Can Your Smartphone Stop You from Getting Hit by a Car?智能手機能否讓你免被車撞？

安娜·布魯克斯 陶思敏 唐偉勝

Long gone are the days when we would look both ways before crossing the street. The only direction most of us look is down， ceaselessly staring into the infinite depths of our screens. Distracted walking might not seem as dangerous as distracted driving， but it could be a contributing factor in the surge of pedestrian deaths and injuries seen over the last four years， according to the Governors Highway Safety Association.

But could the very technology that distracts us also alert us to danger？ In a study published? in the journal Human Factors， a team of computer scientists tried to determine if sending warning signs to a distracted persons phone would help them safely cross a busy roadway.

“Pedestrians stand at the edge of the road， one second from death， a lot of time，” says Joseph Kearney， study co-author and professor of computer science at the University of Iowa. “Cars are whizzing by， and one single， false step could be dangerous.”

Dont worry： researchers didnt push pedestrians into a stream of oncoming traffic to test their theory. Kearney works at the Hank Virtual Environments Lab， which utilizes whats called “virtual environment technology” to study how folks cross busy streets. Wearing virtual reality glasses and head mounted displays， preoccupied participants had to navigate a 3D neighborhood while texting. If they were about to make a dangerous road crossing， a loud warning signal sounded from their phone.

Some of the results were as expected—pedestrians heeded warnings and ultimately made safer crossings. But what Kearney didnt anticipate was the participants reactions to the warning signals once they had already started crossing the road.

“The kicker was， once they made the overt motion to move， they almost never stopped and returned to the curb， even when they got a warning，” he says. “We also found they looked at the road much less when they have this alerting system. The concern is what we call ‘outsourcing our cognition—you allow the phone to make the decision for you.”

It seems counter-intuitive to keep walking if theres a speeding car coming at you， and in the study， it was. More than a third of the 300 test crossings resulted in a collision， which Kearney says was a much higher rate than other studies conducted in the simulator. In the real world， that translates to a lot of pedestrian pancakes. And even though participants knew they werent in any actual danger， Kearney says the collisions were still a shock， with many of them trying to leap out of the way of virtual vehicles.

Kearney says the instinct to keep crossing instead of turning back may have to do with whats called response inhibition， which in very basic terms suggests that its difficult to stop a motor function once it starts. Even if the alternate action—like aborting an unsafe crossing—could save your life， Kearney says very few participants instinctually did so.

For those who insist on walking and staring into the soul of your phone at the same time， dont fret too much—in the grand scheme of things， pedestrian deaths are pretty rare.

Of course， we cant blame all of this on smartphones; adverse weather， distracted drivers， and increases in numbers of people travelling by foot are just a few of many factors contributing to the rise. We dont have exact numbers on how many people are killed each year as a result of distracted walking. But thats not to say it isnt being taken seriously.

Last year， Honolulu became the first city in the U.S. to ban distracted walking. If youre caught looking at your phone while crossing the street， you could be fined up to $99. Montclair， CA quickly followed suit， doling out fines for even wearing headphones in a crosswalk. Theres a 100-foot-long phone lane at an amusement park in Chongqing， China， to prevent people from smashing into each other while walking and smartphoning—to be fair， it is pretty hard to snarf a corndog and Snapchat at the same time.

What Kearneys studying—known as V2P （vehicle-to-pedestrian） technology—already exists between cars. V2V （vehicle-to-vehicle） enables cars to communicate wirelessly to detect danger and help drivers avoid accidents. Theres already a Samsung app designed for New Yorkers called “Look Up，” which prompts distracted pedestrians to take notice when they reach an intersection. Kearney says the cellphone technology theyve been testing is ready for use， its just a matter of whether smartphone manufacturers deem it worthwhile to implement.

Neil Gaffney with the Federal Highway Administration says with pedestrians and cyclists accounting for an increasing proportion of traffic fatalities， V2P technology will “eventually be a viable solution to improve safety.” The national highway administration estimates that these new systems have the potential to prevent almost half of pedestrian crashes.

“Pedestrian detection systems can be implemented in vehicles， infrastructure， or with pedestrians themselves to provide warnings，” Gaffney says. “These include both in-vehicle systems such as blind spot and forward collision warnings， and handheld devices that can provide warnings for pedestrians. These are young， but promising applications for this developing technology.”

