I am just trying to redefine "The Boston Matrix" in terms of keypharse analysis, hoping that it will help in your investments.

There are three steps to it,

1. Market

2. Competition

3. Conversion Ratio

Let me explain it one by one:-

Market:

Check different key phrases using suggestion tools like word tracker,inventory.overture.com/d/searchinventory/suggestion/ or www.espotting.com/popups/keywordgenbox.asp , it doesn't have to be perfect as we are just looking for keyphrases with high search shares.Choose as many as possible with promising market.Google's Adword can also be used.

Competition:

Search in Google or yahoo and see how many sites are listed under respective key phrase search.For example when I search for 'key phrase' in google it says, - Results 1 - 10 of about 4,800,000 for 'key phrase'- this gives primary idea of competition. Take first ten websites in SERP and check following factors:-

1. Back Links (directly proportional to PR)

2. Saturation

3. Ranked Page's onpage attributes like Title, keyword density e.t.c

Competition is directly proportional to Back Links, Saturation and onpage factors but I consider back links more crucial as achieving better saturation level along with onpage optimization is comparatively easier to obtain.

Conversion Ratio:

If 100 visits are made to your website from a key phrase, how many will get converted (sigup or buy).For example key phrase 'mortgage quote' will have higher conversion ratio compared to 'mortgage rate' as person searching for 'mortgage quote' is more likely to signup.

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