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Old 09-06-2013, 10:35 PM   #1
pavan
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Location: Bangaluru

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Default E-value in Blast

Hello everybody!!

How blast results very with change in e-value.
If i change e-value from 10 to directly to some value like e10-6(0.000001)


Thanks
Pa1
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Old 09-08-2013, 04:56 AM   #2
GenoMax
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I am not sure if there is a question in your post or a statement but if that was a question then refer following:

http://blast.ncbi.nlm.nih.gov/Blast....YPE=FAQ#expect
http://www.ncbi.nlm.nih.gov/BLAST/tu...ltschul-1.html
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Old 09-08-2013, 08:59 AM   #3
Melissa
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You are asking how does reducing the E-value change your blast results if I understand correctly. When you change the E-value from 10 to 1E-6, you will remove results which are less significant and thus, you get lower number of results. The smaller the E-value, the more significant is the result. The smallest E-value you can get is 0.0. If two results contain E-value 0.0, I would look at the scores to find the most significant results.
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Old 09-09-2013, 09:09 PM   #4
A_Morozov
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Yeah, one more thing to keep in mind. E-value setting does not affect parameters of the alignment, it just makes BLAST display more or less hits.
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