Mercurial > hg > camir-aes2014
annotate toolboxes/distance_learning/mlr/metricPsi/metricPsiPO.m @ 0:e9a9cd732c1e tip
first hg version after svn
| author | wolffd |
|---|---|
| date | Tue, 10 Feb 2015 15:05:51 +0000 |
| parents | |
| children |
| rev | line source |
|---|---|
| wolffd@0 | 1 function S = metricPsiPO(q, y, n, pos, neg) |
| wolffd@0 | 2 % |
| wolffd@0 | 3 % S = metricPsiPO(q, y, n, d, pos, neg) |
| wolffd@0 | 4 % |
| wolffd@0 | 5 % q = index of the query point |
| wolffd@0 | 6 % y = the ordering to compute |
| wolffd@0 | 7 % n = number of points in the data set |
| wolffd@0 | 8 % pos = indices of relevant results for q |
| wolffd@0 | 9 % neg = indices of irrelevant results for q |
| wolffd@0 | 10 % |
| wolffd@0 | 11 % S is the vector of weights for q |
| wolffd@0 | 12 |
| wolffd@0 | 13 yp = ismember(y, pos); |
| wolffd@0 | 14 NumPOS = sum(yp); |
| wolffd@0 | 15 PosAfter = NumPOS - cumsum(yp); |
| wolffd@0 | 16 |
| wolffd@0 | 17 yn = ~yp; |
| wolffd@0 | 18 NumNEG = sum(yn); |
| wolffd@0 | 19 NegBefore = cumsum(yn) - yn; |
| wolffd@0 | 20 |
| wolffd@0 | 21 S = zeros(n,1); |
| wolffd@0 | 22 |
| wolffd@0 | 23 S(y) = 2 * (yp .* NegBefore - yn .* PosAfter) / (NumNEG * NumPOS); |
| wolffd@0 | 24 |
| wolffd@0 | 25 end |