PageRank, page level
Google search engine using the core software known as PageRank, this is the founder of Google to develop a set of Web rating system, is a Google search ranking algorithm is an integral part of the level from 1 ~10 level, 10 grade for full marks, The higher the PR value indicates the more important the page's position in the search rankings, that is, in other conditions, the PR-high site has priority in the rankings of Google search results. Web pages do not form the basis for all of Google's Web search tools.
1. Web page Level overview
When you link to page b from page A, Google thinks that "page A has voted for B". Google evaluates its importance based on the number of votes in the Web page. However, in addition to considering the sheer number of votes (i.e. links) on a Web page, Google has to analyze the voting pages. The "important" pages will have a higher weighting on the votes and help improve the "importance" of other pages. Important, high-quality Web pages will get a higher level of web pages. When Google arranges its search results, it takes into account the level of each page. Of course, if you can't meet the user's query requirements, the high level of Web page is meaningless. As a result, Google combines page levels with sophisticated text-matching techniques to find the most important and useful pages for users. Google's focus is much more than the number of keywords that appear on the page, and it also checks the content of the page (and the content it links to) to see if the page meets the user's query requirements.
Principle of 2.PR value algorithm
(1) If a page is referenced multiple times, it may be important; A Web page is referenced by important web pages, although it is not referenced multiple times. It may also be important; the importance of a Web page is passed on to the Web page it refers to. This important web page is called the authoritative page.
(2) Assuming that the user first randomly access a page in the collection of pages, and then follow the link to the page to browse the page, not back to browse, then the probability of browsing the next page is the PageRank value of the page.
3. Factors affecting the PR value
The PR value is embodied in 11 values from 0~10. Due to the Google market expansion process, the PR value of Chinese web pages as a whole is lower than the English page. For the Chinese site, with 3-level PR is the basis, 4-level PR to achieve standards, 5-level PR is good, and 6-level, 7-level PR even quite excellent site. Of course, because the most direct impact of PR is from the link, so this rating does not represent the level of content, site content quality of the impact of the PR is indirect, long-term. According to the PR value of the algorithm principle, we know that the impact of a website (home) PR value of the main factors include:
1 The quality of the website's import link
According to the previous analysis of the high quality import link, the high PR value needs to obtain the link from the following websites:
(1) to join the search engine classification directory.
(2) with the added directory of the site exchange links. Www.111cn.net
(3) Obtain a link from the PR value not low dry 4 and related or complementary to your subject site.
(4) Link out of the current flow of large, high-profile, frequent updates on important sites (such as news sources).
(5) The exchange link of the other site has very few export links.
(6) With the content of high quality site links (pr value rising potential).
2) Export the number of links
According to the principle of PR calculation, because "the importance of a Web page is passed to the quoted page", so in turn, too many export links within a page will potentially cause the loss of the PR value of the page. However, from the content point of view, the appropriate number of linked to the topic of the export links to the search engine to bring a good impression. Therefore, a page, especially the number of export links to the master, should take into account the PR value and keyword content between the two balance, that is, control the number of export links, to no more than 10.
3 search engine contains a site number of pages
In the discussion of SEO, people will pay too much attention to the core keyword rankings and the performance of the home page, but often overlooked an extremely important problem, that is, search engine on a site included in the number of pages. The latter also has extremely important significance in the SEO. A key keyword Query rankings poor site, may be crawled by a large number of pages and users use other keyword queries, the page to get the top three rankings. Because the user searches uses the keyword to have the dispersibility, causes this kind of situation often to bring the level big visit quantity to the website.
Because the number of pages directly affect the amount of access, so the impact on the PR value is also very large. The more pages are included, the higher the homepage pr. What needs to be emphasized is: the number referred to here refers to the ratio of the number of pages collected and the total number of sites, rather than the absolute value of the pages included. For example, a site with 50 pages is included in 10 pages, the site is included in the ratio is 1/5, a 5,000-page site has been included in 500 pages, the ratio is 1/10, the result is a collection of 10 pages than 500 pages of the site also has a more ranked advantage. But for each search engine, how far to achieve the ratio is good, there is no relevant data.
4) The high and low PR of the homepage
Although the definition of PR is for the Web page rather than the site, but because each page relies on a site, the homepage is the core of the promotion of the page, so the home page PR high and low on the pages of the PR also have a direct impact. Generally speaking, the PR value of each page of a website presents the following trend: Home > Level page > Level two page > Level three page ... Each depth level, PR lower 1~2 a grade. A deeper level may not be included in the rating range. Of course, if a deep inner page has many external or internal links, the situation is different. Www.111cn.net
5) file type
The Web pages and file types that Google can index include: PDF, asp,jsp,hdml,shtml,xml,sfm,doc,xls,pptrtf,wks,lwp,wri,swf. Documents made in PDF format are often important content or articles of the website. So Google's default PDF file PR value defaults to 3, higher than the normal HTML file. Similarly, Google gives XML, PS, Word, PowerPoint, Excel, and other types of pages of the PR is also higher than ordinary Web files. Therefore, for the site more valuable content, the proposal is made in PDF format.
6) PR value of the update
Google makes a thorough data update every month (dance), updated site rankings and import links will have some changes, but its PR update time is generally delayed to complete data update after three months or so, and the site's PR value is relatively stable, to rise or fall a level of PR is not easy thing.
The role of 4.PR values
Because the level of the Web page is directly affected by the link, and the external link is only one aspect of SEO, so the level of PR can only reflect the SEO part of the effect. A Web page with a high PR value can be explained only by:
(1) The homepage is more important, has the priority before the rank, and cannot draw the equal sign directly before the rank.
(2) have the advantage of negotiating high quality import links.
(3) Search engine will speed up the updating of Web page data. Www.111cn.net
Because of the ranking by the priority and negotiation advantages, so that high PR value of the site is often ultimately a high ranking, many people in the industry will simply direct the PR directly with the SEO equals, this is not only incorrect, but also unfavorable to the thousand SEO implementation. Because the PR value is not high site is also likely to get good rankings, and the PR value of high does not necessarily have the ideal ranking. And, under the guidance of such thought, people often one-sided pursuit of link effect, ignoring the SEO for content, structure, keywords and other aspects of the analysis and improvement, and the latter is the user and search engine long-term focus. ~