One of the most powerful formulations uses binary variables to represent the presence of a rotamer and edges in the final solution, and constraints the solution to have exactly one rotamer for each residue and one pairwise interaction for each pair of residues:
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Now, we must make the central assumption of the piling-up lemma : the binary variables we are dealing with are "'independent "'; that is, the state of one has no effect on the state of any of the others.
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When used in the constraints themselves, one of the many uses of Big M, for example, refers to ensuring equality of variables only when a certain binary variable takes on one value, but to leave the variables " open " if the binary variable takes on its opposite value.
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When used in the constraints themselves, one of the many uses of Big M, for example, refers to ensuring equality of variables only when a certain binary variable takes on one value, but to leave the variables " open " if the binary variable takes on its opposite value.
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Consider a standard table showing the association between two binary variables with frequencies a = true positives = 49005929, b = false positives = 50994071, c = false negatives = 50994071 and d = true negatives = 849005929 . In this case the odds ratio ( OR ) is equal to 16 and the relative risk ( RR ) is equal to 8, 65.
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This equation clearly has the same "'form "'as the ( blue ) equation expressing the mutual information between the feature set and the category variable; the difference is that the sum \ textstyle \ sum _ { f _ i \ in F } in the " category utility " equation runs over independent binary variables F = \ { f _ i \ }, \ i = 1 \ ldots n, whereas the sum \ textstyle \ sum _ { v _ i \ in F _ a } in the mutual information runs over " values " of the single m ^ n-ary variable F _ a.