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Package 'metagenomeSeq' - Bioconductor

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12 doZeroMStepDetailsValueMaximum-likelihood estimates are approximated using the EM algorithm where we treat mixturemembership $delta_ij$ = 1 if $y_ij$ is generated from the zero point mass as latent indicatorvariables. The density is defined as $f_zig(y_ij = pi_j(S_j) cdot f_0(y_ij) +(1-pi_j (S_j))cdotf_count(y_ij;mu_i,sigma_i^2)$. The log-likelihood in this extended model is $(1-delta_ij) logf_count(y;mu_i,sigma_i^2 )+delta_ij log pi_j(s_j)+(1-delta_ij)log (1-pi_j (sj))$. The responsibilitiesare defined as $z_ij = pr(delta_ij=1 | data)$.Updated matrix (m x n) of estimate responsibilities (probabilities that a count comes from a spikedistribution at 0).See AlsofitZigdoZeroMStepCompute the zero Maximization step.DescriptionUsagePerforms Maximization step calculation for the mixture components. Uses least squares to fit theparameters of the mean of the logistic distribution. $$ pi_j = sum_i^M frac1Mz_ij $$ Maximumlikelihoodestimates are approximated using the EM algorithm where we treat mixture membership$delta_ij$ = 1 if $y_ij$ is generated from the zero point mass as latent indicator variables. The densityis defined as $f_zig(y_ij = pi_j(S_j) cdot f_0(y_ij) +(1-pi_j (S_j))cdot f_count(y_ij;mu_i,sigma_i^2)$.The log-likelihood in this extended model is $(1-delta_ij) log f_count(y;mu_i,sigma_i^2 )+delta_ijlog pi_j(s_j)+(1-delta_ij)log (1-pi_j (sj))$. The responsibilities are defined as $z_ij = pr(delta_ij=1| data)$.doZeroMStep(z, zeroIndices, mmZero)ArgumentszzeroIndicesmmZeroMatrix (m x n) of estimate responsibilities (probabilities that a count comes froma spike distribution at 0).Index (matrix m x n) of counts that are zero/non-zero.The zero model, the model matrix to account for the change in the number ofOTUs observed as a linear effect of the depth of coverage.ValueList of the zero fit (zero mean model) coefficients, variance - scale parameter (scalar), and normalizedresiduals of length sum(zeroIndices).

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