Step 6 - Link Popularity Analysis

What is link popularity?

Link popularity is a measure of how many websites are pointing hyperlinks at another website. A hyperlink is an HTML tag element that is able to take a user from site-to-site or from page-to-page.
When a hyperlink is displayed in an HTML document, it turns into blue colored text that can be clicked on like this sample link below pointing to  www.anotherdomain.com:

This is a link to another domain

Hyperlinks also serve a very special purpose for the search engines. A hyperlink is made up of two main parts. The target URL and the clickable link text, or anchor text. The target URL above is highlighted in green (<a href="http://www.anotherdomain.com">) and the anchor text ( This is a link to another domain ) is highlighted in yellow. The anchor text tells the search engines a great deal about the website where the link is pointing to. For now, just remember the anchor text is a very important part of successful link building.

Here is a brief illustration below of how the search engines may see a few golf related websites linked together.

The search engines' view of hyper links.

The Web by its very nature is based on hyperlinks where sites link to other sites. Each site linking to another site is in fact casting a vote in favor of the sites they link to. Since search engines can organize and count these links in their vast databases, they are able to determine which sites get more inbound links related to specific search topics. However, the search engines go way beyond just simply counting links. Just imagine how easy it would be to get top ranking based on link quantity alone. The search engines combine the ranking scores of on-page factors and the link popularity scores to come up with a final ranking order in response to user queries. While it is still possible to achieve high rankings for moderately competitive terms without a great deal of link popularity, it is unlikely your site will ever rank well for very popular terms without it.

Every inbound link is considered a citation for a particular website. In turn, every citation is interpreted as a recommendation for a site's quality by the search engines. The more citations the search engines can find, the more trusted a site becomes through the power of links. Most of the major crawler based search engines: Google, Yahoo!, and MSN employ some type of link analysis as part of their ranking algorithms and can easily discover newly created links on any site pointing somewhere else.

The benefits of link popularity

Link Popularity is one of the most important and critical aspects of any effective search engine optimization campaign today. Link popularity is the most important off-page factors to consider improving for all websites. The key concept to understand about link building is, you don't need thousands of links to successfully compete, you just need the links that are the most related to your site with the highest quality possible.

In other words, it's not just about getting lots of links from  instead, you want links from high quality web pages that are topically relevant to your website with the target keywords inserted into the anchor text of the inbound links. Please refer to this handy checklist below to analyze the backlinks of your competitor's websites and your own.

Off-Page ranking factor checklist

Understanding the Google PageRank

Fighting spam, and running a trusted search engine used daily by millions of users is not an easy job. Google understood this very well even in their early days. The Google's Page Rank was born in the minds of its founders, Larry Page and Sergey Brin at Stanford University. The Google PageRank simply put is the measure of a website's external and internal links on a logarithmic scale, also known as PR. The Google PageRank is the foundation for Google's link popularity calculations.

The Google PageRank scale starts at zero for brand new sites and it can reach a maximum of ten for well established sites with thousands of inbound links. Only a handful of sites can ever reach a PageRank of ten, for example, Google and Adobe have a PageRank of ten with a handful of other sites. An average website will normally have a PageRank of between 4 and 6. The more popular websites will have a PageRank of 7 or higher. As an example MSN and Yahoo! both have a PageRank of 9. Google PageRank is used to assign a value to the importance of every web page on the internet. To arrive at this value Google measures the links pointing to your website found on other web pages. Links from each site linking in counts as a 'vote' for your site. 'Votes' from sites with a higher page rank are weighed more than votes from sites with a lower page rank or no PageRank at all. Also, pages with a lot of links on them will pass a lot lower page rank value to the target page than link pages that have only a handful of external links. So acquiring links to your site from other websites is an important strategy for achieving a high PageRank value and ultimately a higher search engine ranking with Google.

The PageRank correlates to the number of inbound links to a site, but it's not a linear relationship. The pure number of inbound links can't be compared alone. For example two websites reporting identical number of inbound links could have different PageRank values due to the variance of PageRank of individual back links. It suffices to say, the number of backward links are a very important measure of a website's ability to compete in the natural search results. The Google PageRank and the anchor text in incoming links play a major role in your sites ranking in the search engine results pages (SERP).

