0. Initializing:
- Random selection of one motif occurrence for every sequence.
- Align the motifs to compute for the first time the content of the
matrices M and B.
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1. E step:
- In the first sequence, use the matrices M i B
to score every candidate segment of 10 bps
- For every segment, normalize the score according to the rest of candidates (computing a weight):
- Repeat the same operation for the rest of sequences, recording both
the candidates segments and their scores (weights), taking into account
the current estimation of the motif and background (matrices M
and B).
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2. M step:
- Update the matrices M and B with every candidate:
- M:
For each nucleotide in a candidate, according to the position within the motif,
update the corresponding position by adding the weight.
- B:
For each nucleotide of a sequence that is not within the corresponding motif,
update the background matrix by adding the weight.
- Normalize the matrices.
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3. Repeat steps 1 and 2 to convergence
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