Cell Phones Increase Traffic, Pedestrian Fatalities
Cell phones are a danger on the road in more ways than one. Two new studies show that talking on the phone while traveling, whether you're driving or on foot, is increasing both pedestrian deaths and those of drivers and passengers, and recommend crackdowns on cell1 use by both pedestrians and drivers.
The new studies, lead-authored by Rutgers University, Newark, Economics Professor Peter D. Loeb2, relate the impact of cell phones on accident fatalities to the number of cell phones in use, showing that the current increase in deaths resulting from cell phone use follows a period when cell phones actually helped to reduce pedestrian and traffic fatalities. However, this reduction in fatalities disappeared once the numbers of phones in use reached a "critical mass" 3 of 100 million, the study found.These studies looked at cell phone use and motor vehicle accidents from 1975 through 2002, and factored in4 a number of variables, including vehicle speed, alcohol consumption, seat belt use, and miles driven. The studies found the cell phone-fatality correlation to be true even when including factors such as speed, alcohol consumption, and seat belt use.
Loeb and his co-author determined that, at the current time, cell phone use has a "significant adverse effect on pedestrian safety" and that “cell phones and their usage above a critical thresholds adds to motor vehicle fatalities." In the late 1980s and part of the 1990s, before the numbers of phones exploded, cell phone use actually had a "life-saving effect" in pedestrian and traffic accidents, Loeb notes. "Cell-phone users' were able to quickly call for medical assistance when involved in an accident. This quick medical response actually reduced the number of traffic deaths for a time," Loeb hypothesizes.
However, this was not the case when cells were first used in the mid-1980s, when they caused a "life-taking effect" among pedestrians, drivers and passengers in vehicles. In those early days, when there were fewer than a million phones, fatalities increased, says Loeb, because drivers and pedestrians probably were still adjusting to the novelty of using them, and there weren't enough cell phones in use to make a difference in summoning help following an accident, he explains.
The "life-saving effect" occurred as the volume of phones grew into the early 1990s, and increasing numbers of cells were used to call 911 following accidents, leading to a drop in fatalities, explains Loeb. But this life-saving effect was canceled out6 once the numbers of phones reached a "critical mass" of about 100 million and the "life-taking effect" - increased accidents and fatalities outweighed the benefits of quick access to 911 services, according to Loeb.
Loeb and his co-authors used econometric models to analyze data from a number of government and private studies. He and his co-authors recommend that governments consider more aggressive policies to reduce cell phone use by both drivers and pedestrians, to reduce the number of fatalities.
词汇：
crackdown n.制裁，严惩
outweigh v.超过
fatality n.死亡者
econometric adj.计量经济的
hypothesize v.假设，假定
注释：
1. cell：cell phone 的缩写。
2. The new studies, lead-authored by Rutgers University, Newark, Economics Professor Peter D. Loeb ...第一作者为罗格斯大学纽瓦克分校的经济学教授 Peter D. Loeb 的新研究成果……lead-author：第一作者;lead-authored 为动词的过去分 词形式，具有被动意义。罗格斯大学纽瓦克分校是美国新泽西州最负盛名的文理学院。
3. critical mass：临界数量。
4. factored in：包括，把……计算在内。
5. a critical threshold：指的是前文所说的 critical mass。见注释3。
6. was canceled out：被抵消。练习：
1. The two new studies, lead-authored by Professor Peter D. Loeb
A show that talking on the phone while driving or walking in the street increases deaths of drivers and pedestrians.
B show that talking on the phone while driving increases pedestrian deaths.
C recommend that strict measures be taken to restrain cell phone use.
D both A and C.
2. According to the second paragraph, when did cell phones actually help to reduce pedestrian and traffic fatalities?
A Right after cell phones were invented.
B Before the number of cell phone users reached a critical massC When cell phone users totaled to a certain number.
D When the number of cell phones decreased to a certain number.
3. What is said about cell phone use in paragraph 4?
A The number of cell phones in use exploded in the late 1980s and part of the 1990s.
B The number of traffic deaths was reduced in the late 1980s and part of the 1990s due to cell phone use.
C Cell phone users are likely to be involved in traffic accidents.
D The use of cell phones has a life-saving effect for pedestrians and drivers.
4. What is said about cell phone use in the mid-1980s in paragraph 5?
A It had a life-taking effect because there weren't enough cell phones in use then.
B The increased use of cell phones then caused a "life-taking effect."C Traffic fatalities increased then because the number of cell phones in use decreased.