A higher Google PageRank also delivers some other benefits. One of them is the increased spider visits by the search engines, which will guarantee freshness of your web pages in the search results and likely more pages indexed as well.

Download and install the Google Toolbar

The Google Toolbar is one of the most widely used tools by search engine optimizers and it can provide invaluable information about any website's popularity on the Internet. It also comes with some very handy web browser utilities, including pop-up blocking and automatic web form filling.

The Google toolbar as displayed in Internet Explorer

The Google toolbar is available for Internet Explorer version 5.5 and higher. A newly released FireFox compatible Google toolbar is also available.  

The most important feature of the Google Toolbar is the Google PageRank gauge. You may have to enable it in the options menu if it's not visible on the toolbar. The PageRank gauge is displayed on every page you visit in the middle of the toolbar as a green bar like this . When you move your mouse over the toolbar, the PageRank displays a number between 0-10 called the Google PageRank. Simply put, the PageRank helps Google determine the importance of a web page. The Google PageRank constantly fluctuates internally and it's a floating point calculation. This means when you see a value of 4, for example on the toolbar, it can be any value between 3.5 and 4. The Google toolbar PageRank public interface is normally updated only about 3-4 times a year.

Checking backward links

Another important feature of the Google toolbar is the "Backward Links" search, which is displayed as a menu option directly below the Google PageRank like this:.

The Google Toolbar "Backward Links" search feature

One important thing to note about the Google Toolbar "Backward Links" checking feature is that it will only display a filtered set of inbound links to a website, and it's not a reliable way to determine the true number of inbound links. According to some SEO professionals, Google only displays inbound links from pages that have a minimum of PageRank 4, but this can't be reliably confirmed. The reason for Google's continued secrecy about the true number of backlinks is to keep webmasters guessing about how top rankings are achieved. So please don't use Google as the sole means of checking inbound links for your own site or your competitors as it's highly unreliable.

Luckily, Yahoo! is a very trustworthy source of inbound link checking and they even have a set of Site Explorer tools for webmasters to use for free. SEO Studio also has a built in capability to check inbound links using the Yahoo! API to any website. Using the Yahoo! API ensures your IP address will not be banned for running a larger number of link checking queries. The Links Plus+ tool's link popularity checking features goes way beyond the Yahoo! Site Explorer's linking data. We'll cover in detail later how to use the SEO Studio link analysis tools to your maximum benefit.

A better SEO toolbar for FireFox

Aaron Wall, a well know and respected author of SEO Book and many industry articles has released a free Firefox based SEO tool called SEO Firefox. The SEO Firefox extension gathers a wealth of information about link popularity and many other off-page factors under the listing of each search result. It's a very convenient ad-hoc tool to complete a quick off-page analysis on top ranking competitors without leaving your web browser.

Proper Google PageRank distribution through internal links

Internal linking techniques and outbound links originating from your site can play a big role in how well your site will rank. Internal and external linking can also affect the Google PageRank value of your home page and internal pages.

The rule of thumb to follow for all sites is to ensure the footer, header or side navigation contains links back to the important pages of the website from every page. This can be accomplished with the use of some type of search engine friendly menu system. To further simplify the maintenance of adding and removing menu items, the use HTML server side includes or server side scripting languages like ASP, PHP, CGI or .NET is highly recommended. A well interlinked website is not only great for search engine ranking, but it also increases your site's usability.

Let's illustrate a well laid out website that is heavily interlinked:

Beyond the basic steps of directing the Google PageRank to your main pages, you may also want to protect your site from "leaking" valuable PageRank to other pages on your site that are not as important to rank well, but still need to be found by your visitors. We are referring to privacy policy, or terms of service pages and many other non search engine relevant pages. In these cases, you may want to use the "nofollow" link attribute as illustrated below in the links. The nofollow link attribute tells the search engines the link does not pass any link reputation or Google PageRank value to the target page whether it's an internal or external page. All major search engines respect the nofollow link attribute.

