Answer / rishu

Suppose the Blast search returned 100 hits. Of these, 17
were false positives and we knew that there were 165
sequences in

the database which should have returned a hit with our
sequence.


To calculate the sensitivity and selectivity, we must
determine the number of true positives (ntp), the number of
false

positives (nfp) and the number of false negatives (nfn). We
are told that the number of false positives was 17, hence
the

number true positives must have been 100-17 = 83, as there
were 100 hits. Therefore we know that the search algorithm
found

83 of the 165 sequences it should have found, hence the
number of false negatives was 165-83 = 82. So, we know that
ntp = 83,

nfp = 17 and nfn=82. Using the equations in the notes, we
can calculate:

Sensitivity = ntp/(ntp+nfn) = 83/(83+82) = 83/165 = 0.50 (2
d.p)

Selectivity = ntp/(ntp+nfp) = 83/(83+17) = 83/100 = 0.83

Answer / sulochana

difference between bio and cheminformatics and their uses
in drug discovery

If the letters of the word ?rachit? are arranged in all possible ways and these words are written out as in a dictionary, what is the rank of the word ?rachit?. (a) 485 (b) 480 (c) 478 (d) 481

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Why use PatternHunter instead of Blast?

1 Answers  

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How did you get into the field of bioinformatics?

0 Answers  

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NLO : RPS : : ? : ZXA

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How can we find the direction of an nucleotide substitution, for example; C to T or T to C?

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What is PPAR gamma pathway?

1 Answers  

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The shape of a spot of light produced when bright sunshine passes perpendicular through a hole of very small size is (a) Square, because the hole is a square (b) Round, because it is an image of the sun (c) Round with a small penumbra around it (d) Square with a small penumbra.

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What is a DNA array?

0 Answers  

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If you had 1,500 base pair pieces of random DNA and you have to know how many of them had homology to known genes, what would you do to determine that?

1 Answers  

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what are databases used in bioinformatics?

1 Answers  

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How long will a train 100m long traveling at 72kmph take to overtake another train 200m long traveling at 54kmph?

2 Answers   Wipro,

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