In today?s Internet, which has reached the milestone of 100 mil domain names (according to Netcraft in October), attracting attention in the crowd is clearly the goal of each webmaster. Expressions like the ?attention economy? or ?to catch the eyeballs? are very popular on the Net. A major part of demand on the net is served today by search engines, which use link analysis algorithms (Google?s Pagerank is the most important such algorithm). Each User query results in a search engine results page which lists candidate web pages, according to their link analysis ranking. Given the multiple web pages for the same topic, competition for certain products or solutions which is based on a set of well known keywords, can be extremely hard. The link analysis ranking is essentially scoring a page on the inbound links: link from other pages that point to that page (in a simplified explanation). This property is also known as link popularity. Analysis on the sort of incoming links that can be effective, is also popular:
- Inbound only links (links which are not reciprocal)
- Reciprocal links (links exchanged between two web pages)
- Indirect link (link which points to a page (or set of pages) which then point to the page of interest
- Triangular linking (a more complex scheme in which 3 pages A,B,C are involved and their links form a triangle. A links to C directly and indirectly via B. B according to this scheme, can be considered the trusted third party which confirms the validity of the direct incoming link).
But the situation is not that simple. According to the link-based ranking (like Pagerank), not all links are of equal value. A link?s value is proportional to the ranking of the linking (or pointing) page and (to complicate it further) inversely proportional to the number of outgoing links of that page (sometimes called outdegree). How is this inbound linking achieved? This is achieved in ways of variable acceptance:
- By offering something of value (e.g. an interesting article, a useful web service, a useful download) to which others choose to refer and provide a link
- By posting content on other pages (article banks, forums) which links back to the page of interest
- By having a site listed in a directory
- By reciprocal link exchange
Within this context, the so called ?link economy? has emerged. Trading (selling and buying) links is a practice that has emerged. New negotiation terms have emerged (e.g. PR 5/60 means selling a link from a pagerank 5 web page, which has 60 outbound links). The level of trust is also evaluated during trading (e.g. a DMOZ listed page is said to be highly trusted).Many offer links in return for content or forum participation. Reciprocal link exchange campaigns are also carried out.
Linking controversy The option to pay for links is introducing bias in the natural linking process. This has raised concerns on its effect on the user experience (e.g a web site under construction having an incoming link from a PR7 page with a low outdegree, is a PR6 though it has nothing to offer). The high number of new directories (given the low cost to develop one) has definitely started defeating their purpose. Some attempt to make a short term profit from this inbound link frenzy, exploiting the lack of knowledge on what may be valuable. A link from the majority of these new directories does not have any value. Building links that will produce long term value, must be the goal. In order to achieve this quality info and/or service content is required.
Copyright 2006 ? Kostis Panayotakis
