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Table 1 Definition of terms used in describing the MEME algorithm

From: The value of position-specific priors in motif discovery using MEME

n

number of input sequences

L

length of input sequences

X = {X1, ..., X n }

the set of n input sequences

w

width of a MEME motif

m = L - w + 1

number of positions for a site

γ

probability of a site in any sequence

θ

PSPM model of motif;

P = {Pi,j}

position-specific prior (PSP)

w 0

width for which input PSP is defined

Z = {Zi,j}

missing information variables for i [1, n],j [-L, L]

Z (t)

expectation of Z at EM iteration t

= Pr(Zi,j= 1|ϕ(t))

prior probability given PSP & model

ϕ (t)

model parameters at EM iteration t

ϕ = {θ, γ, P}

all sequence model parameters