Alexa ranking mechanism-alexa world rankings

Prerequisite
1, alexa site ranking is based on the number of visits to each specific site ranked. The greater the number of visits, the higher the rank.
2, the amount of traffic is defined on the domain site for statistics. such as: www.sina.com.cn, news.sina.com.cn and tech. Sina.com.cn will be counted as the same Web site because they belong to the sina.com.cn domain. Except for personal homepage, if the system can automatically distinguish from the URL address, it will be considered as a separate site. For example: in Silu (http://www.xilu.com/) to apply for myweb.xilu.com and hisweb.xilu.com two different personal home page space, myweb.xilu.com, Hisweb.xilu.com and www.xilu.com will be counted as three separate Web sites, rather than as part of a unified count in the xilu.com domain.
3. Sites that provide the same content will be counted as the same site. For example, the Communication Research network uses www.mediaresearch.com.cn and http://www.mediaresearch.cn/two domain names to publish the same content, and will be counted as the same Web site.
4. The amount of traffic included in statistics comes only from users using the Alexa toolbar (Alexa Toolbar). That is, only users download the Alexa toolbar and embed it in their browser. In this way, the user accesses a Web site, and the records they visit can count as the number of visits to the site. According to Alexa statistics, the user now uses the toolbar up to millions of.
5, the Alexa toolbar only under the Windows operating system, the Internet Exploer browser, the use of other operating systems or browser access will not be counted.
6, encounter a security or encrypted site (such as using HTTPS protocol), Alexa toolbar will automatically shut down, so those high safety factors of the site, Alexa will not be able to search and statistics rankings.
Traffic algorithm
1, a specific Web site is ranked, based on the amount of traffic data base on the site's 3-month traffic records accumulated. That is, Alexa every three months to publish a ranking results, that is usually said ranking. Its calculations depend primarily on the number of user links (users reach) and page views. The Alexa system every day to each website user link number and the page browsing number carries on the statistics, through these two quantities three months cumulative value geometric average obtains the current rank. Change refers to the comparison with the previous three months.
2. Number of user links (users reach) refers to the number of people accessing a particular Web site over the Internet. Represents the proportion of people who access a particular Web site to the number of Internet users.
That is: The number of user links = (number of visitors/all Alexa users) * 100%,alexa per million people as the count unit. Take Yahoo, for example, if its user link number is 28%, that is, 1 million Internet users are randomly selected, 280000 of whom visit Yahoo.