP. However if you want to get to 60 in 4.0 seconds from 0, then you need alot of HP. You also need alot of HP for high Top Speed, to overcome drag.

My points is HP doesn't cause auto death. Speed does not increase likelihood of auto accident deaths. There are other factors that they don't point out.

Yes the faster you travel, the more damage you receive when have during a crash (Conservation of Momentum and Energy.) However there is a point where damage is practically the same. (A 60mph crash into wall kills me the same as a crash into a wall at 120mph.) Then you move into the realm of likelihood. If you don't get into an accident, you won't get maimed or killed. These guys are arguing that speed INCREASES THE LIKELIHOOD for accidents to occur, not the amount of damage. Speed alone will not cause the increase in likelihood of fatal auto accidents.


I am also experienced in statistics and one of most important tenants in statistics is that "Just because you have correlation does not mean you have causation." These guys found a correlation, but it does not mean it's the cause. They didn't even produced their own data, they went data mining and massage it to conclude what they wanted to conclude. They are biased and already had a cause for fatal accidents in mind (speed and HP) and went looking for a correlation to support their claim. Where are the other factors like population growth or population density??


I willing to bet that I can find a strong correlation between US population growth (or density) and number of fatal auto accidents.



Magic8

Whether the premise is true or not, these arguments are ALWAYS a failure be cause they are post hoc, a logical fallacy.
Few of the hawkish in the news buisness EVER follow rules of logic in their arguments (goes the same for most on internet forums as well, I'm afraid) and will postulate things on statistics that are not relevant in the vacuum in which they are usually presented. In this, Magic8 is spot-on.

Babylou - you need to review the "autobahn" stats a bit so that you can compare apples to apples.

Originally posted by Maniac
Babylou - you need to review the "autobahn" stats a bit so that you can compare apples to apples.

How about you post or link some comparative data for all of us.

Originally posted by Magic8
The question here is does speed cause increase rate of auto accident fatality?

.....Speed does not increase likelihood of auto accident deaths. There are other factors that they don't point out.

.....Speed alone will not cause the increase in likelihood of fatal auto accidents.


Magic8

Give me a break! More speed means less reaction time, less vehicular control and increased impact forces. Increased speed does lead to more accidents. In all my years I have yet to see someone tag the wall at Indy on their warm up lap for qualifying.

I wondered how long it would take them to get to this. I am (not as much now as I used to be) a competitive shooter in both handgun and long, really long range rifle. I load my own ammunition, built my own very-accurate target rifle, and have been around firearms all my life.

Their argument reminds me of the magazine capacity argument that the gun-control advocates were spouting. By their logic, if I am limited to 10 shots of 9mm instead of 15 per magazine then I will likely give up my career as a drug dealer and attend medical school or something. We used to joke and say, "gosh the speed limit is 55 why does anyone need a car that does more than that?"

I never thought that speed causes accidents, injuries, deaths.

*Inappropriate* speed does.

If everyone goes about the same speed with enough distance, that can be safe at any speed.

If the majority slugs away at 55 and some idiot fails to slalom through at 75, then speed did cause an accident.
(The folks going 55 in a 65 zone caused the accident.. j/k)

This summer a guy in Germany drove a Mercedes C600 .. that super car that puts out 500hp.. he pulled up with ~150 mph behind a woman doing the max her car could = 100 mph or so.
He didn't touch her, but she got so scared that she lost control of her car, she and her kid died on the spot.
The driver didn't stop but could be identified and was found guilty.

Speed does kill, but it's inappropriate speed, be it relative to the driving conditions or to other vehicles.

I think they should have a max speed limit, but also a min speed.

E.g...left lane = min 75, max 85 mph... ideally this should be computer controlled, so that the numbers can be adapted with traffic density. I've seen such electronic speed limits that adapt to traffic 10 years ago already, so it's nothing new.

Cars with a lot of hp aren't the only problem. I don't violate the speed limit excessively, nearly always 10mph above the limit (mostly 65 on highways), but I often get passed by econo-boxes going at least 80mph. As a comparison, which car is safer driving at 80mph, a Geo Metro with poor handling and braking capability or an RX-8 with excellent handling and brakes? I think you know the answer.

