Traffic_ Why We Drive The Way We Do - Part 15
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Part 15

about to hit: See Kenneth Todd, "Traffic Control: An Exercise in Self-Defeat," Regulation Magazine, Regulation Magazine, vol. 27, no. 3 (Fall 2004). vol. 27, no. 3 (Fall 2004).

free of junctions): See "The Impact of Driver Inattention on Crash/Near-Crash Risk: An a.n.a.lysis Using the 100-Car Naturalistic Driving Study Data," DOT HS 810-594, U.S. Department of Transportation, April 2006, p. 118.

"allow it on the roads": Jake Voelcker, in his article "A Critical Review of the Legal Penalties for Drivers Who Kill Cyclists or Pedestrians," makes the useful point that "Health and Safety regulations would not permit thousands of one-tonne steel and gla.s.s machines with exposed moving parts to repeatedly pa.s.s feet or inches away from unprotected workers on the shop floor at well over 10 m/s (HSE 1998, Sect. 11). Yet this is the situation in our towns and cities today. Why are drivers allowed to impose this danger on pedestrians without more strict prosecution of liability?" Retrieved from www.jake-v.co.uk/cycling.

no posts: V. P. Kallberg, "Reflector Posts-Signs of Danger?" Transportation Research Record, Transportation Research Record, vol. 1403, pp. 5766. vol. 1403, pp. 5766.

than when it is not: See, for example, S. Comte, A. Varhelyi, and J. Santos, "The Effects of ATT and Non-ATT Systems and Treatments on Driver Speed Behaviour," Working Paper R 3.1.1 in the MASTER project, VTT Communities & Infrastructure (VTT, Finland), August 1997.

it confuses traffic people too: See Raymond A. Krammes, Kay Fitzpatrick, Joseph D. Blaschke, and Daniel B. Fambro, Speed: Understanding Design, Operating, and Posted Speed, Speed: Understanding Design, Operating, and Posted Speed, Report No. 14651 (Austin, TX: Texas Dept. of Transportation, March 1996). Report No. 14651 (Austin, TX: Texas Dept. of Transportation, March 1996).

"time-consuming effort": See David Shinar, Psychology on the Road: The Human Factor in Traffic Safety Psychology on the Road: The Human Factor in Traffic Safety (New York: Wiley, 1978), p. 87. (New York: Wiley, 1978), p. 87.

in the period studied: Neal E. Wood, "Shoulder Rumble Strips: A Method to Alert 'Drifting' Drivers," Pennsylvania Turnpike Commission, Harrisburg, Pennsylvania, January 1994.

nor is it always easy to locate: Think for a moment about when you come across a hill on a freeway. It is rarely very steep, but then again, it is not flat. Notice how the road gently unspools before you as you near the crest of the hill. The road has been designed so that if there is an unexpected obstacle lurking over that hill, the average driver should be able to see it and have enough time to react and stop. This seems like a smart idea. But how high should the imaginary obstacle be? What would make the road "safe"? Ezra Hauer, a retired Canadian professor of engineering, has observed that early on, highway engineers settled on a four-inch obstacle-a hypothetical "dead dog." They did not know whether three-inch obstacles might also be dangerous, or even how many people were hitting four-inch roadkill as they came over a hill. All they really knew was that building the road so that drivers could stop in time for a three-inch obstacle would require more excavating, and thus more money. Little decisions like this may seem trivial, but in a larger sense they literally help shape the way our world looks to us (and how people behave in it). And so for every highway on a hill in America, the road was designed so the average driver could stop in time for a four-inch "dead dog." In the absence of real information about how, why, and when obstacles on the road lead to crashes, this was, at the very least, prudent engineering, Hauer argues, based on the most efficient construction costs. But over time, something strange happened. Cars began to get lower. Suddenly, drivers could not see the four-inch obstacle in the given time. So the "dead dog" grew two inches taller-even though, Hauer says, "no link has been found between the risk of collisions with small fixed objects on crest curves and the available sight distance." New roads were built with the new standard (and on existing roads, the driver had just better pray there were no four-inch dogs lying around). Things have since gotten even more complicated. The popularity of SUVs and pickup trucks in the United States means there is "some evidence," as Ray Krammes told me, that cars are now getting higher. higher. Is it time to lower the dead dog? See Ezra Hauer, "Safety in Geometric Design Standards," Toronto, Ontario, 1999. Retrieved from Is it time to lower the dead dog? See Ezra Hauer, "Safety in Geometric Design Standards," Toronto, Ontario, 1999. Retrieved from http://ca.geocities.com/[email protected]/Pubs/SafetyinGeometricDesign.pdf.

in the United States alone): Steve Moler, "Stop. You're Going the Wrong Way!" Public Roads, Public Roads, vol. 66, no. 2 (SeptemberOctober 2002). vol. 66, no. 2 (SeptemberOctober 2002).

moving smoothly triples: triples: The literature on weaving sections is surprisingly enormous, but for a good summary of weaving-section research and dynamics, see Richard Glad, John C. Milton, and David K. Olson, The literature on weaving sections is surprisingly enormous, but for a good summary of weaving-section research and dynamics, see Richard Glad, John C. Milton, and David K. Olson, Weave a.n.a.lysis and Performance: The Washington State Case Study Weave a.n.a.lysis and Performance: The Washington State Case Study (Olympia, Wash.: 2001). (Olympia, Wash.: 2001).

safer and more efficient: See, for example, Richard W. Glad, Milton, and Olson, ibid.

be less less safe: This information comes from an unpublished paper by Ezra Hauer, "Lane Width and Safety" (review of literature for the Interactive Highway Safety Design Model, 2000); accessed at safe: This information comes from an unpublished paper by Ezra Hauer, "Lane Width and Safety" (review of literature for the Interactive Highway Safety Design Model, 2000); accessed at http://ca.geocities.com//download.htm).

