Relevance

• Google places more value on relevant backlinks because people are more likely to click on them. This is something they talk about in their “reasonable surfer” patent.
• What does this mean in real terms? If a plumber has backlinks from two pages, one about cats and one about installing boilers, chances are the latter is most valuable.
• This idea also plays out at the domain level.
• Readers of plumbing.com are more likely to click on a link to a plumber’s website than readers of cats.com.

Authority

• Backlinks from strong web pages usually transfer more “authority” than those from weak ones.
• Page-level authority is something we’ve studied a few times, and we’ve found a clear relationship between it and organic traffic.

Traffic

• Backlinks from high-traffic pages will usually send you more referral traffic than those from low-traffic pages. That’s obvious. The real question is whether backlinks from high-traffic pages positively affect rankings more than those from low-traffic pages?
• This is a question we recently tried to answer. We took the top-ranking pages for 44,589 non-branded keywords and looked at organic traffic to the pages that link to them.

Placement

• Because people are more likely to click prominently-placed links, some links on web pages likely pass more authority than others.
• If your link will likely end up in the site’s footer, or along with fifty other sites in the sidebar, then put your energy into other opportunities.

Followed vs. nofollowed

• Nofollowed backlinks don’t usually influence the linked page’s rankings—although they can.
• Because link building takes time and effort, it’s best to prioritize getting followed links. Just don’t kick up a fuss if you get a nofollowed link. It may still have some SEO value.

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