There are many unique terms associated with search engine optimization and search engine marketing. Keyword Effectiveness Index – A WordTracker term that refers to the number of times a Keyword has appeared in WordTracker’s database compared with the number of competing Web pages.

DETAILED EXPLANATION

The KEI for a keyword should increase if its popularity increases. Popularity is defined as the "Count" or number of times it appears.

The KEI for a keyword should decrease if it becomes more competitive. Competitiveness is defined as the number of sites which a search engine e.g. Google displays when you search for that keyword using exact match search.

Exact match search means that a search engine searches for only those sites which use the keyword exactly as typed in by the user. It is the equivalent of entering:

 

Partial match search means that a search engine also searches for sites which contain the individual words of the keyword but not necessarily occurring together or in the order typed in by the user. It is the equivalent of entering:

 

Partial match search presents a distorted picture of the competitiveness of a keyword because when you optimize your site for a particular keyword, you are actually competing with sites which have used the keyword exactly as typed in by the user.

I have personally found Word Tracker a great resource for everyone who really understands the importance of market speak. It really can profoundly effect the outcome of any web enterprise. Today in the news I also found this article provides some insight. It might make the experienced SEO pro say no kidding. Though when discussing the topic of KEI, the object is to remove as much of the ambiguity as possible.