not statistically significant. See Karin M. Bauer, Douglas W. Harwood, Karen R. Richard, and Warren E. Hughes, "Safety Effects of Using Narrow Lanes and Shoulder-Use Lanes to Increase the Capacity of Urban Freeways," Transportation Research Record: Journal of the Transportation Research Board, Transportation Research Record: Journal of the Transportation Research Board, vol. 1897 (2004). On a side note concerning the phrase "statistically significant," Ezra Hauer cautions that statisticians and policy makers often take the phrase "statistically not significant," when referring to a traffic-safety study, to mean there would be no cost or benefit to implementing or not implementing some policy or another. Hauer points as one example to a series of studies examining the adoption of "right turn on red" laws; all showed higher crash rates after right turn on red was adopted. None were "statistically significant," but all "pointed in the same direction": Allowing right turns on red led to more crashes. See Hauer, "The Harm Done by Tests of Significance," vol. 1897 (2004). On a side note concerning the phrase "statistically significant," Ezra Hauer cautions that statisticians and policy makers often take the phrase "statistically not significant," when referring to a traffic-safety study, to mean there would be no cost or benefit to implementing or not implementing some policy or another. Hauer points as one example to a series of studies examining the adoption of "right turn on red" laws; all showed higher crash rates after right turn on red was adopted. None were "statistically significant," but all "pointed in the same direction": Allowing right turns on red led to more crashes. See Hauer, "The Harm Done by Tests of Significance," Accident a.n.a.lysis & Prevention, Accident a.n.a.lysis & Prevention, vol. 36 (2004), pp. 495500. vol. 36 (2004), pp. 495500.

"to the road they see": See Hauer, "Lane Width and Safety," op cit.

already on the road: See Robert E. Dewar and Paul L. Olson, Human Factors in Traffic Safety Human Factors in Traffic Safety (Tucson: Lawyers and Judges Publishing, 2002), p. 429. David Shinar writes of the "double jeopardy" of misidentified signing. "Misidentified signs compromise safety by taking more time from the driving task (Tucson: Lawyers and Judges Publishing, 2002), p. 429. David Shinar writes of the "double jeopardy" of misidentified signing. "Misidentified signs compromise safety by taking more time from the driving task and and leading drivers to make incorrect decisions. But signs that are interpreted as opposite of their intended meaning mislead the drivers who seem to respond to them as quickly as they do to signs that they identify correctly. Indicating that in these infrequent cases the drivers are sure, but wrong." See Shinar, leading drivers to make incorrect decisions. But signs that are interpreted as opposite of their intended meaning mislead the drivers who seem to respond to them as quickly as they do to signs that they identify correctly. Indicating that in these infrequent cases the drivers are sure, but wrong." See Shinar, Traffic Safety and Human Behavior Traffic Safety and Human Behavior (Amsterdam: Elsevier, 2007), p. 168. (Amsterdam: Elsevier, 2007), p. 168.

not put them up: See Supplemental Advance Warning Devices: A Synthesis of Highway Practice, Supplemental Advance Warning Devices: A Synthesis of Highway Practice, National Cooperative Highway Research Program Synthesis 186 (Washington, D.C.: National Academy Press, 1993), p. 38. National Cooperative Highway Research Program Synthesis 186 (Washington, D.C.: National Academy Press, 1993), p. 38.

fewer deer had crossed: See T. M. Pojar, D. F. Reed, and T. C. Reseigh, "Effectiveness of a Lighted, Animated Deer Crossing Sign," Journal of Wildlife Management, Journal of Wildlife Management, vol. 39, no. 1 (1975), pp. 8791. vol. 39, no. 1 (1975), pp. 8791.

"deer-vehicle collision": See K. M. Gordon, S. H. Anderson, B. Gribble, and M. Johnson, "Evaluation of the FLASH (Flashing Light Animal Sensing Host) System in Nugget Canyon, Wyoming," Report No. FHWA-WY-01/03F, University of Wyoming, Wyoming Cooperative Fish and Wildlife Research Unit (Laramie, Wy.: July 2001).

MOOSE SIGNS AHEAD: The moose story comes from Robert Finch, "Moose Signs Ahead," Orion, Orion, JulyAugust 2007, p. 7. JulyAugust 2007, p. 7.

"they'll behave like that": Monderman's suspicion of traffic signs was not necessarily a radical stance. The Manual on Uniform Traffic Control Devices, The Manual on Uniform Traffic Control Devices, the bible of American traffic engineers, itself has a warning about warning signs: "The use of warning signs," it notes, "should be kept to a minimum as the unnecessary use of warning signs tends to breed disrespect for all signs." the bible of American traffic engineers, itself has a warning about warning signs: "The use of warning signs," it notes, "should be kept to a minimum as the unnecessary use of warning signs tends to breed disrespect for all signs."

is cognitive dissonance: Whether a driver actually gets gets the ticket may depend on several factors, as a study by Thomas Stratmann and Michael Makowsky argued. "The farther the residence of a driver from the munic.i.p.ality where the ticket could be contested," they wrote, "the higher is the likelihood of a speeding fine, and the larger the amount of the fine. The probability of a fine issued by a local officer is higher in towns when constraints on increasing property taxes are binding, the property tax base is lower, and the town is more dependent on revenues from tourism." From Michael Makowsky and Thomas Stratmann, "Political Economy at Any Speed: What Determines Traffic Citations?," January 31, 2007; available at the ticket may depend on several factors, as a study by Thomas Stratmann and Michael Makowsky argued. "The farther the residence of a driver from the munic.i.p.ality where the ticket could be contested," they wrote, "the higher is the likelihood of a speeding fine, and the larger the amount of the fine. The probability of a fine issued by a local officer is higher in towns when constraints on increasing property taxes are binding, the property tax base is lower, and the town is more dependent on revenues from tourism." From Michael Makowsky and Thomas Stratmann, "Political Economy at Any Speed: What Determines Traffic Citations?," January 31, 2007; available at http://ssrn.com/abstract=961967.

dawn of the car itself: According to the research of one historian, the speed b.u.mp was first introduced in Chatham, New Jersey, on April 22, 1906. As reports noted, the paved stone in the road was meant to combat "automobile scorchers," as speeders were then known. See Peter Applebome, "Making a Molehill Out of a b.u.mp," New York Times, New York Times, April 19, 2006. April 19, 2006.

are to violate them: Drivers, it turns out, already tend to treat stop signs like "Slow" signs. A study by Michael DeCesare that looked at a sample of 2,390 vehicles at several intersections in the northeastern United States found that only 14 percent of the group came to a complete stop. Most drivers simply "paused," and those that did come to a complete stop often did so only because there were already other cars crossing through the intersection. Interestingly, no cars completely violated the stop signs, which implies that stop-sign visibility was not an issue. See "Behavior at Stop Sign Intersections: A Matter of Convenience and Threat of Danger," paper presented at the Annual Meeting of the Eastern Sociological Society, Boston, 1999.

to make up time: See, for example, Gerald L. Ullman, "Neighborhood Speed Control-U.S. Practices," ITE Compendium of Technical Papers ITE Compendium of Technical Papers (1996), pp. 11115, and Richard F. Beaubein, "Controlling Speeds on Residential Streets," (1996), pp. 11115, and Richard F. Beaubein, "Controlling Speeds on Residential Streets," ITE Journal, ITE Journal, April 1989, pp. 3739. April 1989, pp. 3739.

time to speed: Reid Ewing, "U.S. Experience with Traffic Calming," Inst.i.tute of Transportation Engineers Journal, Inst.i.tute of Transportation Engineers Journal, August 1997, p. 30. August 1997, p. 30.

to these trips: Crysttal Atkins and Michael Coleman, "Influence of Traffic Calming on Emergency Response Times," Inst.i.tute of Transportation Engineers Journal, Inst.i.tute of Transportation Engineers Journal, August 1997. August 1997.