The reason people like the huge hp numbers is acceleration. For everyday driving at reasonable speeds (up to 80mph), even a Geo Metro will be able to attain that if you're patient enough to wait the entire 1/2 hour. More precisely, you want to be able to quickly pass those slow pokes, which means acceleration.

How about the effect of hp as a safety feature? For example, when some car is changing lanes right into you, you can simply press the accelerator harder to avoid collision instead of moving your foot to the brake (which takes longer).

Overall, higher powered cars (in stock form) generally have better safety equipment and are built to handle extreme driving conditions, so they are better at avoiding accidents as well as minimizing passenger damage when an accident happens.

Originally posted by Magic8
http://www.cnn.com/2003/TRAVEL/11/24/speed/index.html

Speed Kills! and Indirectly More Horsepower = more deaths!

Bullsh*t!!

Apparently some guy did a study that concluded that higher speed equals more deaths on the road. Cited that in 1974 when speed limit was 55 mph that the deaths were lower. Well was the U.S. in an oil crisis during that time? Wouldn't that mean less cars on the road which means less likelihood of accidents to occur?

Problems with their arguements:
1) Horsepower does not equal to higher speed. Horsepower will gets you to speed faster.
2) 1974 probably had less cars on road for two reasons, 1. oil crisis and 2. the population of the U.S. was smaller than today so less people on the road! Of course there will be less accident deaths than today! Heck why compare auto accident deaths of today with those in 1922. Sh*t 20000% increase, sound the alarm, lower the HPs in cars, lower the speed limit to 45 mph.
3) Did study on big cities. Aren't there more people driving in big cities like Atlanta? That city also has a reputation of having the worst traffic in the U.S.
4) If speed kills then why does the Autobahn have less accidents than the US. They have practically no speed limits.
5) Montana has much higher speed limits than rest of the country but have fewer accidents. Why? Less people on the road. Again more people on the road equal more chances for auto accident fatality to occur.


If these guys have their way, you can kiss any future RX-8 or STi or M3, etc. goodbye. They even linked horsepower to accidental deaths!!!

This is another example of some scientist that didn't do experiments to determine actual reason for auto accident deaths, but relied on find correlations in existing data to determine cause. Bad use of statistics.

Sorry I had to vent. These guys piss me off. They should stick to crash tests.


Magic8

Heh...1974 also equates to LESS SUV'S!!!

Ya, that's right SUV's. I'm sure there are a lot of responsible SUV owners and all, but here in Santa Barbara and SoCal for the hell of it, there are too many egotistical people driving in a massive SUV by themselves, phone in one hand, starbuck's coffee in the other. They go 85+ on the freeway on the freaking London Two-story bus of a vehicle and rely only upon their side mirrors before merging into other lanes, hell, have the time, they don't even use the side mirrors!

But hey...our peppy little sports cars that are built to properly handle higher speeds safer are too dangerous because they have more horsepower than most cars of it's size...RIGHT...

again, i'll state that speed doesn't cause accidents, and that bad drivers do.

people causing aggrivation to other drivers, people driving dangerously or inattentively, people who don't maintain their car properly (driving on innapropriate or dangerous tyres, poorly aimed mirrors, non-functioning lights, etc).

i'll not contend with lou's point that speed makes it more dangerous in an accident, but how many times have you seen an accident, with no flips, no outrageous speeds, with people extremely injured or dead?? i have, quite a few times. 80kph, with just the wrong amount of factors helping out, can tear a little car to bits.

my ideal speed on the freeway is about 120kph, but don't think for a second that i tear through traffic, changing lanes like a maniac; on the contrary, i know that i am the most able, safest, and most conciencious driver in my family (none of my younger brothers drive yet, not that it would matter). being aware of road conditions, the limits of your tyres (the speed rating, i mean; mine go to 160 kph), how to control the car properly (braking being one of the biggest facets), using lanes properly, respecting other vehicle's right of way, etc etc etc.

it's the people that talk on their celphones, the people that stear with one hand on the bottom of the wheel resting between their thighs while they look out the side window and smoke, that fool around with their kids in the back seat, that simply try to be insulated from the experience of driving and don't pay close attention.

speed doesn't help anything, safety-wise, but crashes are caused by bad driving.

