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Measure of Accuracy

Two measures are used here to score the methods. The accuracy which ranges from 1 (perfect prediction) to 0 (all wrong)
\begin{displaymath}
Q_2=\frac{(number \quad of \quad correct \quad predictions)}{whole \quad set} \; .
\end{displaymath} (1)

and the correlation coefficient
\begin{displaymath}
C= \frac{(tp*tn-fp*fn)}{\sqrt{(tp+fp)(tp+fn)(tn+fp)(tn+fn)}} \; .
\end{displaymath} (2)

where $tp$, $tn$, $fp$, and $fn$ are respectively the true positive, true negative false positive and false negative. $C$ ranges from 1 (perfect prediction) to -1 (inverse prediction) and is 0 for a random assignment.

2003-06-12