[bwilson4web]

Hi,

Working with the National Highway Traffic Safety Administration (NHTSA) database, the Fatality Accident Reporting System (FARS) and excel, I've figured out how to analyze the data to extract detailed records. For example, in 2007, there were these known accidents involving pedestrians and Prius:

ST	mm/dd/yyyy	Vehicles	Prius Model
CA	1/5/2007	1	2004
CA	1/24/2007	1	2006
FL	1/26/2007	1	2007
FL	9/12/2007	3	2006
TX	10/18/2007	2	2005
AZ	10/21/2007	2	2005

There were 5,432 records in the accident file giving a raw rate of 0.11% of all pedestrian accidents involved a Prius. In this rough report, there were three accidents involving more than one vehicle and pedestrian. A more rigorous analysis would take just the single vehicle pedestrian accidents.

GET THE ACCIDENT DATA

1. Start with NHTSA Encyclopedia
2. Click on "FARS FTP" link at the top
3. Select the directory for the year of interest
4. Download the ZIP file of the data
5. Open file into a drectory

You should now see a list of files:

ACCIDENT.DBF
miacc.DBF
midrvacc.DBF
miper.DBF
person.DBF
vehicle.DBF
vehnit.DBF

DATA ANALYSIS

If you have DBase or Microsoft Access, these files should load fine and you can begin to analyze the data. However, I have a Macintosh and the built-in databases were unable to do anything with these files.

In my case, a Macintosh with excel, which will "Open" any DBF file and each will load fully except for "person.DBF", which is too large to fit in one spreadsheet. But I only needed:

ACCIDENT.DBF - all accidents for the year
vehicle.DBF - all vehicles

The first row will have the name of each field per column and each subsequent row has the values. Since it loads them as text and floating point numbers even though there are no floating point fields, I select the spreadsheet and format all numbers without any fractions.

"ACCIDENT.DBF"

This file lists each accident for the year including a column for "PED", pedestrians. So I simply deleted all non-pedestrian accidents and found 5,452 records. A stricter file would just records with one pedestrian and one vehicle, ignoring the multi-vehicle accidents that also involve a pedestrian. Now this file does not include vehicle information but it does include "ST_CASE" (state case number) that is a universal index in all of the files.

"vehicle.DBF"

This file lists all vehicles involved in an accident and has a column for "ST_CASE" but in the wrong location. I make a copy of that column and do an 'insert paste' into the first column of the "vehicle.DBF" file. This will be the key needed to lookup each vehicle. But you will also need a number for each column. Going to the bottom of the spreadsheet, I add another row that is a counter for each column with the "A" column being "1."

Adding Vehicle Information To ACCIDENT.DBF Columns

Select a column in "ACCIDENT.DBF" and insert the function "vlookup". This function needs:

ST_CASE cell - using an absolute reference for the column and relative row, identify the cell with the state case number.
vehicle.DBF table - using just the data fields, not the title row nor column count row, identify the whole spreadsheet data as a table. On a Mac, I click on the upper left data cell and then SHIFT-click on the lower right.
vehicle field "MAKE_MOD" - this field includes both the manufacturer and the last thee digits are the model number. The number 49046 is the Toyota Prius.
Add as many additional vehicle fields as desired in additional columns.

UNDERSTANDING THE DATA FIELDS

Using Google, find a copy of "Analytic Reference Guide 1975 to 2006" (FARS06.pdf) for a text description of the data fields.

WHAT TO DO NEXT?

It would be great if we could find a gas-only vehicle with known sales figures and a similar sales pattern to the Prius to compare and contrast. For example, the Scion and Prius might give some insights if one or the other shows an abnormally high rate of pedestrian accidents versus their sales numbers. Anyone interested in helping with say the Scion sales figures?

Comments?
Questions?
Suggestions?

Bob Wilson

ps. I wrote a quick "c" hack to pass through the "person.DBF" file and generate a comma delimited, text file. The tricky part was dealing with the binary 'endian' but once solved, it works well enough. This is not a 'general purpose' DBase file program, no run-time arguments, everything is hard-coded as needed to get the data. But if you have an interest, send me a PM and I'll forward the source.

