首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
One thing that distinguishes the online world from the real one is that it is very easy to find things. To find a copy of The Ec
One thing that distinguishes the online world from the real one is that it is very easy to find things. To find a copy of The Ec
admin
2011-03-10
52
问题
One thing that distinguishes the online world from the real one is that it is very easy to find things. To find a copy of The Economist in print, one has to go to a news-stand, which may or may not carry it. Finding it online, though, is a different proposition. Just go to Google, type in "economist" and you will be instantly directed to economist.com. Though it is difficult to remember now, this was not always the case. Indeed, until Google, now the world’s most popular search engine, came on to the scene in September 1998, it was not the case at all. As in the physical world, searching online was a hit-or-miss affair.
Google was vastly better than anything that had come before: so much better, in fact, that it changed the way many people use the web. Almost overnight, it made the web far more useful, particularly for non- specialist users, many of whom now regard Google as the internet’s front door. The recent fuss over Google’s stock market flotation obscures its far wider social significance: few technologies, after all, are so influential that their names become used as verbs.
Google began in 1998 as an academic research project by Sergey Brin and Lawrence Page, who were then graduate students at Stanford University in Palo Alto, California. It was not the first search engine, of course. Existing search engines were able to scan or "crawl" a large portion of the web, build an index, and then find pages that matched particular words. But they were less good at presenting those pages, which might number in the hundreds of thousands, in a useful way.
Mr Brin’s and Mr Page’s accomplishment was to devise a way to sort the results by determining which pages were likely to be most relevant. They did so using a mathematical recipe, or algorithm, called PageRank. This algorithm is at the heart of Google’s success, distinguishing it from all previous search engines and accounting for its apparently magical ability to find the most useful web pages.
Untangling the web
PageRank works by analysing the structure of the web itself. Each of its billions of pages can link to other pages, and can also, in turn, be linked to. Mr Brin and Mr Page reasoned that if a page was linked to many other pages, it was likely to be important. Furthermore, if the pages that linked to a page were important, then that page was even. more likely to be important. There is, of course, an inherent circularity to this formula—the importance of one page depends on the importance of pages that link to it, the importance of which depends in turn on the importance of pages that link to them. But using some mathematical tricks, this circularity can be resolved, and each page can be given a score that reflects its importance.
The simplest way to calculate the score for each page is to perform a repeating or "iterative" calculation I see article). To start with, all pages are given the same score. Then each link from one page to another is counted as a "vote" for the destination page. Each page’s score is recalculated by adding up the contribution from each incoming link, which is simply the score of the linking page divided by the number of outgoing links on that page. (Each page’s score is thus shared out among the pages it links to.)
Once all the scores have been recalculated, the process is repeated using the new scores, until the scores settle down and stop changing (in mathematical jargon, the calculation "converges". The final scores can then be used to rank search results: pages that match a particular set of search terms are displayed in order of. descending score, so that the page deemed most important appears at the top of the list.
Which of the following is NOT true?
选项
A、Each page can be given a score that reflects its importance.
B、In the beginning of rating a page’s relative importance, all pages are given the same score.
C、The importance of one page depends on the importance of pages that link to it, the importance of which depends in turn on the importance of pages that link to them.
D、One page’s score is given totally to another page it links to.
答案
D
解析
关于Google的搜索规则设置,是最后几段的内容,稍微专业了一些,但一些基本的规则还是比较明确的。首先每个网页都有一个相同的标分,每一网页的标分平摊到它所连接的网页上。
转载请注明原文地址:https://kaotiyun.com/show/qHYO777K
0
专业英语八级
相关试题推荐
Inthe1960spopmusicunderwentarevolutionwhen______becameworldfamousandturnedtheirhometownofLiverpoolintoaplac
ManyAdecadeago,atatimewhenplaceslikeIvoryCoastandEquatorialGuineawerebeinglargelyignoredbythepetroleumworl
Onethingthatdistinguishestheonlineworldfromtherealoneisthatitisveryeasytofindthings.TofindacopyofTheEc
FredCookeofSalfordturned90twodaysagoandtheworldhasbeenbeatingapathtohisdoor.Ifyouhaven’tnoticed,theback
A、theysufferfromamnesia.B、theyarenotorganized.C、theyhavetoomanythings.D、theyareofteninahurry.B
Mentalhealthprofessionalmaybesurprisedtodiscoverhowmuchishappeningonlinetodayinthehealthcarefield.Workingclos
Mentalhealthprofessionalmaybesurprisedtodiscoverhowmuchishappeningonlinetodayinthehealthcarefield.Workingclos
A、Aplacethatsellssesame.B、Aplacefamiliartochildren.C、Aplacewithallkindsoffunnythings.D、Aplacewecangetless
A、Goonlineandwaitforthedeliveryofthebookordered.B、Checkthelibrary’swebsiteandthengotothelibrary.C、Goonline
随机试题
乙醇消毒常用的浓度为
患者,男,40岁。间断颜面及下肢水肿2年,晨起时明显,双下肢轻度水肿,尿少,乏力,无恶心、呕吐、黄疸,既往体健。BP:150/90mini-Ig,24小时尿蛋白定量:887.6mg。血常规:Hb101g/L。尿常规:尿蛋白(++),RBC10~24/H
在砌体结构的静力计算中,横墙中开有洞口时,洞口的水平截面面积不应超过墙横截面面积的()。
“备案号”栏应填()。“净重”栏应填()。
甲企业于2012年1月1日发行2000万美元债券,票面利率5%,为期3年,年初付息。2012年1月1日开始购建固定资产,2013年6月30日购建完毕。2012年1月1日汇率6.30,2012年12月31日汇率6.29,2013年1月1日汇率6.28,201
甲公司向乙银行借款,并以其所持有的某上市公司的股权设立质押。根据《物权法》的规定,该质权设立的时间是()。
下列各选项中,不属于国际储备的是()。
骑车人以每分钟300米的速度,从电车始发站出发,沿其线路行进。骑车人离开始发站2100米时,一辆电车驶出始发站,这辆电车每分钟行500米,每5分钟到达一站并停车1分钟。多少分钟后,电车追上骑车人?
下列表述错误的是()。
Manypeoplewronglybelievethatwhenpeoplereacholdage,theirfamiliesplacetheminnursinghomes.Theyareleftinthe【C1】
最新回复
(
0
)