"fatigue of getting upstairs": Charles d.i.c.kens, "Street Accidents," All the Year Round, All the Year Round, vol. 8 (1892; repr.), p. 499. vol. 8 (1892; repr.), p. 499.

often without supervision: For a good history of the woonerven, woonerven, see Michael Southworth and Eran Ben-Joseph, see Michael Southworth and Eran Ben-Joseph, Streets and the Shaping of Towns and Cities Streets and the Shaping of Towns and Cities (New York: McGraw-Hill, 1996). (New York: McGraw-Hill, 1996).

acting accordingly in the moment: Interestingly, this idea has had precedents here and there in the history of traffic engineering. In July 1927, the American magazine Nation's Traffic Nation's Traffic reported on a novel signal system at a four-way intersection that featured white lights instead of the traditional amber. When the lights in all four directions shone white, it signified that cars in all four directions could make left turns. Instead of mayhem during the evening rush hour, the writer reported, "We saw four streams of traffic making left turns at the same time...without the sc.r.a.ping of a fender." The local police chief made an interesting observation: "We have taught these people to sort of care for themselves." From Gordon Sessions, reported on a novel signal system at a four-way intersection that featured white lights instead of the traditional amber. When the lights in all four directions shone white, it signified that cars in all four directions could make left turns. Instead of mayhem during the evening rush hour, the writer reported, "We saw four streams of traffic making left turns at the same time...without the sc.r.a.ping of a fender." The local police chief made an interesting observation: "We have taught these people to sort of care for themselves." From Gordon Sessions, Traffic Devices: Historical Aspects Thereof Traffic Devices: Historical Aspects Thereof (Washington, Inst.i.tute of Traffic Engineers, 1971), p. 50. (Washington, Inst.i.tute of Traffic Engineers, 1971), p. 50.

the less we see: This is particularly true at roundabouts. An observational study in Finland found that drivers entering a roundabout were less likely to look to the right and more likely to violate the right-of-way of cyclists crossing to the right. See Heikki Summala and Mikko Rasanen, "Top-Down and Bottom-Up Processes in Driver Behavior at Roundabouts and Crossroads," Transportation Human Factors, Transportation Human Factors, vol. 2, no. 1 (2000), pp. 2937. vol. 2, no. 1 (2000), pp. 2937.

around 20 miles per hour: When I presented this theory to Daniel Lieberman, a professor of biological anthropology at Harvard University's Skeletal Biology Lab, he answered, via e-mail: "I would agree with you that natural selection would have to have permitted the skeleton to survive falls from running and other such natural events, but we were never designed to be hit by 1-ton cars going at 60 MPH (a lot of momentum). But is running the highest natural force a body experiences? Not sure. We also got hit on the head, attacked by saber-tooths, etc. But it is clearly the case that running is a common way to injure ourselves since we are naturally awkward unstable creatures more likely to fall than quadrupeds, and more likely to get injured by a fall (farther to go). So you might indeed be right."

running a red light: In 2000, for example, more than one thousand people were killed in crashes caused by someone running a red light, according to the Federal Highway Administration. Figure retrieved from http://safety.fhwa.dot.gov/intersections/comm_rlrfaq.htm.

people on foot: This raises the question of what happens at intersections without "Walk"/"Don't Walk" signals. Picture the mayhem as ill-behaved pedestrians cross w.i.l.l.y-nilly without being told when to do so. At the time of this writing, it was possible to see this in New York City (although plans were afoot to install pedestrian signals). Simply go to Park Avenue, anywhere from Forty-sixth Street to Fifty-sixth Street. There you will notice that not only are the traffic lights smaller but there are no pedestrian crossing signals (called "ped heads"). For unique structural reasons owing to a commuter train running underneath the street, traffic authorities for years were unable to install the necessary foundation for a standard signal. So are pedestrians. .h.i.t by cars more frequently at these corners? A five-year "crash map" put together by the city DOT showed that there were no more pedestrians struck in that section of Park Avenue than in the areas immediately to the north and south that had ped heads. This suggests that pedestrians on those blocks were forced to more actively a.s.sess the danger posed by cars. The crash map was put together by the New York City Department of Transportation's Pedestrian Projects office and was supplied to me by Michael King. To fully a.s.sess the actual risk faced by pedestrians at those sections of Park Avenue versus other areas, and the reasons why, a comprehensive study would have to be undertaken to determine pedestrian volumes and a.n.a.lyze the causative factors of the crashes. If more pedestrians are struck at those corners, the reason might also have to do with the below-standard traffic signals for vehicles. As Michael Primeggia, the deputy commissioner at the city's Department of Transportation, noted to me in a conversation, vehicle vehicle crashes are higher at those corners; particularly "right-angle collisions," which are often attributed to a car's failure to stop at a red. crashes are higher at those corners; particularly "right-angle collisions," which are often attributed to a car's failure to stop at a red.

their own green light: This is why engineers often install the "leading pedestrian interval," or LPI, which gives an "exclusive phase" of a few seconds or so to the walker, to give him a head start and allow him to a.s.sert his authority in the crosswalk. This, of course, slows vehicular traffic flow. The most radical example of a pedestrian-only phase is the so-called Barnes dance, named after New York City's longtime traffic commissioner, in which pedestrians are given the "Walk" signal in both directions and cars in all all directions must wait. The Barnes dance was not actually invented in New York City, as is often thought, but in Barnes's previous posting of Denver. After he unveiled an all-way pedestrian phase, a local scribe wrote, "Barnes has made the people so happy they're dancing in the streets" hence the Barnes dance. See Henry Barnes, directions must wait. The Barnes dance was not actually invented in New York City, as is often thought, but in Barnes's previous posting of Denver. After he unveiled an all-way pedestrian phase, a local scribe wrote, "Barnes has made the people so happy they're dancing in the streets" hence the Barnes dance. See Henry Barnes, The Man with Red and Green Eyes The Man with Red and Green Eyes (New York: Dutton, 1965), p. 116. (New York: Dutton, 1965), p. 116.

