Wisdom gleaned from different webmaster forums about finding the right keywords for your website:
"KEI is a measure of search frequency combined with number of pages competing. Its not how many are in the fight that matters - its WHO is in the fight. KEI tells how many but not who.
I look at KEI but don't let it decide what terms I will target. If I allowed an unfavorable KEI to scare me off of keywords I would be acting like a whipped dog and never accomplish anything less than easy.
I routinely go after terms with unfavorable KEI with good results - either because I can defeat the competitors there or because the search volume is so high and so diverse that almost anyone in the competition will get long tail traffic.
If I am going to make a serious attack on a search term, I go to Google and visit the top ten sites. I look to see how well optimized they are, I look at how many links they have, and I look at the strength of their content relevant to that term.
You can run something like the keyword difficulty tool at seomoz.org. That returns a list of the top ten sites, how many links they have broken down by .edu .gov and total, and lots of other information.
This tells you what you need to do if you want to compete for that keyword and is much more meaningful than KEI.
I subscribe to wordtracker. I used it every day. I consult it before each blog post and do research there before I begin writing every article. My purpose is to compose my posts and articles so that they are presented to high and relevant traffic. I pay no attention to KEI... in fact, I rarely go beyond seeing the variants for a search term. Instead I go for highest relevant traffic that uses natural language search terms that will appear in my post/article. My approach might be different if I was not doing this for a site that is powerful within it's niche. If my site was not very powerful within the niche I would select keywords where I could win top positions."
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"IMHO "KEI" ("Keyword Effectiveness Index") is no magic formula; the idea of researching all keywords associated with your market and then targetting those with the highest # of searches Vs the lowest # of competitors is no different to what all good SEO professionals do. The difference (it seems to me) is that it "encourages" you to target those "easier" terms at the expense of others, whereas my experience has clearly shown me that the best road to success is to target as many associated KW's & terms as you can; variety will not only provide proliferation of serps, but will allow you far more ("instant") insight into changing search trends, make your traffic figures far more stable (less prone to fluctuation due to those changing search trends), and will make your site much more secure against competition in the future (loss of pole position for one primary term will not result in the loss of 90% of your traffic)!
My conclusions: In a boxing match - "KEI" might win the first few rounds but "longtail" would take the match!"
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