|
|||||||||||||||||||
| 30 day Evaluation Version distributed via the Maven Jar Repository. Clover is not free. You have 30 days to evaluate it. Please visit http://www.thecortex.net/clover to obtain a licensed version of Clover | |||||||||||||||||||
| Source file | Conditionals | Statements | Methods | TOTAL | |||||||||||||||
| ROC.java | 68.8% | 69.2% | 66.7% | 68.9% |
|
||||||||||||||
| 1 |
package baseCode.math;
|
|
| 2 |
|
|
| 3 |
import java.util.Set;
|
|
| 4 |
|
|
| 5 |
import cern.jet.stat.Probability;
|
|
| 6 |
|
|
| 7 |
/**
|
|
| 8 |
* Functions for calculating Receiver operator characteristics.
|
|
| 9 |
* <p>
|
|
| 10 |
* Copyright (c) 2004 Columbia University
|
|
| 11 |
*
|
|
| 12 |
* @author Paul Pavlidis
|
|
| 13 |
* @version $Id: ROC.java,v 1.13 2004/08/16 00:21:40 pavlidis Exp $
|
|
| 14 |
*/
|
|
| 15 |
public class ROC { |
|
| 16 |
|
|
| 17 |
/**
|
|
| 18 |
* Calculate area under ROC. The input is the total number of items in the data, and the ranks of the positives in
|
|
| 19 |
* the current ranking. LOW ranks are considered better. (e.g., rank 0 is the 'best')
|
|
| 20 |
*
|
|
| 21 |
* @param totalSize int
|
|
| 22 |
* @param ranks Map
|
|
| 23 |
* @return AROC
|
|
| 24 |
*/
|
|
| 25 | 1 |
public static double aroc( int totalSize, Set ranks ) { |
| 26 | 1 |
return ROC.aroc( totalSize, ranks, -1 );
|
| 27 |
} |
|
| 28 |
|
|
| 29 |
/**
|
|
| 30 |
* Calculate area under ROC, up to a given number of False positives. The input is the total number of items in the
|
|
| 31 |
* data, and the ranks of the positives in the current ranking. LOW ranks are considered better. (e.g., rank 0 is the
|
|
| 32 |
* 'best')
|
|
| 33 |
*
|
|
| 34 |
* @param totalSize int
|
|
| 35 |
* @param ranks Map
|
|
| 36 |
* @param maxFP - the maximum number of false positives to see before stopping. Set to 50 to get the Gribskov roc50.
|
|
| 37 |
* If maxFP <= 0, it is ignored.
|
|
| 38 |
* @return AROC
|
|
| 39 |
*/
|
|
| 40 | 2 |
public static double aroc( int totalSize, Set ranks, int maxFP ) { |
| 41 | 2 |
int numPosSeen = 0;
|
| 42 | 2 |
int numNegSeen = 0;
|
| 43 | 2 |
int targetSize = ranks.size();
|
| 44 |
|
|
| 45 | 2 |
if ( targetSize == 0 ) {
|
| 46 | 0 |
return 0.0;
|
| 47 |
} |
|
| 48 |
|
|
| 49 | 2 |
if (totalSize <= 0) {
|
| 50 | 0 |
throw new IllegalArgumentException("Total size must be positive. ( received " + totalSize + ")"); |
| 51 |
} |
|
| 52 |
|
|
| 53 | 2 |
double result = 0.0;
|
| 54 | 2 |
for ( int i = 0; i < totalSize; i++ ) { |
| 55 | 13 |
if ( ranks.contains( new Integer( i ) ) ) { // if the ith item in the ranked list is a positive. |
| 56 | 4 |
numPosSeen++; |
| 57 |
// System.err.print(i + "+ " );
|
|
| 58 |
} else {
|
|
| 59 |
// System.err.print(i + "- " );
|
|
| 60 | 9 |
result += numPosSeen; |
| 61 | 9 |
numNegSeen++; |
| 62 | 9 |
if ( maxFP > 0 && numNegSeen >= maxFP ) {
|
| 63 | 1 |
break;
|
| 64 |
} |
|
| 65 |
} |
|
| 66 |
|
|
| 67 |
// if ( numPosSeen == targetSize ) { // we've seen all the positives, we can stop.
|
|
| 68 |
// result += numPosSeen * ( totalSize - i - 1 );
|
|
| 69 |
// break;
|
|
| 70 |
// }
|
|
| 71 |
} |
|
| 72 |
// System.err.println( numNegSeen + " negs, " + numPosSeen
|
|
| 73 |
// + " pos seen out of " + targetSize + " positives" );
|
|
| 74 |
|
|
| 75 | 0 |
if (numPosSeen == 0 ) return 0.0; |
| 76 |
|
|
| 77 | 2 |
if ( maxFP > 0 ) {
|
| 78 | 1 |
return result / ( targetSize * numNegSeen );
|
| 79 |
} |
|
| 80 | 1 |
return result / ( numPosSeen * ( totalSize - targetSize ) );
|
| 81 |
|
|
| 82 |
} |
|
| 83 |
|
|
| 84 |
/**
|
|
| 85 |
* For an AROC value, calculates a p value based on approximation for calculating the stanadard deviation. Highly
|
|
| 86 |
* approximate!
|
|
| 87 |
*
|
|
| 88 |
* @param numpos How many positives are in the data.
|
|
| 89 |
* @param aroc The AROC
|
|
| 90 |
* @return The p value.
|
|
| 91 |
*/
|
|
| 92 | 0 |
public static double rocpval( int numpos, double aroc ) { |
| 93 | 0 |
double stdev = Math.exp( -0.5 * ( Math.log( numpos ) + 1 ) );
|
| 94 | 0 |
double z = ( aroc - 0.5 ) / stdev;
|
| 95 |
|
|
| 96 |
/* We are only interested in the upper tails. */
|
|
| 97 | 0 |
if ( z < 0.0 ) {
|
| 98 | 0 |
z = 0.0; |
| 99 |
} |
|
| 100 | 0 |
return 1.0 - Probability.normal( z );
|
| 101 |
} |
|
| 102 |
|
|
| 103 |
} |
|
||||||||||