for the health of pedestrians: D. F. Preusser, W. A. Leaf, K. B. Debartla, and R. D. Blomberg, The Effects of Right-Turn-on-Red on Pedestrians and Bicycle Accidents, The Effects of Right-Turn-on-Red on Pedestrians and Bicycle Accidents, NHTSA-DOT/HS-806/182 (Dunlap and a.s.sociates, Darien, Conn.: October 1981). NHTSA-DOT/HS-806/182 (Dunlap and a.s.sociates, Darien, Conn.: October 1981).

law than while not: In a study that looked at a year's worth of pedestrian and bicycle fatalities (1997), drivers were found to be "at least partly culpable" in 71 percent of the cases. See Charles Komanoff, "Killed by Automobile: Death in the Streets in New York City, 19941997," March 1999. In 2004, nearly one-third of all pedestrians killed in New York City were killed in the crosswalk of an intersection. Of all the pedestrian fatalities, the majority (114, or 67.5 percent) were not attributed to any action by the pedestrian, while the categories that reasonably indicate pedestrian blame ("darting, running, or stumbling into road," "improper crossing of roadway or intersection," "failure to obey traffic control devices, traffic officers, traffic laws, etc.," and "walking, playing, working in roadway") total 48 of 169 fatalities, or roughly 28 percent. See Claire E. McKnight, Kyriacos Mouskos, Camille Kamga, et al., NYMTC Pedestrian Safety Study, NYMTC Pedestrian Safety Study, Inst.i.tute for Transportation Systems, City University of New York; prepared for the New York Metropolitan Transportation Council, February 27, 2007. Inst.i.tute for Transportation Systems, City University of New York; prepared for the New York Metropolitan Transportation Council, February 27, 2007.

must navigate several lanes: The undisputed king of marked crosswalk studies is Charles Zegeer, at the University of North Carolina. See Charles V. Zegeer, J. Stewart, and H. Huang, Safety Effects of Marked Versus Unmarked Crosswalks at Uncontrolled Locations: Executive Summary and Recommended Guidelines, 19962001 Safety Effects of Marked Versus Unmarked Crosswalks at Uncontrolled Locations: Executive Summary and Recommended Guidelines, 19962001 (Washington, D.C.: Federal Highway Administraion, March 2002); available at (Washington, D.C.: Federal Highway Administraion, March 2002); available at http://www.walkinginfo.org/pdf/r&d/crosswalk_021302.pdf make things safer: See David R. Ragland and Meghan Fehlig Mitman, "Driver/Pedestrian Understanding and Behavior at Marked and Unmarked Crosswalks," U.C. Berkeley Traffic Safety Center, Paper UCB-TSC-RR-2007-4, July 1, 2007; http://repositories.cdlib.org/its/tsc/UCB-TSC-RR-2007-4. See also Meghan Fehlig Mitman and David R. Ragland, "What They Don't Know Can Kill Them," U.C. Berkeley Traffic Safety Center, Paper UCB-TSC-TR-2007-2, April 1, 2007; http://repositories.cdlib.org/its/tsc/UCB-TSC-TR-2007-2.

a good thing for pedestrians: Conversely, knowing traffic laws such as right-of-way can be dangerous. A study in Finland that looked at collisions between cars and bicycles found that while only 11 percent of cars reported seeing the bicyclist before the crash, some 68 percent of cyclists reported seeing the car-and 92 percent of those who noticed the car a.s.sumed it would yield the right-of-way. See Summala and Rasanen, "Top-Down and Bottom-Up Processes," op. cit.

of their own safety: One reason for this is the "multiple-threat collision," in which one driver stops but a driver in the next lane does not, most likely because his view of that pedestrian is blocked. This was described to me in a conversation with Charlie Zegeer at the University of North Carolina, a traffic-safety researcher who has spent more time than anyone studying the problems of getting pedestrians across the road safely. See also Zegeer, Stewart, and Huang, Safety Effects, Safety Effects, op. cit. op. cit.

in the face of oncoming traffic: M. Winnet, S. Farmer, J. Anderson, and R. Lockwood, "An Evaluation of the Effect of Removing White Centre Lines," report prepared for the Wiltshire County Council by CEEMA Ltd. and TRL Limited.

to drive faster: This is an old saw in traffic engineering. In the 1922 book Good Roads, Good Roads, for example, author James McConaghie notes that "it has been found that by placing a series of lines on the pavement, dividing the s.p.a.ce up into its maximum number of traffic lanes, a greater speeding up of traffic has been the result." Quoted in Sessions, for example, author James McConaghie notes that "it has been found that by placing a series of lines on the pavement, dividing the s.p.a.ce up into its maximum number of traffic lanes, a greater speeding up of traffic has been the result." Quoted in Sessions, Traffic Devices, Traffic Devices, p. 104. p. 104.

insufficiently wide bike lanes: See D. L. Harkey and J. R. Stewart, "Evaluation of Shared-Use Facilities for Bicycles and Motor Vehicles," Transportation Research Record 1578, Transportation Research Board, Washington, D.C., 1997. For a less scientifically rigorous but no less interesting report, see Pete Ownes, "The Effect of Cycle Lanes on Cyclists' Road s.p.a.ce," Warrington Cycle Campaign, October 2005. Other studies have made the point that bicycle lanes reduce the amount of vehicle "displacement"-that is, how much they veer toward the center line or even into the other lane-and that bicycles themselves stay on a straighter path in the presence of lanes. See Bonnie J. Kroll and Melvin R. Ramey, "Effects of Bike Lanes on Driver and Bicyclist Behavior," Journal of Transportation Engineering, Journal of Transportation Engineering, vol. 103, no. 2 (MarchApril 1977), pp. 24356, and S. R. McHenry and M. J. Wallace, vol. 103, no. 2 (MarchApril 1977), pp. 24356, and S. R. McHenry and M. J. Wallace, Evaluation of Wide Curb Lanes as Shared Lane Bicycle Facilities, Evaluation of Wide Curb Lanes as Shared Lane Bicycle Facilities, Report FHWA/MD-85/06, Maryland Department of Transportation, Baltimore, August 1985. Report FHWA/MD-85/06, Maryland Department of Transportation, Baltimore, August 1985.

