31 lines
No EOL
922 B
Matlab
31 lines
No EOL
922 B
Matlab
% implements Classify, return the predicted class for each row (we'll call each row x) in data
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% by computing the posterior probability that x is in class 1 vs. class 2 then
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% these posterior probabilities are compared using the log odds.
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function [predictions] = Classify(data, m1, m2, S1, S2, pc1, pc2)
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% calculate P(x|C) * P(C) for both classes
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pxC1 = mvnpdf(data, m1, S1);
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pxC2 = mvnpdf(data, m2, S2);
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g1 = log(pxC1 * pc1);
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g2 = log(pxC2 * pc2);
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% TODO: calculate log odds, if > 0 then data(i) belongs to class c1, else, c2
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log_odds = g1 - g2;
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% for i = 1:length(data)
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% if g1 > g2
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% predictions(i) = 1;
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% else
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% predictions(i) = 2;
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% end
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% end
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% TODO: get predictions from log odds calculation
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[num_rows, ~] = size(data);
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predictions = zeros(num_rows,1);
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for i = 1:num_rows
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predictions(i) = log_odds(i) > 0;
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end
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end % Function end |