Question: I have been buying many links but it is hard to know which ones count and which ones do not. Is there any way to test if a link is clean and passes link authority?
Answer: If you are in a small market you can build links slowly and check your rankings as you build links, but there are two big problems with this:
- testing is slow, search algorithms frequently change, and ranking changes may occur outside of the effect of any individual link
- any market worth being in typically requires many links or at least a few high quality links that are hard to obtain
Here are a couple ways to test a link source to see if it passes trust.
Check the Pages it Links to
If all the pages that the page links to rank well for their target terms then that is a sign of trust, though it may help to analyze the link profile of those pages to see if those pages are also trusted from other links and anchor text.
If a page is a high authority page and has linked to other pages for over 6 months it should be passing PageRank. You can use the Wayback Machine to see what a page looked like in the past. If you see a PR8 page linking out to a dozen pages and one of the target pages has been linked to for 6 months, yet remains only a PR2, then odds are that page is not passing authority.
You can also look at advertiser turnover as a sign of not passing authority. You may also want to ask current advertisers if the page helped them at all. And, as a general rule of thumb, the more off topic the link ads are, the more that are sold on each page, and the more tightly they are grouped, the more likely it is that the page does not pass PageRank.
Bogus Anchor Text
You can add a word to your link anchor text and see if your target page ends up ranking for a phrase it already ranks for + that additional word.
For example, I could put info in a link pointing to www.SeoBook.com and see if this site starts ranking for things like seo book info or seo info. I could also point a bogus link at a mainstream media site using the same technique to see how the site's rankings react.
Link to an Orphan Page
Point your link at a page that is not indexed and see if search engines index that page. If that link passes trust you can 301 redirect the target page to the page you want to rank. If the link source hurts your rankings you can 301 redirect that link equity to a competitor's site (if you wanted to be dirty).
Speeding Up Your Tests
It helps to have a network of your own sites so you can point links at the link sources to help them get indexed quickly. Be aware though that if the link source's archived pages typically are not indexed in Google then it is not likely that the page will continue to pass link equity unless you help keep that page indexed by pointing a decent link or two at it.
Warnings
Each search engine evaluates links differently. Some sites that are banned in Google do well in Yahoo while other pages that are banned in Yahoo do well in Google.
Some links that may help in moderation may hurt your site if you are too aggressive with them (i.e. building too many links too quickly from low trust sources). Also, links that help a high authority site may not help a smaller and newer site as much as they helped the older and more trusted site. As a site ages its link profile can get a bit dirtier without as much potential risk.