D Traffic fatalities decreased then because the number of cell phones in use increased.
5. Which of the following statements DOES NOT answer the question "What caused the "life-saving effect" to occur in the early 1990s?"
A There were more cell phone users during that period.
B The number of cell phone users reached about 100 million.
C More cell phones were used to call 911 when accidents occurred.
D Cell phones enabled people to have quick access to 911 services.
答案与题解：
1. D 根据短文第一段的内容，Loeb 教授的最新研究发现，开车或行路时打手机使司机和行 路人的死亡率上升，并建议采取严厉措施限制司机和行路人使用手机。B 是错误理解， 因为只有行路人被提到。
2. B 短文第二段最后两个句子提供了答案：在手机使用者达到 1 亿的临界点之前，手机的 使用的确减少了交通事故的死亡率。A、C 和 D 的表述内容都没有在文章中提到。
3. B A 是错误选择，因为该段的第四个句子 In the late 1980s and part of the 1990s, before the numbers of phones exploded, ...表明。手机数量在 80 年代末期和 90 年 代早期还未激增。C 的表述内容没有在文章中提到。句子…cell phone use actually had a “life-saving effect”用的是过去式，说的是发生在 80 年代末期和 90 年代早 期的事情，而 D 句用的是一般现在时，表示通常的状况，所以是错误的选择。
4. A第五段的大概意思是，80 年代中期，交通事故的死亡率增加，因为人们还在适应这一 新事物，没有足够的手机让人们在发生交通事故时及时求救。该段没有讨论 80 年代中 期手机数量的增减问题，所以 B、C 和 D 都是错误选择。
5. B第六段最后一个句子说，当手机使用者数量达到 100 万时，life-saving effect 就被 抵消了，life-saving effect 超过了手机使用者能迅速呼叫 911 服务的优点。所以，B 不是问题的答案。其他选项都表述了该段的内容。
译文
手机增加交通行人死亡
手机在路上有多种多样的危险。两个新的研究表明，不管开车还是步行时打手机，都会增加 行人、司机和乘客死亡的危险，所以该研究建议严厉限制行人和司机使用手机。
这是一项第一作者为罗格斯大学纽瓦克分校的经济学教授Peter D. Loeb的新研究成果，它把 手机的意外Ic命的影响和大量手机使用数量联系起表明目前由于手机所引起的死亡数目有所 增加，而在此之间的一段时间里，手机事实上能够帮助降低行人和交通致命率。但研究发现，当 手机使用人数达到1亿这个临界数量时，手机降低交通致命率的作用就消失了。
这些研究涉及到从1975年到2002年间的手机使用和机动车辆事故之间的关系，也涉及包括 车速、酒精消耗、安全带的使用和行驶的里数等其他方面。这些研究表明甚至当考虑比如速度、 酒精消耗和安全带的使用这些因素时，二者之间的关联也是真实存在的。
在目前，Loeb和他的合者决定手机的使用“在行人安全上有严重的反作用”并且“手机的 使用数量已经超过了临界数量也增加了机动车辆的致命性。”在20世纪80年代末和90年代的一 段时间，在手机使用数量达到大爆炸之前，手机的使用确实在交通事故中起到过“保护生命的作 用”。“当发生交通意外时，手机使用者能够快速地打电话寻求医疗帮助，这种快速的医学求救反 应确实能在一定时间内减少一定数量的事故死亡”，Loeb假设。
但是，在20世纪80年代当手机开始被使用时并不是这样，在那时手机在行人、司机和乘客 间造成了 “致命的效果。”在早些日子里，那时有不到一百万部手机，致命率增加了，Loeb说， 因为司机和行人或许在那时还在适应怎样使用它们，还没有足够的手机能够在事故中呼叫帮助， 他解释说。
这“保护生命的效果”是在20世纪90年代当大数量的手机被使用的时候出现的，越来越多 的手机在事故之后拨打“911” .求助，这就降低了致命率，Loeb解释说。但是一旦手机的使用量 超过大约一亿的“临界数量”时，这种保护生命的效果就被抵消了，而且这种“致命的效 果”——增加了事故和死亡——超过了能快速呼叫“911”服务的好处，根据Loeb所说。
Loeb和他的合著者们使用计量经济模式来分析从许多政府和私人研究中得来的数据。他和他 的合著者们都推荐政府采取强制性措施来减少司机和行人的手机使用数量，来减少死亡事件的发生。
