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Location: essex ma
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i bike alot in a city and cannot count the number of times that i have had had at the least hair-raising encounters and at worst had my life put in jeopardy because some fucktard in a car was talking on their cell while driving. but then, i only really notice the people on cells who apparently do not do well with that particular multitasking thing: blowing red lights, turning irrationally, failing to use directionals so that cyclists can know that a change in relation to a large speeding metal thing near them is about to happen, speeding up or slowing down irrationally...it's great....
to the question at hand, a couple articles about stats.
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Finally, empirical proof you can blame chatty 20-somethings for stop-and-go traffic on the way to work.
A new study confirms that the reaction time of cell phone users slows dramatically, increasing the risk of accidents and tying up traffic in general, and when young adults use cell phones while driving, they're as bad as sleepy septuagenarians.
"If you put a 20-year-old driver behind the wheel with a cell phone, their reaction times are the same as a 70-year-old driver who is not using a cell phone," said University of Utah psychology professor David Strayer. "It's like instantly aging a large number of drivers."
The study was announced today and is detailed in winter issue of the quarterly journal Human Factors.
Traffic jams and death
Cell phone distraction causes 2,600 deaths and 330,000 injuries in the United States every year, according to the journal's publisher, the Human Factors and Ergonomics Society.
Are Cell Phones Really So Dangerous?
Drivers talking on cell phones were 18 percent slower to react to brake lights, the new study found. In a minor bright note, they also kept a 12 percent greater following distance. But they also took 17 percent longer to regain the speed they lost when they braked. That frustrates everyone.
"Once drivers on cell phones hit the brakes, it takes them longer to get back into the normal flow of traffic," Strayer said. "The net result is they are impeding the overall flow of traffic."
Strayer and his colleagues have been down this road before. In 2001, they found that even hands-free cell phone use distracted drivers. In 2003 they revealed a reason: Drivers look but don't see, because they're distracted by the conversation. The scientists also found previously that chatty motorists are less adept than drunken drivers with blood alcohol levels exceeding 0.08.
Separate research last year at University of Illinois at Urbana-Champaign supported the conclusion that hands-free cell phone use causes driver distraction.
"With younger adults, everything got worse," said Arthur Kramer, who led the Illinois study. "Both young adults and older adults tended to show deficits in performance. They made more errors in detecting important changes and they took longer to react to the changes."
The impaired reactions involved seconds, not just fractions of a second, so stopping distances increased by car-lengths.
Older drivers more cautious
The latest study used high-tech simulators. It included people aged 18 to 25 and another group aged 65 to 74. Elderly drivers were slower to react when talking on the phone, too.
The simulations uncovered a twofold increase in the number of rear-end collisions by drivers using cell phones.
Older drivers seem to be more cautious overall, however.
"Older drivers were slightly less likely to get into accidents than younger drivers," Strayer said. "They tend to have a greater following distance. Their reactions are impaired, but they are driving so cautiously they were less likely to smash into somebody." But in real life, he added, older drivers are significantly more likely to be rear-ended because of their slow speed.
Other studies in the journal found:
Telephone numbers presented by automated voice systems compete for drivers' attention to a far greater extent than when the driver sees the same information presented on a display.
Interruptions to driving, such as answering a call, are likely to be more dangerous if they occur during maneuvers like merging to exit a freeway.
Things could get worse. Wireless Internet, speech recognition systems and e-mail could all be even more distracting.
Are Cell Phones Really So Dangerous?
Posted Feb. 2, 2005 at 10:15 a.m. ET
Several readers wrote to LiveScience questioning whether cell phones were really so bad for drivers. Here is some additional information that helps illuminate the death statistic.
The estimates of annual deaths reported in this week's article (2,600) may well be low. The number, for U.S. deaths related to drivers using cell phones, comes from a 2002 study by the Harvard Center for Risk Analysis (HCRA). Researchers then estimated that the use of cell phones by drivers caused approximately 2,600 deaths.
Because data on cell phone use by motorists are limited, the range of uncertainty is wide, those researchers said. The estimate of fatalities in that HCRA report ranged between 800 and 8,000.
Importantly, the researchers noted (in 2002) that increasing cell phone use could be expected to cause the annual death estimate to rise. The 2002 estimate, for example, was up from an estimate of 1,000 deaths in the year 2000. Logic suggests the number -- though just an estimate -- could be much higher in 2005.
The estimates are based largely on mathematical models, but they are not without basis. In 2001 in California, for example, "at least 4,699 reported accidents were blamed on drivers using cell phones, and those crashes killed 31 people and injured 2,786," according to an analysis by The Los Angeles Times. That number can expected to be low, because of the lack of formal procedures for noting cell phone use as a cause of a traffic accident.
The Times also noted a 1997 study of Canadian drivers "who agreed to have their cell phone records scrutinized found that the risk of an accident was four times greater while a driver was using the phone."
Each year, about 42,000 people die in U.S. auto accidents.
Here is how the new University of Utah simulations were conducted:
Participants in the simulator used dashboard instruments, steering wheel and brake and gas pedals from a Ford Crown Victoria sedan, surrounded by three screens showing freeway scenes and traffic, including a "pace car" that intermittently hit its brakes 32 times as it appeared to drive in front of study participants.