Speed alone does not cause accidents, but it is a factor. Higher speeds in a crash DO cause more deaths - that is for certain. Even if the stats they used in the article were accurate, my question is: so what? Why is it a bad thing that more people are getting killed on the roadways? We've failed to police ourselves and now the planet is seriously overpopulated. Something's gotta give.

Speed doesn't kill, inattentive drivers in poorly maintained vehicles do.

Keep right, pass left. Implement heinously difficult licensing standards. Make it costly. Make sure people know how to handle a skid, emergency maneuvers.. braking. Not this candyass "stop before the line" and "park in this stall" kinda of drivers testing we have now.

If I'm on the highway, my number one goal is to get through traffic as quickly and safely as possible, because I simply don't want to trust my safety to some barely qualified dolt who can't even stay in his own lane. I am far safer speeding off by myself at 85-90 then I would be huddled in a pack of cars doing 60-65. :)

So close to the Holidays....well let's just say work is not productive right now.

I went to the National Center for Statistics and Analysis (NCSA) of the NHTSA and grabbed their report on Accidents in 2002. It's a 220 pages of analysis and data.

Here is their data for Fatalities in relations to Speed Limit. Refer to page 67 of the report.

30mph or less....................... 3,784 deaths
35mph or 40mph................... 6,555 deaths
45mph or 50mph................... 6,975 deaths
55mph................................... 12,209 deaths
60mph or more...................... 7,569 deaths
No Satuatory Limits............... 99 deaths
Unknown............................... 1,118 deaths

The vast majority of fatalities for 2002 occurred in areas where the speed limit is 55mph or less. One conclusion you draw from this is that you should have speed limits 60mph or greater (better yet no speed limtis :)) because there is a smaller chance of auto accident fatalities to occur.

Of course there is one important factor that also needs to be examined and that is there is more areas with 55mph or less speed limits so more likelihood for accidents to occur. Nonetheless this does shoot a hole in the arguement that speed ALONE contribute to increase likelihood for fatalities to occur.


Concerning the race track example. One important that must be included and that is driver agression. In a race, the driver must be agressive to win and their sole purpose is to win. Yes they drive fast but they are also agressively jocking for positions. If they all drive 150mph without being aggressive they are less likely to get into a fatal accident (b/c they have a lower chance of getting into an accident in general.)



Magic8


If I knew how to attach files I would attach the NCSA report.

Originally posted by Magic8
So close to the Holidays....well let's just say work is not productive right now.

I went to the National Center for Statistics and Analysis (NCSA) of the NHTSA and grabbed their report on Accidents in 2002. It's a 220 pages of analysis and data.

Here is their data for Fatalities in relations to Speed Limit. Refer to page 67 of the report.

30mph or less....................... 3,784 deaths
35mph or 40mph................... 6,555 deaths
45mph or 50mph................... 6,975 deaths
55mph................................... 12,209 deaths
60mph or more...................... 7,569 deaths
No Satuatory Limits............... 99 deaths
Unknown............................... 1,118 deaths

The vast majority of fatalities for 2002 occurred in areas where the speed limit is 55mph or less. One conclusion you draw from this is that you should have speed limits 60mph or greater (better yet no speed limtis :)) because there is a smaller chance of auto accident fatalities to occur.

Magic8


...but the analysis has to be on the margin: gross account of how many accidents there were in those areas aren't of any use until you know how great the flow of traffic was in those areas, and can come up with a "rate of crash" at those (legal) speeds.

Some food for thought.

http://www.ibiblio.org/rdu/sl-irrel.html

Originally posted by revhappy
Some food for thought.

http://www.ibiblio.org/rdu/sl-irrel.html

from above:

Summary of Findings

The pertinent findings of this study, conducted to examine the effects of lowing and raising posted speed limits on nonlimited access rural and urban highways, are listed below:


* Based on the free-flow speed data collected for a 24-h period at the experimental and comparison sites in 22 States, posted speed limits were set, on the average, at the 45th percentile speed or below the average speed of traffic


* Speed limits were posted, on average, between 5 and 16 mi/h (8 and 26 km/h) below the 85th percentile speed.