In the meantime， lets all look back on some long lost advice： remember to look both ways before crossing the street！

過馬路前要左顧右盼的日子早已過去了。我們大多數人看的唯一方向是朝下，無休無止地盯著那深不可測的屏幕。美國州長公路安全協會稱，走路分心看似沒有駕駛分心那么危險，但它可能是過去四年造成行人傷亡數量激增的一個因素。

但是，這種分散我們注意力的技術是否也能警示危險呢？在一篇發表在《人為因素》期刊上的研究報告中，一支計算機科學家團隊試圖確定向分心行人的手機發送預警信號能否幫他們安全穿過繁忙的行車道。

“行人站在路邊，生死只差一秒，這算是很長時間了。”該研究報告的合著者、艾奧瓦大學計算機科學教授約瑟夫·克尼說，“汽車呼嘯而過，錯一步就很危險。”

別擔心：研究人員并未將行人推向迎面而來的滾滾車流中以驗證他們的理論。克尼在漢克虛擬環境實驗室工作，該實驗室利用所謂的“虛擬環境技術”來研究人們如何穿過繁忙的街道。參與者頭戴虛擬現實眼鏡和頭顯，被要求一邊全神貫注地發短信，一邊在3D街區中穿行。一旦他們即將穿越危險的道路，手機就會發出響亮的預警信號。

一些實驗結果在意料之中——行人注意到預警，最終以更安全的方式穿過馬路。而一旦參與者已經開始過馬路，他們對預警信號的反應卻出乎克尼的預料。

“令人意外的是，一旦步伐明顯邁出，即使收到預警，他們基本也不會停下腳步并回到路邊。”他說，“我們還發現，安裝預警系統后，他們看馬路的次數少了許多。我們把這種令人擔心的情況稱為‘認知外包，即讓手機替你做決定。”

一輛疾馳的汽車朝你駛來，而你還繼續往前走，這似乎令人匪夷所思，但在這項研究中，情況就是這么不可思議。在300個測試對象中，超過三分之一的人過馬路時發生了撞車，克尼說，這個比例遠遠高于用模擬器來進行的其他研究。在現實生活中，這意味著很多行人會被軋成肉餅。克尼說，即使參與者知道沒有任何實際危險，撞車仍讓他們驚駭，許多參與者都試圖跳出虛擬車輛的車道。

克尼說，被警告后繼續過馬路而不是返回這一本能，可能與所謂的反應抑制機制有關。簡單來說，這個機制指一旦運動功能開啟，就很難停止。克尼說，即使其他行動——比如停止危險穿越馬路——可以挽救性命，也很少有參與者本能地照做。

對于那些堅持一邊走路一邊專心致志盯著手機的人來說，不必過于擔心——從宏觀角度來看，行人死亡相當罕見。

當然，我們不能把這一切都歸咎于智能手機;在導致行人死亡人數增加的眾多因素中，惡劣的天氣、分心的司機以及步行人數的增加也只是其中幾個。每年有多少人因走路分心而亡，我們沒有確切數字。但這并不意味著該問題沒有受到重視。

去年，檀香山成為美國第一個禁止走路分心的城市。如果過馬路時被發現在看手機，你可能被處以最高99美元的罰款。加州蒙特克萊迅速效仿，甚至對戴耳機走在人行橫道上的人也處以罰款。在中國重慶的一個游樂園里，有一條100英尺長的手機專用道，以防止人們走路時看手機撞到對方——平心而論，一邊大吃玉米熱狗，一邊瀏覽色拉布，如此一心二用的確很難。

克尼正在研究的技術被稱為“車輛—行人（V2P）”，該技術已被應用于汽車之間。“車輛—車輛（V2V）”技術可使汽車間進行無線通信，以監測危險并幫助司機規避事故。三星已經為紐約人設計了一款名為“抬頭看”的應用程序，當分心的行人到達十字路口，它會提醒他們注意路況。克尼表示，他們一直在測試的手機技術已經可以投入使用，關鍵在于智能手機制造商是否認為該技術值得應用。

聯邦公路局的尼爾·加夫尼表示，隨著行人和騎行者在交通死亡中所占比例越來越高，V2P技術“最終將成為一個提高道路安全的可行解決方案”。國家公路局估計，這些新系統有能力防止近一半的行人撞車事故發生。

“行人監測系統可以安裝在車輛、基礎設施或者行人自己身上以提供預警。”加夫尼說，“這些監測系統既包括車載系統，如盲點和前向碰撞預警，也包括可以為行人提供預警的手持設備。對于這項正在發展的技術來說，盡管這些系統還不成熟，但其應用前景廣闊。”

與此同時，讓我們回憶一下那條被遺忘已久的箴言：人過馬路前，記得看兩邊！

（譯者單位：江西師范大學外國語學院）

English Quotes

1. Whoever neglects learning in his youth loses the past and is dead for the future.

2. Books are the ladder in stepping up human civilization.

3. Not ignorance， but the ignorance of ignorance， is the death of knowledge.

4. Reading is to the mind what exercise is to the body.

5. Learning without thinking is cheating; thinking without learning is lazy.

6. What matters is not the idea a man holds， but the depth at which he holds it.

7. Genius does what it must， and talent does what it can.

8. Genius is the ability to put into effect what is in your mind.