[bwilson4web]

Looking at the 2007 accident data, the NHTSA report DOT HS 810 993 covering 2007 fatal accidents, and the Prius sales history, I did a 'back of the envelope' analysis to compare "miles per pedestrian deaths" for all vehicles and the Prius:

• 554,000,000 miles per pedestrian death, all vehicles (~4,700 NHTSA)
• 1,023,000,000 miles per pedestrian death, Prius (~7 deaths)

Now there are a lot of variables that are not accounted for such as vehicle weight (lighter ones are less deadly,) speed (urban vs rural), and other factors. Also, we are looking at very small numbers of deaths, 7 associated with the 6 Prius pedestrian accidents. But I wanted to look at a worst case scenario. What is the worst case rate of Prius-pedestrian accidents.

The model I used started with the Prius sales per year minus 5% loss per year and 15,000 miles per vehicle per year:

Year	Sales	Running in 2007	miles/year
2000	5,562	3,884	58,260,000
2001	15,556	11,435	171,525,000
2002	20,119	15,567	233,505,000
2003	24,627	20,058	300,870,000
2004	53,991	46,290	694,350,000
2005	107,897	97,377	1,460,655,000
2006	106,971	101,622	1,524,330,000
2007	181,221	181,221	2,718,315,000

477,000 Prius on USA roads in 2007
7,162,000,000 Prius vehicle miles in 2007
6 pedestrian-Prius accidents in 2007
7 pedestrians in the accidents (actual pedestrian fatalities may be less)

1,023,116,000 miles per Prius vehicle per pedestrian deaths in 2007 (approximate)

1.64 fatalities per 100 million vehicle miles in 2007 (NHTSA report DOT HS 810 993)
60,975,610 miles per all vehicles per fatality in 2007
11% the number of pedestrian deaths of all fatalities

554,324,000 miles per all vehicle miles in 2007

This 'back of the envelope' data can not be used as an exact metric of relative risk. Variables such as vehicle weight, urban vs. rural, and other aspects have not been factored. A proper multi-variable analysis is what the National Highway Traffic Safety Administration should do. But based upon these and Dr. Christopher Hogan's 2008 report, the Prius appears to have no detectable, higher risk to pedestrians.

Bob Wilson

[centrider]

bwilson4web said:

Looking at the 2007 accident data, the NHTSA report DOT HS 810 993 covering 2007 fatal accidents, and the Prius sales history, I did a 'back of the envelope' analysis to compare "miles per pedestrian deaths" for all vehicles and the Prius:

• 554,000,000 miles per pedestrian death, all vehicles (~4,700 NHTSA)
• 1,023,000,000 miles per pedestrian death, Prius (~7 deaths)

Now there are a lot of variables that are not accounted for such as vehicle weight (lighter ones are less deadly,) speed (urban vs rural), and other factors. Also, we are looking at very small numbers of deaths, 7 associated with the 6 Prius pedestrian accidents. But I wanted to look at a worst case scenario. What is the worst case rate of Prius-pedestrian accidents.

The model I used started with the Prius sales per year minus 5% loss per year and 15,000 miles per vehicle per year:

Year Sales Running in 2007 miles/year
2000 5,562 3,884 58,260,000
2001 15,556 11,435 171,525,000
2002 20,119 15,567 233,505,000
2003 24,627 20,058 300,870,000
2004 53,991 46,290 694,350,000
2005 107,897 97,377 1,460,655,000
2006 106,971 101,622 1,524,330,000
2007 181,221 181,221 2,718,315,000

477,000 Prius on USA roads in 2007
7,162,000,000 Prius vehicle miles in 2007
6 pedestrian-Prius accidents in 2007
7 pedestrians in the accidents (actual pedestrian fatalities may be less)

1,023,116,000 miles per Prius vehicle per pedestrian deaths in 2007 (approximate)

1.64 fatalities per 100 million vehicle miles in 2007 (NHTSA report DOT HS 810 993)
60,975,610 miles per all vehicles per fatality in 2007
11% the number of pedestrian deaths of all fatalities

554,324,000 miles per all vehicle miles in 2007

This 'back of the envelope' data can not be used as an exact metric of relative risk. Variables such as vehicle weight, urban vs. rural, and other aspects have not been factored. A proper multi-variable analysis is what the National Highway Traffic Safety Administration should do. But based upon these and Dr. Christopher Hogan's 2008 report, the Prius appears to have no detectable, higher risk to pedestrians.

Bob Wilson

Well, I'm convinced, but what about Congress?

[bwilson4web]

centrider said:

Well, I'm convinced, but what about Congress?

