One way that you can measure your websites’ SEO health is by figuring out if your most important web pages (such as those that contain your biggest selling services or products) have been placed in Google’s supplemental index.
Many people think that when Google ceased to label the supplemental results pages, that signaled the end of their supplemental index. False. Google made in clear in their article “Supplemental goes mainstream“, published at their Webmaster Central Blog, that:
“The distinction between the main and the supplemental index is therefore continuing to narrow. Given all the progress that we’ve been able to make so far, and thinking ahead to future improvements, we’ve decided to stop labeling these URLs as Supplemental Results. Of course, you will continue to benefit from Google’s supplemental index being deeper and fresher.”
The pages which are the first results for any SERPs are those in the main index. The only time you’ll find pages from the Google supplemental index is if there are very few or zero results for your chosen search term in the main index.
Furthermore, Google has a tendency to transfer old cached pages over to their supplemental index. These might be pages which aren’t even on your server any longer.
Bot Herding for PageRank Flow
For appearance in Google’s main index, your web pages must have a certain indefinite amount of Pagerank or “juice”, in addition to and apart from other relevant factors. Google makes use of PageRank values for setting crawling priorities and determining whether or not a document belongs in their main or their supplemental index.
Matt Cutts, who heads up the Google Webspam Team, has this to say:
“PageRank is the primary factor determining whether a URL is in the main web index vs. the supplemental results.”
Once you understand the common causes behind supplemental pages you will be able to determine which pages might be placed in the supplemental index. Then you’ll be able to improve your websites’ internal linking via links from fully indexed and more prominent pages added to your pages and your home site.
Effective Link Building
Andy Beal says something very similar to Matt Cutts:
“If you got 60,000 pages, and you only got ’this much’ PageRank, and you divide it [...he mumbles], some of them are going to be in the supplemental index. Given ‘this many people’ who link to you, we’re willing to include ‘this many’ pages in the main index.”
An SEO professional or a Link Builder will tend to advise you that the most highly effective way of getting your pages out of the supplemental results is by creating unique, high quality content and then doing promotional work to acquire inbound links.
That’s right, but why go through all that trouble without first seeing just how far you’re able to get with the PageRank that your site possesses now?
There is a handful of internal link-based strategies that you can use to fight supplemental results. One highly effective and widely used popular strategy has been dubbed “Bot Herding.”
This is merely a methodology for improving yourwebsite’s navigating system via control of the flow of PageRank for enhancing the prominence of your most valuable and important pages. You can achieve this through linking to them from pages within your domain, etc.
What commonly causes supplemental pages?
The main cause of Supplemental results is very simply a lack of Page Rank. Nevertheless, this is not the sole cause. There are several others:
- Pages with no or very low PageRank;
- Suspicious pages, including non-unique or irrelevant page content heading tags, meta tags, links to bad neighborhoods, and so on.
- Pages with canonicalization problems (duplicated content, too much content similarity);
- Lengthy URLs, especially ones with extensive parameters, starting with a question mark (?) and being separated with an ampersand (&) and are not rewritten;
- Pages with very little or zero original content;
- Poor website navigation;
- Keyword stuffing (using many irrelevant keywords);
- Orphaned web pages which no-one links to, including your own;
- Error pages, if a site does not use If-Modified-Since, Last Modified and/or Expires rules.
If you have pages that have been placed in the supplemental index, you know what to do. Remove them from there, save yourself money and time, and increase your website’s rankings!