An example of using the "rel=nofollow" attribute:

The "nofollow" links will function as normal links. There will be no noticeable difference to the website user. The search engines, however, will take note of the attribute and will not pass link reputation or Google PageRank to external or internal pages. The benefit of this approach is being able to control and channel the Google PageRank throughout the site to our advantage without leaking valuable PageRank to internal or external pages we don't want link reputation to flow to.

Another popular option to preserve the Google PageRank is to link to less important pages on your site using JavaScript based dynamic links. These types of links pass no PageRank value since the search engines can't follow them. It's important to note that JavaScript executes in the browser window of the website visitor. Since the search engine spiders don't open browser windows, dynamic links are not followed by the engines. Here is an example of a dynamic link not followed by the search engines.

An example of using a dynamic JavaScript based link:

How can external links lift your sites ranking?

Grasping the concept of link popularity for novice web masters can be fairly complex. Link popularity can be expressed in rather simple terms of links equal votes. Just like in a democratic election, votes are cast for the favorite candidates. As a webmaster, you want to make sure your website becomes a favorite site to link to by others site within your topic because it has some value to offer. Your ongoing job as a webmaster will be to make a quality site and seek inbound links from as many related sites as you can.

Let's illustrate the linking of sites on the web, and the ranking factors behind each incoming link. As you look at this diagram, you will notice how the Google PageRank from high PR sites pushes the Google PageRank value of our own imaginary site to PR6. Each incoming links to our site will pass a certain amount of its PageRank to our home page increasing its own PageRank. For the purposes of this illustration, we'll assume the inbound links are coming from sites which don't use the "nofollow" link attribute or dynamic linking and therefore pass the full PageRank value to us.

Sites linking to us with high a PageRank value are contributing a higher PageRank than sites that have a lower PageRank of only 1 or 2. The sites linking to us with a PageRank of zero still could be valuable provided they are indexed by Google and are closely related to our topic.

An illustration of Passing the Google PageRank.

Beyond the PageRank value being passed to us, we are also receiving direct votes for our site from those external pages, increasing our site's overall link popularity.

Although each link can be a valuable vote for us, the real question is:
 

• Do the websites linking in have a similar keyword theme to our site?

• Do the link pages contain relevant title tags, body text and internal links to our site?

• How many other links are present on those link pages linking to us?

• What is the Google PageRank of the site and link page linking to us?

• Are the linking in sites considered an authority on the subject matter?

The search engines definitively notice these seemingly subtle differences, and therefore you should also ensure you only request links from relevant sites with the same keywords in their titles, web pages and internal links. In the upcoming lessons well be discussing the most effective techniques to acquire links, and the various ways of requesting links from other webmaster. You'll also learn about specific inbound link formatting options that can make or break your link building campaign.

Link manipulation and the rise of link spam

The reason search engines develop and continually tweak their link popularity algorithm is to minimize the effect of unscrupulous web masters who might use spamming techniques to help their sites rank higher. The manipulation of inbound links by webmasters to gain commercial advantage continues to be the biggest challenge for the search engine to tame and control. Link analysis gives search engines a new way of determining which pages are more relevant for particular topics or query phrases. Google even defines and warns webmasters against using link schemes in their webmaster guidelines. There is a very good description of what links spam is and how the search engines deal with link popularity manipulation in a university research paper titled SpamRank Fully Automatic Link Spam Detection (PDF Document Link).

Here are the most popular link spamming techniques:

• Guest book spam. Guest books used to be very popular a few years ago. Guest books allowed visitors to leave comments and feedback, but soon dishonest marketers started using guest book forms to submit unrelated and unwanted links. Although the number of guest books is on the decline due to other user generated content options emerging, guest books are still exploited today by link spammers for gaining link popularity and Google PageRank.

• Blog comment and Trackback spam. This link schemes involves some type of automated tool or script that inject promotional links into other people's blogs who are unaware of the available comment protection methods such as captchas which presents a small image for human verification. The spammers always look for the path to least resistance and search out vulnerable blogs running older versions of Wordpress and other blogging scripts that automatically approve blog comments. The search engines recommended webmaster to use the "no-follow" link attribute tag in all blog comments posted by users to avoid passing link reputation and the Google PageRank to sites that had not been reviewed by the blog owner.