system was more dangerous!: The Laweiplein information comes from an unpublished study by Jeroen van Doome and Jelmer Herder of the Leeuwarden Technical College. The data is still preliminary and, as in all such studies, it can be difficult to immediately attribute reasons for increases or decreases in crashes. There may still be lingering "novelty effects" in the scheme, as well as a possibility of a "regression to the mean," whereby statistical ent.i.ties such as crash statistics possess a natural tendency to fluctuate. More time will be needed to fully a.s.sess the scheme. The reader might well wonder whether the safety and traffic improvements made in Drachten could have been achieved by simply converting the s.p.a.ce to a conventional roundabout. But the Leeuwarden report notes that the traffic improvements at Drachten outperform what would be expected using modeling for a "conventional roundabout." Hamilton-Baillie pointed out to me in an e-mail that the geometry of the scheme differs from that of a conventional roundabout: "By narrowing the entrances and exits-they are 6 meters wide-there's very little flaring. It doesn't seem to be a problem for traffic to just allow pedestrians and bicycles to just filter through." The Laweiplein design, he maintains, avoids some of the problems of how to accommodate pedestrians and bicycles, a common criticism of roundabout schemes. On the idea that users thought the system was more dangerous, when it was statistically not, there is evidence that this kind of distortion is not uncommon. In a study conducted on the University of North Carolina at Chapel Hill campus, a group of students were surveyed as to what they thought the most dangerous areas on campus were for pedestrians. Some locations that people thought were "safe" had actually had a number of crashes, even more so than areas they labeled "dangerous." See R. J. Schneider, R. M. Ryznar, and A. J. Khattak, "An Accident Waiting to Happen: A Spatial Approach to Proactive Pedestrian Planning," Accident a.n.a.lysis & Prevention, Accident a.n.a.lysis & Prevention, vol. 36, no. 2 (March 2004), pp. 193211. vol. 36, no. 2 (March 2004), pp. 193211.

made on bicycles: From "Cycling for Everyone: The Key to Political and Public Support," by John Pucher, Rutgers University. Doc.u.ment retrieved from www.policy.rutgers.edu/faculty/pucher/BikeSummit2007COMP_Mar25.pdf on April 8, 2007. on April 8, 2007.

for minor injuries: The Kensington High Street statistics are found in Graeme Swinburne, "Report on Road Safety in Kensington High Street," Royal Borough of Kensington and Chelsea, London.

"for no inconsiderable time": Charles d.i.c.kens, Sketches by Boz Sketches by Boz (1835; repr. London: Penguin Cla.s.sics, 1996), p. 92. (1835; repr. London: Penguin Cla.s.sics, 1996), p. 92.

"you need freeways": Walter Kulash, of Glatting Jackson, described to me a similar tension in terms of traffic flow. "One thing we have learned," he said, "is that streets are always a bundle of competing interests. There is always going to be less of one thing if there is more of another thing. If there is more seclusion and streets are by their very layout incapable of carrying any through traffic...then a negative is going to pop up somewhere else. And that negative is unbearable arterial streets."

twelfth-deadliest road in America: Scott Powers, "Colonial One of Nation's Most Dangerous Roads," Orlando Sentinel, Orlando Sentinel, November 21, 2004. The U.S. 19 information is taken from a survey conducted by NBC's November 21, 2004. The U.S. 19 information is taken from a survey conducted by NBC's Dateline; Dateline; see Josh Mankiewicz, "Dangerous Roads," see Josh Mankiewicz, "Dangerous Roads," Dateline, Dateline, June 7, 2005. June 7, 2005.

would have deemed safer: For the details of Eric Dumbaugh's studies I have drawn on several sources. The first is his unpublished Ph.D. dissertation: "Safe Streets, Livable Streets: A Positive Approach to Urban Roadside Design" (Georgia Inst.i.tute of Technology, August 2005). I also used a related article: Eric Dumbaugh, "Safe Streets, Livable Streets," Journal of the American Planning a.s.sociation, Journal of the American Planning a.s.sociation, vol. 71, no. 3 (Summer 2005), pp. 283300. vol. 71, no. 3 (Summer 2005), pp. 283300.

26 to 30 miles per hour: National Highway Traffic Safety Administration, "Literature Review on Vehicle Travel Speeds and Pedestrian Injuries," DOT HS 809 021, October 1999.

by some 10 percent: See, for example, M. Martens, S. Comte, and N. Kaptein, "The Effects of Road Design on Speed Behavior: A Literature Review," Technical Research Centre of Finland VTT, Espoo, 1997. Moreover, a survey of street segments in Connecticut, Ma.s.sachusetts, and Vermont revealed that on-street parking itself seems to have a safety benefit. The researchers write: "Our results suggest that on-street parking can also help to create a safer environment. While this statement seems to contradict most of the existing research, the reality is that lower speed roads (less than 35 mph) with on-street parking have far less severe and fatal crashes. In fact, lower speed streets without parking had a severe and fatal crash rate more than two times higher than the streets with parking. We also showed conclusively that drivers tended to travel slower in the presence of features such as on-street parking and small building setbacks. Slower vehicle speeds provide pedestrians, cyclists, and drivers more time to react, and when a crash does occur, the chance of it being life-threatening is greatly reduced." See Wesley Marshall, Norman Garrick, and Gilbert Hansen, "Rea.s.sessing On-Street Parking," paper presented at the Transportation Research Board meeting, January 2008, Washington, D.C.

