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IMPORTANT UPDATE (March 30, 2012): New version is available with footer link disabled by default, and new settings page with customizable list of sites and with options for defining the scope of nofollow reciprocity. DOWNLOAD. In future new plugin versions will appear here, not on WordPress.
Because most major web-sites (many of which are build by the community) receive so much PageRank from small sites and don't give any away (by default they use 'rel="nofollow"' attribute in external links), internet is experiencing a capitalization and concentration of a PageRank which is online world equivalent to capital in the 'real' world.
Figure Explanation: Left: Good old web. Middle: Big sites nofollow small ones. Right: Small sites reciprocate.
Note that not only sites that are nofollowed (blue links) lose pagerank which is roughly represented with the size of the circle, but also other sites that are linked to from these (green links). For example, note that even though Page 1 didn't have any link from the big site 3, it did have a link from a smaller site 2 which was affected with the nofollow policy. Effectevely, the whole web is affected, including your site.
IMPORTANT NOTE: Note that since google updated the way it interprets nofollow, placing it on links will not result in the site increasing PageRank (red circle becoming bigger), but it will still result in the target site losing PageRank (blue circle becoming smaller). Read the last Q&A on the bottom of this page for further explanation.
By using nofollow, these sites do not trust external links nor users that post those links. This means that these sites don't give any credit (in the form of PageRank) to those links and are essentially considering them spam (as that was 'officially' the purpose of 'nofollow' tag introduction). This results in their pages appearing higher in search engine results and your pages appearing lower.
Another serious problem with nofollow is that it is a non standard HTML attribute value. This means that most webmasters are not aware of it, and therefore are not applying it. This means that there is no nofollow reciprocity as it is not implemented equally throughout the web. Luckily, this will change with HTML 5, when nofollow will become a part of the standard, and people will learn about it the same way they learn about other HTML elements.
<a href="http://www.example.com/" target="_blank">link with standard attribute</a>
<a href="http://www.example.com/" rel="nofollow">link with non-standard attribute value</a>
Probably every webmaster knows how to place a standard target attribute on a link. This is becuse about every single tutorial on the internet talks about it. I suggested to W3SCHOOLS.COM (one of the best HTML tutorial websites from which I learned HTML) to put a note about rel="nofollow" attribute on their HTML links page, but it seems my suggestion was ignored, even though they use the same on their right sidebar links.
We must accept reality. There are few "dofollow movements" on the internet where people suggest eliminating nofollow from blog comments (which is often o.k.), but some suggest that we should never use nofollow, which I think is not a good suggestion. Google is a major discovery tool on the internet - a gateway to world's information (and that's the only reason why I write about this -- wouldn't bother if it was some other search engine, but future is hopeful, as always), and if we want to bring back the balance to the PageRank distribution (and therefore to the access to a more diverse information in search engine results), than we have to apply 'nofollow' towards large websites that use the same. PageRank will remain a significant factor in search engine results for a while, as it proved to be a very successful tool in providing relevant results. However, pagerank distortion leads to distorted results, in my opinion, but you the reader can judge for yourself, based on (the change of?) your personal satisfaction with finding things on Google in the last three years.
Some of these sites, in addition to not giving you any credit, also DEVASTATE your site PageRank and SERP position with this nofollow monstrosity. Even such a large site like YouTube.com is defending itself from this social bookmarking PageRank leaking. YouTube, a Google company (inventor of both PageRank and nofollow) guards pagerank from "Share" social bookmarking by using rel="nofollow" to ignore the whole buttons block.
Another example is StumbleUpon that not only does not "trust" sites its users bookmark, but it does not trust links to users homepages either. Same is valid for YouTube, and most other big websites.
This plugin improves your blog PageRank and search engines rankings (search engine optimization).
However, this is much more than a search engine optimization plugin.
The purpose of Nofollow-Reciprocity is to 'redistribute' PageRank to small site owners. This plugin detects links to above mentioned sites, and puts 'nofollow' tags on them. 'Do unto others as you would have others do unto you.' WordPress is a major blogging platform, with tens of millions of users. If many people using WordPress use this plugin, other big sites may reconsider their 'nofollow' strategy. This plugin expands on Wikipedia nofollow plugin hacked by a revolted blogger.
Current sites on the list are from the list of Top 1000 sites on Quantcast.
You can easily add your own 'black list' sites in the code of the downloaded file. Note that there may be good sites on the list as I did not look at all those websites. However, almost all of the most visited sites that I looked at started using nofollow.
Download nofollow-reciprocity.zip. You can also read more about it there.
If you want to add this tags in comment author's url's whose link point to above sites, uncomment the line near the end of the code by deleting the first two slashes '//'.
//add_filter('get_comment_author_link', 'wp_nofollow_reciprocity', 999);
1. Q: The inclusion of ThisNext isn't entirely fair. While stores are "no-followed" to reduce the incentive for gaming the system, user's personal blogs and "via" attributions are left alone. You can see both on this page: http://www.thisnext.com/by/whosdiary/ [Note: this question reffered to an older version of the plugin. ThisNext.com is not in the new 'top 1000' list used in current plugin.]
A: Thanks for the note! I am not familiar with all web-sites on the list above, but have just looked quickly thru the major social web-sites. [Note: Also, most of the sites that I did take a look at from the 'top 1000' list do use nofollow. You can add or remove sites directly in the 'nofollow-reciprocity.php' file. Although you can add individual sites to this blacklist, the intention of this plugin is to create a massive effect. Instead of adding a handful of websites, consider adding many. You are welcome to send me lists of bad sites you find, or good ones that are on the current list. Eventually, we will have an ultimate list of nofollow sites.]
2. Q: Good idea, but why are you adding a link back to your own site without a nofollow?
A: This has been fixed now. Default is without a link, and you can choose to add a link, with or without nofollow attribute.
3. Q: your dofollow/nofollow articles need updating as the use of this attribute no longer allows sites to hoard page juice, instead the use of nofollow makes the potential juice evapourate so theres really no reason to use it any more as it doesnt benefit bigger sites as it once did. whether do follow is there or not the site would have the same juice flowing internally. just thought you should know.
A: While nofollow doesn't benefit bigger sites the way it used to, big sites still use it, and therefore still don't give benefit to small sites. Nofollow Reciprocity does the same to big sites. It doens't bennefit *directly* small sites through juice preservation, but it does bennefit small sites *indirectly* by decreasing the amount of juice big sites get, and therefore lowering their rankings (which allows more small sites to compete with them).
© 2008, Nofollow by Lazar
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