• Forum post and forum profile spam. Not much different from blog comment spam, forum posts are generated by automated scripts as well and look for loopholes in popular forum softwares such as PHPpbb and other open sources forum packages. The automated scripts can create a fake user IDs on forums and start making forum posts laden with spammy links within minutes. Because forums don't use the "no-follow" link attribute, the spammers prefer to post to forums or create profiles with self serving promotional links.

• Cross linking. Cross linking involves creating a network of unique domains for the purpose of manipulating link popularity and the Google PageRank. The spammers heavily interlink the sites to distribute link popularity and PageRank among all the participating domains. Most often than not, all the websites are hosted on the same server, which makes the detection of this type of linking scheme very easy to identify by the search engines.

Who do you trust?

Let us introduce you to a new term called "TrustRank." TrustRank is Google's refinement of the purely PageRank driven algorithm which doesn't take into consideration a website's quality and authority. The Google PageRank is strictly driven by the number of inbound links, and the PageRank distribution of the links flowing between the pages from external and internal sources. The PageRank doesn't care about topical relevance or whether or not the site contains any useful information. While the Google PageRank could help evaluate web pages' importance globally, it was ill equipped to deal with spam and PageRank manipulation in specific market segments. For example, the insurance and financial sectors are notorious for attracting the most spammers, but we could list a number of other niches, such as cell phone ring tones, mp3 download site and many others.

In order to combat web spam, Google introduced a new algorithm called Trustrank in a research paper titled "Combating Web Spam with TrustRank." Essentially TrustRank gives higher ranking scores to sites that get links from high quality "seed" websites that are considered an authority on a specific subject matter.

Here is how the Stanford research paper defines the inner workings of TrustRank:

"The algorithm first selects a small seed set of pages whose "spam status" needs to be determined. A human expert then examines the seed pages, and tells the algorithm if they are spam (bad pages) or not (good pages). Finally, the algorithm identifies other pages that are likely to be good based on their connectivity with the good seed pages."

What does this mean for your site? Getting links directly from topically relevant sites considered "seed" sites or links from sites who have links from "seed" sites is the key to higher ranking. The "seed" sites are also referred to as authority sites or hubs. You can find hubs by searching for sites that provide links to many top ranking sites. Fore example if you wanted to find the best authority sites, you would do a search for the top 10 sites and than looking at their backlinks, you would find which backlinks they have in common. The top sites most likely have links from the DMOZ and Yahoo! directories and a few other industry specific organizations, blogs or forums.  

You can speed up the manual link analysis process a great deal with the help of a fantastic online tool called the HubFinder created by SEOBook.com. Just enter your keyword phrase and select the number of top ranking sites to check and the minimum number of matches for sites linking in. Start with a lower number of minimum matches to make sure you don't miss any important sites to consider getting links from.

The magic of the link anchor text

Every one of the above off-page factors are very important, but probably none of these factors have as much influence on your search engine ranking as the inbound link anchor text. Since the search engines can only understand links in terms of the clickable link text it crucial to ask your link partners for very specific link text formatting with your keywords in the inbound links.

Here are the most affective tips for inbound link anchor text selection and formatting using a website selling golf shoes as an example.

• Request your keywords to be inserted into the linking text, but vary the anchor text of the keywords. Pay special attention to how many times you request the same keywords to be used in the inbound link text by your link partners. If every one of your inbound links will look like the one below, the search engines will suspect there is some unnatural link building happening to the site. They may discount the value of other links with the same anchor text, or they may penalize your site for other related terms as well.
  
  Below is a sample link pointing to the home page targeting the main keyword phrase "golf shoes":

  <a href="www.greatgolfshoes.com/">Home of Great Golf Shoes</a>

   
  
  The resulting link will look like this Home of Great Golf Shoes

   

• Request some of the inbound links to point to sub pages of your site with anchor text that matches the title tag of the target page. Ask for some of your links to be pointed to internal pages like the illustration below targeting a different keyword phrase. This type of linking is also referred to as "deep linking. Ensure, you point at least 30%40% of all links to the sub pages of your site with the appropriate target keywords that match some of the keywords in the target page title.
  
