The 94 keyword phrases suggested by Wordtracker when input to Adword Analyzer gave 84 keyword phrases with search returns, 10 with zero count over the month.In comparing the data on the same 94 keyword phrases input to Ad Words Analyzer & Wordtracker the number of reported user searches can be very different. There's on average 21 times more search reports through Ad Words Analyzer & Overture than through Wordtracker for the same keyword phrases. Of the 28 additional different keyword's found by Niche Finder, 11 produced search returns over the past month.
Conclusion As a keyword analyzer, Ad Words Analyzer ( & Niche Finder ) reported on average 21 times more searches for a two keyword phrase through Overture than did Wordtracker using its own database.This is mainly due to two factors: - The probable larger size of the Overture network and therefore ( 2.7 times ) bigger net with which to capture searches.
- It uses a broad match not an exact match for its search returns.
A more detailed review of this can be found at: A keyword analyzer - Which results can you believe, Wordtracker, Adword Analyzer or Niche Finder ?Some correction estimates applied for a single keyword search, also two & three keyword phrase searches, explain the differences in each case. The result for the single keyword variation agrees closely with the findings of another report entitled "Demystifying The Radically Different keyword Results Provided By Overture and Wordtracker" by Robin Nobles. Whilst keyword analysis of the number of searches showed these variations it's suggested Wordtracker returns are probably on the low side of what to expect.
Adword Analyzer ( or Niche Finder ) are on the high side for a precise phrase match. Whether you take Wordtracker returns and apply the estimated upward correction ( multiply by 2.7 ), or take the Adword Analyzer returns and apply the downward corrections ( divide the result by 4 to 12 depending on the number of words in the keyword phrase ) is a matter of choice. So, for a keyword analyzer - is one enough ? This is not as easy to answer as the case for a keyword generator, where using Adword Analyzer and Niche Finder as well as Wordtracker, more than doubled the number of relevant keyword phrases to choose from. As the competition for keyword's & phrases is always increasing, it's my opinion having more than one analyzer tool is always to your advantage. So is one keyword analyzer enough ?On the basis of these findings, I would have to say No ! Like all tools provided the limitations of each are understood no harm can come from using them. But don't think Keyword Analysis is an exact science ...... it's not ! | 