"roadside conditions": Richard F. Weingroff, "President Dwight D. Eisenhower and the Federal Role in Highway Safety" (Washington, D. C.: Federal Highway Administration, 2003), retrieved at http://www.fhwa.dot.gov/infrastructure/safety.htm.

they felt it was safer: N. J. Ward and G. J. S. Wilde, "Driver Approach Behaviour at an Unprotected Railway Crossing Before and After Enhancement of Lateral Sight Distances: An Experimental Investigation of a Risk Perception and Behavioural Compensation Hypothesis," Safety Science, Safety Science, vol. 22 (1996), pp. 6375. vol. 22 (1996), pp. 6375.

raise property values: See, for example, S. E. Maco and E. G. McPherson, "A Practical Approach to a.s.sessing Structure, Function, and Value of Street Tree Populations in Small Communities," Journal of Arboriculture, Journal of Arboriculture, vol. 29, no. 2 (March 2003). vol. 29, no. 2 (March 2003).

from roadsides for decades: In a 1941 Chicago planning study t.i.tled Subdivision Regulation, Subdivision Regulation, for example, the author, Harold Lautner, wrote: "While it has been customary in the past to plant street trees between the street curb and the pedestrian walk, an alternate procedure is now recommended as preferable in some cases. Trees planted along the street curb increase the severity of motor accidents and in turn are easily subjected to traffic injury...and except on very wide streets, curb planted trees crowd in upon the traveled way. To plant street trees on the property side of pedestrian walks, away from the pavement and traffic, seems more desirable, for example, the author, Harold Lautner, wrote: "While it has been customary in the past to plant street trees between the street curb and the pedestrian walk, an alternate procedure is now recommended as preferable in some cases. Trees planted along the street curb increase the severity of motor accidents and in turn are easily subjected to traffic injury...and except on very wide streets, curb planted trees crowd in upon the traveled way. To plant street trees on the property side of pedestrian walks, away from the pavement and traffic, seems more desirable, particularly on residential streets particularly on residential streets" (emphasis in original). This would, of course, not only increase the speed of pa.s.sing traffic, posing more of a risk to pedestrians, but would also remove a potential barrier to a car striking a pedestrian. From Southworth and Ben-Joseph, Streets and the Shaping of Towns and Cities, Streets and the Shaping of Towns and Cities, op. cit., p. 88. op. cit., p. 88.

Chapter Eight: How Traffic Explains the World.

same s.p.a.ce as New York City: This figure is taken from Richard L. Forstall, Richard P. Green, and James B. Pick, "Which Are the Largest: Why Published Populations for Major Urban Areas Vary So Greatly." Accessed from the University of IllinoisChicago "City Futures" conference Web site, http://www.uic.edu/cuppa/cityfutures/.

same lane as the cyclists: Dinesh Mohan, The Road Ahead: Traffic Injuries and Fatalities in India The Road Ahead: Traffic Injuries and Fatalities in India (New Delhi: Transportation Research and Injury Prevention Programme, Indian Inst.i.tute of Technology; 2004), pp. 130. (New Delhi: Transportation Research and Injury Prevention Programme, Indian Inst.i.tute of Technology; 2004), pp. 130.

but before: before: Lu Huapu, Shi Qixin, and Masato Iwasaki, "A Study on Traffic Characteristics at Signalized Intersections in Beijing and Tokyo," Tsinghua University, Lu Huapu, Shi Qixin, and Masato Iwasaki, "A Study on Traffic Characteristics at Signalized Intersections in Beijing and Tokyo," Tsinghua University, Proceedings of EASTS (The 2nd Conference of the Eastern Asia Society for Transportation Studies). Proceedings of EASTS (The 2nd Conference of the Eastern Asia Society for Transportation Studies).

would mean "stop": This story is discussed in Keesing's Research Report, The Cultural Revolution in China The Cultural Revolution in China (New York: Scribner, 1967), p. 18. (New York: Scribner, 1967), p. 18.

"can he actually overtake overtake": Kenneth Tynan, The Diaries of Kenneth Tynan The Diaries of Kenneth Tynan (New York: Bloomsbury, 2002), p. 101. (New York: Bloomsbury, 2002), p. 101.

the entire street: The journalist Jan Wong, writing about Beijing in the 1980s, reported that "even state-owned cars were so rare that most Beijing intersections lacked traffic lights. Stop signs were non-existent. At night, cars were required required to douse headlights to avoid blinding cyclists. With only a handful of vehicles on the road, no one worried about one car smashing into another in the dark." See to douse headlights to avoid blinding cyclists. With only a handful of vehicles on the road, no one worried about one car smashing into another in the dark." See Jan Wong's China Jan Wong's China (Toronto: Doubleday Canada, 1999), p. 212. (Toronto: Doubleday Canada, 1999), p. 212.

as a social good?: For a good discussion of Mao's "lawlessness" concept, see Chapter 10 of Zhengyuan Fu, Autocratic Tradition and Chinese Politics Autocratic Tradition and Chinese Politics (Cambridge: Cambridge University Press, 1993). (Cambridge: Cambridge University Press, 1993).

public morality and civic culture: See, for example, Wen-shun Chi, Ideological Conflicts in Modern China: Democracy and Authoritarianism Ideological Conflicts in Modern China: Democracy and Authoritarianism (New York: Transaction Publishers, 1986), p. 56. (New York: Transaction Publishers, 1986), p. 56.

"superior to them": This quote comes from "Moral Embarra.s.sment," Shanghai Star, Shanghai Star, August 11, 2001. August 11, 2001.

"rights by litigation": Albert H. Y. Chen, "Toward a Legal Enlightenment: Discussions in Contemporary China on the Rule of Law," UCLA Pacific Basin Law Journal, UCLA Pacific Basin Law Journal, vol. 17 (2000). vol. 17 (2000).

drive on the right: The information about which side of the road different countries drive on was obtained from Peter Kincaid's exhaustive treatise The Rule of the Road: An International Guide to History and Practice The Rule of the Road: An International Guide to History and Practice (New York: Greenwood Press, 1986). (New York: Greenwood Press, 1986).

violation of the standard: The flashing of headlights in Europe also seems to be bluntly effective at getting people to move over. As a study of Austrian highway behavior showed, while demographic factors explained which drivers tended to drive faster and tailgate more aggressively (men driving expensive cars, as you might expect), there was also what the author called an "instrumental function"-the urge to "dominate" other drivers seemed to be the most effective way to encourage them to move over. "It was found that drivers who approach to under ten meters behind the camera car were more likely to displace the driver ahead," the authors wrote. "Furthermore, drivers who approached faster displaced others more effectively." Klaus Atzw.a.n.ger and B. Ruso, in Vision in Vehicles VI Vision in Vehicles VI (Amsterdam: Elsevier Science B.V., 1999), p. 197. (Amsterdam: Elsevier Science B.V., 1999), p. 197.

confusing array of laws: See, for example, the Web site maintained by John Carr, http://www.mit.edu/~jfc/right.htm.