BAD NEWS

• 117 co-sponsors in the House
• S.841 Senate bill
• Automotive Alliance support
• National Federation of the Blind meeting in Detroit
• Lotus deep pockets (GM and Chrysler probably dried up)

GOOD NEWS

• No evidence of a hybrid risk and there is enough data
• Only 4 co-sponsors on Subcommittee
• NHTSA made no reference to nonsense
• No other witnesses in the recent hearings made reference to noise makers in their testimony
• Effective accident avoidance systems received significant references in testimony
• June 23, 2008 hearing record
• Little support, less than 30%, in comments to pro-legislation articles

There are two efforts we need to focus on:

1. Get the facts and data out - a good web page is a start
2. Get the facts and data in front of our representatives

Bob Wilson

[centrider]

This is from AARP, Bob:

Our nation's transportation infrastructure is broken and needs to be fixed. Between 1993 and 2003, nearly 52,000 pedestrians and more than 7,400 bicyclists were killed in road accidents; studies show that designing streets with pedestrians in mind may reduce pedestrian risk by as much as 28 percent.
Unfortunately, among the people most hurt by inadequate roads and transportation choices are older Americans. The mobility of many older Americans is undermined by crosswalks that are too long, communities without sidewalks, and bus stops that are too dangerous to approach on foot. A recent AARP poll found that 47 percent of Americans over age 50 said they could not safely cross main roads near their homes. Almost 40 percent said their neighborhoods do not have adequate sidewalks, while another 55 percent reported no bike lanes or paths, and 48 percent reported no comfortable place to wait for the bus. In 2005, older Americans made up 20 percent of all pedestrian fatalities.



http://www.aarp.org/makeadifference/...reets_act.html

[centrider]

bwilson4web said:

BAD NEWS

• 117 co-sponsors in the House
• S.841 Senate bill
• Automotive Alliance support
• National Federation of the Blind meeting in Detroit
• Lotus deep pockets (GM and Chrysler probably dried up)

GOOD NEWS

• No evidence of a hybrid risk and there is enough data
• Only 4 co-sponsors on Subcommittee
• NHTSA made no reference to nonsense
• No other witnesses in the recent hearings made reference to noise makers in their testimony
• Effective accident avoidance systems received significant references in testimony
• June 23, 2008 hearing record
• Little support, less than 30%, in comments to pro-legislation articles

There are two efforts we need to focus on:

1. Get the facts and data out - a good web page is a start
2. Get the facts and data in front of our representatives

Bob Wilson

Here's the latest shot fired across your bow, so to speak:

www.washingtonpost.com/wp-dyn/content/article/2009/09/22/AR2009092204290.html?wpisrc=newsletter

It seems there's some confusion over what sound would, well, sound off.

It occurred to me, growing up in Chicago we lived on a street-car line. Electric, pretty quiet except for the sound of the wheels on the tracks. Or even better, because it's still running: The Chicago South Bend and South Shore RR. All electric.

But I digress. Back to that street-car. Think: The Trolley Song from the 1944 movie, Meet Me in St. Louis. Judy Garland sang, if my memory serves me, " Ding, Ding Ding . . ."

[FastMover]

I don't care what sound they pick. I am still gonna use a big brass locomotive bell, or at the very least a recording of one.

The whole thing is a case of a group of malvalent, misinformed individuals and organizations with an agenda leading the ignorant and uninformed.

RFB

[centrider]

FastMover said:

I don't care what sound they pick. I am still gonna use a big brass locomotive bell, or at the very least a recording of one.

The whole thing is a case of a group of malvalent, misinformed individuals and organizations with an agenda leading the ignorant and uninformed.

RFB

You know, I think we're on to something here - kinda like picking your own ring-sound on your cell phone. Pick your own silent car noise maker. Think of the cacophaney of traffic noise.

What fun.

[bwilson4web]

I just scanned the comments and the ratio against this is much, much higher than for it. In short, it is getting no popular support ... none worth having.

Bob Wilson

[centrider]

bwilson4web said:

I just scanned the comments and the ratio against this is much, much higher than for it. In short, it is getting no popular support ... none worth having.

Bob Wilson

Things, Bob, are not always what they appear to be. I think Judy Garland singing, "Ding, ding, ding. . ." is a pleasant way to alert people whom I am about to run down in my Prius. I mean just, "Ding, ding, ding".