  A "deep link" pointing to a sub page of the greatgolfshoes.com domain targeting the secondary phrase "nike golf shoes":

 
The resulting link will look like this Nike Golf Shoes
 

Changing the anchor text in the inbound links and pointing links to sub pages accomplishes two things:

• A large number of links to sub pages suggests to the search engines your site has a wealth of information to offer its visitors and should be considered a serious resource. A shallow inbound linking structure and nearly identical anchor text in the majority of inbound links to the home page is a clear sign of link manipulation by the search engines. The most likely penalty will be an almost non existent ranking for the target keywords most often found in the inbound anchor text.

• Secondly, getting high ranking for secondary keyword phrases can't be accomplished easily without inbound links to sub pages targeting secondary key phrases no matter how well you optimize those pages. If the inner pages are not receiving any direct inbound links, they will most likely not rank well for highly competitive keyword terms. Although they may rank for some obscure low search volume keywords.

"Off-page" analysis example

Before we start up the SEO Studio Links Plus+ tool, we wanted to ensure you fully understand how link analysis works by directly checking the search engines for backlinks.

Here is a brief list of the major search engines and their "backlink" checking search commands to find inbound links to a particular domain. Try the commands out on each search engines and observe the results and more importantly the differences. Have you noticed the number of links from Google is grossly under reported? We have warned you about this, so please use Yahoo! for link analysis instead.

Entering the domain name with the "www" prefix or without it could have big difference in the number of backlinks reported.
In the next lesson we'll discuss the ways you can ensure that all your links are pointing consistently to the "www" prefixed version of your domain to insure your site is not "splitting" the Google PageRank and its link popularity strength.

1. Open the Links Plus+ tool

Enter the website address you want to find the inbound links to and enter a keyword phase you want to use in the keyword analysis of the link pages. The second option comes very handy if you want to retrieve the page titles and META tags of inbound links and perform a deep analysis on them.

The SEO Studio Links Plus+ tool configuration screen for retrieving inbound links to Thepartsbin.com

Select the Yahoo! search API to perform the inbound links search. Please note you will need to request your own Yahoo! developer API key from Yahoo! to use this feature. In addition to the Yahoo! API inbound link checking, you can also use other engines such as Google, or Hotbot, but we recommend the Yahoo! API due to safe and legal link checking that doesn't jeopardize your PC's IP address being blocked.

Selecting the search engines for the "backlink" check in Links Plus.

Select the inbound link analysis data shown below in the Advanced options window. These options will give us a good idea about the thepartsbins.com's linking strategy. Please note, we have decided to exclude duplicate links and internal links to clean up the search results prior to reviewing the links. This will help us to comb through the links much faster.

When you have selected the options below, hit the Start button to start the inbound link retrieval process to thepartsbin.com website.

Selecting advanced options in Links Plus.

In the links search results screen below, you will see a handful of links retrieved from Yahoo!. The Links Plus+ tool can retrieve hundreds of links and analyze them quickly. We can clearly see this site is targeting "import car parts" as one of their main keywords in addition to their own website name and a few other keyword terms.

Please take note of the different anchor texts used in the linking text to this site. As we have discussed in the previous section, varying the anchor texts in the inbound links will steer you clear of any potential link spamming penalty.

Also note the linking page titles, as you can see they are a very close matched to automotive related key phrases. This is one of the reasons thepartsbin.com site is at top of the search results for car parts related terms.

The results of checking inbound links to the Thepartsbin.com site in Links Plus.

In conclusion

Link popularity is the driving force behind top engines rankings. Over the last few years Google has gotten especially good at separating the low quality links from the really valuable ones, and it's proven by the relevancy of their results and overall worldwide market share. The good news is we can all learn a lot about how our competitors get top ranking by studying carefully their inbound links and examine closely what those links say about their site, i.e. anchor text. It's your job as a webmaster to study, and test the affects of the off-page ranking factors. You can turn this knowledge to your advantage by building even stronger link popularity for your site.