rights have been violated: George McDowell, an economist at Virginia Tech, has offered the fascinating theory that a country's traffic behavior is reflected in its economic system. In the United States, the supposed "free market" is, he argues, instead an "open market," in which "rules, both formal and informal, govern behavior. Opportunistic behavior is expected and even encouraged but within a strict set of parameters." In China, however, he argues, the system is better described as a "free market," where "the only rule is caveat emptor." The Chinese system of what he calls "advantage" means that horns are used less as a means to signal "road rage" but more to "notify other vehicles that you are there and will not give way." Advantage "is gained," he writes, "exploited by the person who gained it, and accepted by the person bested." In the United States this acceptance is less likely to occur. See George R. McDowell, "The Market as Traffic: An Economic Metaphor," Journal of Economic Issues, Journal of Economic Issues, vol. 38 (2004), pp. 27074. vol. 38 (2004), pp. 27074.

acts more personally: American roads are also more crowded than the expensive Italian autostrada. autostrada. This brings up the issue that it may be more difficult for drivers to "get over" and meet the demands of the driver to the rear; there is also the larger issue that giving up an entire lane to a few people wishing to go fast, with all the lane changing that entails, can be poor use of the traffic network. This brings up the issue that it may be more difficult for drivers to "get over" and meet the demands of the driver to the rear; there is also the larger issue that giving up an entire lane to a few people wishing to go fast, with all the lane changing that entails, can be poor use of the traffic network.

fairness and equality: According to the political scientist Robert Putnam, this dynamic is more prevalent in the southern regions of Italy. These, he argued, have historically lacked a strong civic culture, being dominated instead by feudalistic patronage relationships and an "amoral familism"-worry about yourself and trust that everyone will look after themselves. Instead of "horizontal" networks of reciprocal relations and trust among the community, Putnam argues, the south has been dominated by more vertical, patron-client-style relationships. From Robert Putnam, Making Democracy Work: Civic Traditions in Modern Italy Making Democracy Work: Civic Traditions in Modern Italy (Princeton: Princeton University Press, 1993). (Princeton: Princeton University Press, 1993).

jaywalking: The historian Peter Norton, in an exemplary article, traces the etymology of the word to at least 1909, well before the 1917 Boston usage registered by the second edition of the The historian Peter Norton, in an exemplary article, traces the etymology of the word to at least 1909, well before the 1917 Boston usage registered by the second edition of the Oxford English Dictionary Oxford English Dictionary in 1989. Norton traces the rise of the word in the popular imagination as pedestrians saw gradually eroded their longstanding right to a shared use of city streets, in favor of a historically unprecedented edict, as described by one writer, upon the arrival of the automobile: "The streets are for vehicle traffic, the sidewalks for pedestrians." Jaywalking, in essence, marginalized and even criminalized what had been standard urban behavior. This was done ostensibly in the name of safety, but as Norton notes, its real aim was to clear urban streets for the increased circulation of vehicular traffic (other, potentially more effective, safety measures like speed "governors" for cars were overridden by motoring interests). Peter D. Norton, "Street Rivals: Jaywalking and the Invention of the Motor Age Street," in 1989. Norton traces the rise of the word in the popular imagination as pedestrians saw gradually eroded their longstanding right to a shared use of city streets, in favor of a historically unprecedented edict, as described by one writer, upon the arrival of the automobile: "The streets are for vehicle traffic, the sidewalks for pedestrians." Jaywalking, in essence, marginalized and even criminalized what had been standard urban behavior. This was done ostensibly in the name of safety, but as Norton notes, its real aim was to clear urban streets for the increased circulation of vehicular traffic (other, potentially more effective, safety measures like speed "governors" for cars were overridden by motoring interests). Peter D. Norton, "Street Rivals: Jaywalking and the Invention of the Motor Age Street," Technology and Culture, Technology and Culture, vol. 48 (April 2007), pp. 33159. vol. 48 (April 2007), pp. 33159.

in which he was raised: Aksel Sandemose, A Fugitive Crosses His Tracks A Fugitive Crosses His Tracks (New York: Alfred A. Knopf, 1936). (New York: Alfred A. Knopf, 1936).

rules of grammar: Sanford W. Gregory Jr. compared traffic behavior in Egypt to a "verdant grammar," one not "yet ripened by centuries of social-interactive maturation." The arrival of ma.s.s driving in Egypt, he suggests, happened too quickly for Western traffic patterns to be inst.i.tutionalized, so instead a kind of pidgin or creole language was formed, with distinct rules, as is often the case "when mature speakers of diverse dominant language groups meet." Without time to create a formal order of its own, Egypt's drivers invented a brutally effective slang of sorts. Gregory commented that this seemed based more on eye contact and informal signals than in the West. See Gregory, "Auto Traffic in Egypt as a Verdant Grammar," Social Psychology Quarterly, Social Psychology Quarterly, vol. 48, No. 4 (December 1985), pp. 33748. vol. 48, No. 4 (December 1985), pp. 33748.

each side of the street: This story is mentioned in William Muray, City of the Soul: A Walk in Rome City of the Soul: A Walk in Rome (New York: Crown, 2003), p. 26. (New York: Crown, 2003), p. 26.

Mythological status: H. V. Morton, in his 1957 travelogue A Traveler in Rome, A Traveler in Rome, observed, while riding in a taxi: "The cars around us, which were traveling just as fast as we were, swerved aside by one of those instinctive Italian motoring movements not unlike birds in formation who part and form again" (1957; repr., New York: Da Capo, 2002), p. 135. observed, while riding in a taxi: "The cars around us, which were traveling just as fast as we were, swerved aside by one of those instinctive Italian motoring movements not unlike birds in formation who part and form again" (1957; repr., New York: Da Capo, 2002), p. 135.

one-fifth of the traffic: Michele Faberi, Marco Martuzzi, and Franco Pirrami, a.s.sessing the Health Impact and Social Costs of Mopeds: Feasibility Study in Rome a.s.sessing the Health Impact and Social Costs of Mopeds: Feasibility Study in Rome (Rome: World Health Organization, 2004), p. xvii. (Rome: World Health Organization, 2004), p. xvii.

fewer riders wear helmets: The helmet-use rates come from F. Servadei, C. Begliomini, E. Gardini, M. Giustini, F. Taggi, and J. Kraus, "Effect of Italy's Motorcycle Helmet Law on Traumatic Brain Injuries," Injury Prevention, Injury Prevention, vol. 9, no. 3 (2003), pp. 25760. vol. 9, no. 3 (2003), pp. 25760.

collisions with cars: Giuseppe Latorre, Giuliano Bertazzoni, Donato Zotta, Edward Van Beeck, and Gualtiero Ricciardi, "Epidemiology of Accidents Among Users of Two-Wheeled Motor Vehicles: A Surveillance Study in Two Italian Cities," European Journal of Public Health, European Journal of Public Health, vol. 12, no. 2 (2002), pp. 99103. vol. 12, no. 2 (2002), pp. 99103.