If a participant failed to hit their own brakes, they eventually would rear-end the pace car. Each participant drove four simulated 10-mile freeway trips lasting about 10 minutes each, talking on a cell phone with a research assistant during half the trips and driving without talking the other half. Only hands-free phones were used to eliminate any possible distraction from manipulating a hand-held cell phone.
Thirty times each second, the simulator measured the participants' driving speed, following distance and - if applicable - how long it took them to hit the brakes and how long it took them to regain speed.
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source: http://www.livescience.com/technolog...ll_danger.html
but....
Quote:
Cell Phone Use and Traffic Accidents, Revisited
by Fred Hooven, M.S., and Sandra Sulsky, Ph.D., Applied Epidemiology, Inc.
Figure 1: How use of a cell phone immediately after an accident could end up being recorded by researchers as occurring before the accident
A recent study on cell phone use and driving behaviors (Does Cell Phone Conversation Impair Driving Performance?) found that having a cell phone conversation during a driving simulation impaired driving performance. Laboratory studies such as this have the advantage of being able to carefully control the administration of a hypothesized risk factor - exposure - such as a cell phone conversation. But laboratory studies are limited in their ability to assess the effect of cell phone use on the actual outcomes of greatest concern - traffic accidents and resulting injuries or fatalities. For such real-life conditions, epidemiology may provide a better picture of reality than can be achieved in the lab.
Most of the epidemiological studies to date have found indications of a link between cell phone use and auto accidents, but a causal connection has been extremely difficult to establish. This is in part due to two separate but related methodological issues: exposure assessment and confounding.
Exposure Assessment is often challenging in epidemiological research. First, the exposure must be defined in a measurable way. Is the presence of a cell phone in a car of interest? Ownership of a cell phone? Hours of phone use per month? The action of dialing a phone while driving? Being engaged in a potentially attention-diverting conversation? Each of these definitions of exposure carries with it certain assumptions, and accompanying threats to the validity of the study.
For instance, ownership of a cell phone may be easy to ascertain, but this broad definition of exposure leaves the analysis vulnerable to confounding. Confounding occurs when a third factor is associated with both the exposure and the outcome. If people who own cell phones have more car accidents than those who do not, how do we know if the higher accident rate is due to cell phone use while driving, as opposed to characteristics associated with cell phone ownership? These might include impatience, fast driving, or a tendency to engage in multitasking.
Defining the exposure more narrowly could help to reduce confounding. In this case, one could narrow the exposure definition to "phone use just prior to an accident." The problem then becomes one of measurement. If we fail to correctly classify those who were on the phone at the time of an accident versus those who were not, we may lose the ability to detect an effect, or an effect might be exaggerated. This issue of misclassification of exposure was highlighted by Tom and Ray Magliozzi - "Click and Clack" - of National Public Radio's "Car Talk." They criticized a widely publicized study sponsored by the AAA's Foundation for Traffic Safety that found cell phone use did not increase the risk of accidents as much as other driver-distractions. The radio hosts argued that the study's use of self-reports by drivers - made to police at the accident scene - was likely to result in substantial misclassification of exposure.
In contrast, Redelmeier and Tibshirani (New England Journal of Medicine, Feb. 13, 1997) matched the times of cell phone use recorded on phone bills with the times of accidents given in police reports. This approach offers a good example of an attempt to reduce exposure misclassification. By completely separating the ascertainment of the exposure (the phone call) from the report of the event (the accident), it was less likely that the outcome could influence the reported phone use. But, there is still a risk of exposure misclassification. These researchers assumed precise recording of both the time of the accident and the time of the call. Misclassification could result if there were only a few minutes difference in the time standards used by the phone company and by the person reporting the accident. The figure depicts how the use of a cell phone immediately after an accident could end up being recorded by researchers as occurring before the accident.
Research into the association between traffic accidents and use of cell phones highlights both some strengths (a closer relation to real-life than can be achieved in the lab) and some weaknesses (difficulty in defining, measuring, and classifying exposure) of field research. Such methodological difficulties do not mean, however, that policy makers should dismiss the findings of epidemiological studies. The four-fold increase in risk found in the study by Redelmeier and Tibshirani is unlikely to be due to confounding and measurement error alone. But no single approach can determine the degree to which using a cell phone while driving poses a safety hazard. A clearer picture will result by examining studies using a range of approaches - epidemiological, on-road observation, and off-road simulation.
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source: http://www.nsc.org/issues/idrive/cellfone.htm
so my position is based on anecdotal evidence, above.
and there are problems with the way studies as to broader patterns measure the relation of cell usage to accidents.
i dislike cars and would prefer to see them effectively banned from most cities. redesign the public transit systems so that cars remain on the periphery--it would improve the quality of life, reducing congestion, pollution--it would in general make cities safer places to be for everyone (dont believe me? try cycling on a friday afternoon in anything like a congested area)
and would be a step toward reducing petrochemical consumption. i would support local laws, generated by cities, that would put this into effect.
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a gramophone its corrugated trumpet silver handle
spinning dog. such faithfulness it hear
it make you sick.
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