Lowering speed limits by 5, 10, 15, or 20 mi/h (8, 16, 24, or 26 km/h) at the study sites had a minor effect on vehicle speeds. Posting lower speed limits does not decrease motorist's speeds.


* Raising speed limits by 5, 10, or 15 mi/h (8, 16, or 25 km/h) at the rural and urban sites had a minor effect on vehicle speeds. In other words, an increase in the posted speed limit did not create a corresponding increase in vehicle speeds.


* The average change in any of the percentile speeds at the experimental sites was less than 1.5 mi/h (2.4 m/h), regardless of whether the speed limit was raised or lowered.


* Where speed limits were lowered, an examination of speed distribution indicated the slowest drivers (1st percentile) increased their speed approximately 1 mi/h (1/6 km/h). There were no changes on the high-speed drivers (99th percentile)


* At sites where speed limits were raised, there was an increase of less than 1.5 mi/h (2.4 km/h) for drivers traveling at and below the 75th percentile speed. When the posted limits were raised by 10 and 15 mi/h (16 and 24 km/h), there was a small decrease in the 99th percentile speed.


* Raising speed limits in the region of the 85th percentile speed has an extremely beneficial effect on drivers complying with the posted speed limits.


* Lowering speed limits in the 33rd percentile speed (the average percentile that speed were posted in this study) provides a noncompliance rate of approximately 67 percent.


* After speed limits were altered at the experimental sites, less than one-half of the drivers complied with the new posed limits.


* Only minor changes in vehicles following as headways less than 2s were found at the experimental sites.


* Accidents at the 58 experimental sites where speed limits were lowered increased by 5.4 percent. The level of confidence of this estimate is 44 percent. The 95 percent confidence limits for this estimate ranges from a reduction in accidents of 11 percent to an increase of 26 percent.


* Accidents at the 41 experimental sites where speed limits were raised decreased by 6.7 percent. The level of confidence of this estimate in 59 percent. The 95 percent confidence limits for this estimate ranges from a reduction in accidents of 21 percent to an increase of 10 percent.


* Lowering speed limits more than 5 mi/h (8 km/h) below the 85th percentile speed of traffic did not reduce accidents.


* The indirect effects of speed limit changes on a sample of contiguous and adjacent roadways was found to be very small and insignificant.

Originally posted by revhappy
http://www.ibiblio.org/rdu/sl-irrel.html

and further:

Conclusion

The primary conclusion of this research is that the majority of motorist on the nonlimited access rural and urban highways examined in this study did not decrease or increase their speed as a result of either lowering or raising the posted speed limit by 4, 10, or 15 mi/h (8, 16, or 24 km/h). In other words, this nationwide study confirms the results of numerous other observational studies which found that the majority or motorist do not alter their speed to conform to speed limits they perceive as unreasonable for prevailing conditions.

*snip*

Although there are variations from State to State, on average, speed limits were posed 5 and 16 mi/h (8 and 26 km/h) below the 85th percentile speed. As all States use the 85th percentile as a major criterion for establishing safe and reasonable speed limits, it is surprising that the new speed limits posted on the experimental sections examined in this study deviated so far from the 85th percentile speed. There are several plausible reasons. Once commonly cited reason for posting unreasonably low speed limits is public and political pressure. While individuals and politicians clearly influence some speed limit decision, there are other factors involved.

http://www.ibiblio.org/rdu/figure10.gif

*snip*

The data collected during this study indicate that there are no benefits, either from a safety or operational point of view, from establishing speed limits less than the 85th percentile speed. This does not mean that all speed limits should be raised. Traffic and engineer investigations should be conducted to obtain an accurate measure of the speed distribution. Greater emphasis should be placed on using the 85th percentile speed in setting safe and reasonable speed limits. These studies should be repeated as land use and traffic characteristics change.