(and getting away with it): R. B. Cialdini, L. J. Demaine, B. J. Sagarin, D. W. Barrett, K. Rhoads, and P. L. Winter, "Managing Social Norms for Persuasive Impact," Social Influence, Social Influence, vol. 1 (2006), pp. 315. vol. 1 (2006), pp. 315.

behavior either way: There have been several studies of jaywalking and model behavior. See, for instance, Monroe Lefkowitz, Robert R. Blake, and Jane Srygley Mouton, "Status Factors in Pedestrian Violation of Traffic Signals," Journal of Abnormal and Social Psychology, Journal of Abnormal and Social Psychology, vol. 51 (1955), pp. 70406, and Brian Mullen, Carolyn Copper, and James E. Driskell, "Jaywalking as a Function of Model Behavior," vol. 51 (1955), pp. 70406, and Brian Mullen, Carolyn Copper, and James E. Driskell, "Jaywalking as a Function of Model Behavior," Personality and Social Psychology Bulletin, Personality and Social Psychology Bulletin, vol. 16, no. 2 (1990), pp. 32030. vol. 16, no. 2 (1990), pp. 32030.

are famously orderly: Joe Moran makes the point that people in England have been "complaining about the disintegration of queue discipline for almost as long as they have been lauding the queue as the essence of British decency-perhaps because this myth carries such symbolic weight that it cannot be sustained by the necessarily messier reality." From Joe Moran, Queuing for Beginners Queuing for Beginners (London: Profile Books, 2007), p. 92. (London: Profile Books, 2007), p. 92.

more in theory than reality: Liu Shinan argues that Chinese do queue up when queuing itself is the norm: "We queue where we are accustomed to queue, for example, at a cinema booking office or at the cashier's counter in a supermarket. In many places where we are not accustomed to queue, however, we do not queue-for example, in front of an elevator or subway door." Liu Shinan, "Behavior of Tourists Has No Quick Fix," China Daily, China Daily, November 10, 2006. November 10, 2006.

to be slight: One study found the correlation between "service quality" and tipping to be just 0.07 percent. See Michael Conlin, Ted O'Donohue, and Michael Lynn, "The Norm of Restaurant Tipping," Journal of Economic Behavior and Organization, Journal of Economic Behavior and Organization, vol. 52 (2003), pp. 297321. For an excellent overview of the quite extensive academic literature on tipping, I recommend the work of Ofer Azar, an economist at Ben-Gurion University of the Negev in Israel, particularly "The Social Norm of Tipping: A Review," vol. 52 (2003), pp. 297321. For an excellent overview of the quite extensive academic literature on tipping, I recommend the work of Ofer Azar, an economist at Ben-Gurion University of the Negev in Israel, particularly "The Social Norm of Tipping: A Review," Journal of Applied Social Psychology, Journal of Applied Social Psychology, vol. 37, no. 2 (2007), pp. 380402. vol. 37, no. 2 (2007), pp. 380402.

"obeying the law": See Amir Licht, "Social Norms and the Law: Why People Obey the Law," a working paper available at http://www.faculty.idc.ac.il/licht/papers.htm.

to nearly 84,000: Sheng-Yong w.a.n.g, Gui-Bo Chi, Chun-Xia Jing, Xiao-Mei Dong, Chi-Peng Wu, and Li-Ping Li, "Trends in Road Traffic Crashes and a.s.sociated Injury and Fatality in the People's Republic of China, 19511999," Injury Control and Safety Promotion, Injury Control and Safety Promotion, vol. 10, nos. 12 (2003), pp. 8387. vol. 10, nos. 12 (2003), pp. 8387.

roughly 49 million: New York Times, New York Times, July 22, 1951. July 22, 1951.

Smeed's law: R. J. Smeed, "Some Statistical Aspects of Road Safety Research," Journal of the Royal Statistical Society, Series A (General), Journal of the Royal Statistical Society, Series A (General), vol. 112, no. 1 (1949), pp. 134. vol. 112, no. 1 (1949), pp. 134.

as low as 10 percent: Vinand M. Nantulya and Michael R. Reich, "The Neglected Epidemic: Road Traffic Injuries in Developing Countries," British Medical Journal, British Medical Journal, May 2002, pp. 113941. May 2002, pp. 113941.

a staggering 80 percent: Mohan, The Road Ahead, The Road Ahead, op. cit. pp. 130. op. cit. pp. 130.

onto the same thoroughfare: In a discussion paper for the World Bank, Christopher Willoughby notes that "the current problems of motorization seem not generally to result from its occurring at lower per capita income levels, or more rapidly, than in the countries which coped with it reasonably satisfactorily in earlier years; it also grew very fast there for prolonged periods, especially in France (and Germany). The problems tend to be connected rather with the higher concentration of national population, economic activity and motorization itself in one or a very few major cities, at times when those cities are also increasing in size and population much more rapidly than was the case in Europe or j.a.pan." From Christopher Willoughby, "Managing Motorization," Discussion Paper TWU-42, World Bank; available at: http://www.world-bank.org/transport/publicat/twu_42.pdf.

nearly 100 percent: For a fascinating discussion of history of automobile insurance in China and recent reforms, see J. Tim Query and Daqing Huang, "Designing a New Automobile Insurance Pricing System in China: Actuarial and Social Considerations," Casualty Actuarial Society Forum, Casualty Actuarial Society Forum, Winter 2007. Winter 2007.

to West Germany's 130: Flaura K. Winston, Craig Rineer, Rajiv Menon, and Susan P. Baker, "The Carnage Wrought by Major Economic Change: Ecological Study of Traffic Related Mortality and the Reunification of Germany," British Medical Journal, British Medical Journal, vol. 318 (June 19, 1999), pp. 164750. vol. 318 (June 19, 1999), pp. 164750.

begin to accelerate: See Richard Dahl, "Heavy Traffic Ahead: Car Culture Accelerates," Environmental Health Perspectives, Environmental Health Perspectives, April 2005. April 2005.

Maureen Cropper shows: Elizabeth Kopits and Maureen Cropper, "Traffic Fatalities and Economic Growth," Accident a.n.a.lysis & Prevention, Accident a.n.a.lysis & Prevention, vol. 37 (2005), pp. 16978. vol. 37 (2005), pp. 16978.