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
76
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://www.kaotiyun.com/show/qHYO777K
0
专业英语八级
相关试题推荐
Inthe1960spopmusicunderwentarevolutionwhen______becameworldfamousandturnedtheirhometownofLiverpoolintoaplac
ManyAdecadeago,atatimewhenplaceslikeIvoryCoastandEquatorialGuineawerebeinglargelyignoredbythepetroleumworl
Onethingthatdistinguishestheonlineworldfromtherealoneisthatitisveryeasytofindthings.TofindacopyofTheEc
Onethingthatdistinguishestheonlineworldfromtherealoneisthatitisveryeasytofindthings.TofindacopyofTheEc
FredCookeofSalfordturned90twodaysagoandtheworldhasbeenbeatingapathtohisdoor.Ifyouhaven’tnoticed,theback
A、Goonlineandwaitforthedeliveryofthebookordered.B、Checkthelibrary’swebsiteandthengotothelibrary.C、Goonline
A、theysufferfromamnesia.B、theyarenotorganized.C、theyhavetoomanythings.D、theyareofteninahurry.B
A、getatmorespecificthings.B、getatmoregeneralthings.C、getatmorepersonalthings.D、getatmorepublicthings.A
Behindthebrewingwaroverprotectingpatients’recordsinanageofHMOsandonlinemedicine.Technologyisatwo-edgedswor
随机试题
资本主义国家如何利用利率调节经济?
综合课的结构一般包括,(),(),(),(),()。
红斑狼疮急性期,水肿性红斑。治宜:DLE陈旧性盘状浸润斑块,覆较厚鳞屑痂皮。治宜:
患者,男性,36岁。上腹部疼痛伴恶心、呕吐4小时入院。5小时前进食晚餐(红烧肉、排骨、白酒等),1小时后突发腹痛,以上腹部为主,胀痛性质,持续发作,半蹲位稍可缓解,伴恶心、呕吐,无腹泻。提示:体查:体温38.5℃,心率120次/分,呼吸25次/分,血压10
中国某公司与美国某外贸商签订进口一套发电机的买卖合同,合同约定价格条件为FCAINCOTERMS2000。依此价格条件,以下表述不正确的是:
某零件年需要量16200件,日供应量60件,一次订货成本25元,单位储存成本1元/年。假设一年为360天,需求是均匀的,不设置保险库存并且按照经济订货量进货。要求:计算与订货批量有关的总成本。
已采用公允价值模式计量的投资性房地产,如果不能持续取得该房地产的公允价值时,应当将其转为成本模式计量。()
根据以下资料,回答下列问题。(注:顺差是指在国际收支上,一定时期内收入大于支出的差额;逆差指的是在国际收支上,一定时期内支出大于收入的差额;表中同比数据为正的代表同比增长,同比数据为负的代表同比下降)2016年个人、文化和娱乐服务进口额占同期服
Doanimalshavefights?Thisishowthequestionisusuallyput.Itseemsauseful,ground-clearingwaytostart.【61】Actually,
A、Peoplearehighupinthesky.B、Itisnotanaturalwayoftransport.C、Theflyingspeedisveryfast.D、Peoplehavetostay
最新回复
(
0
)