Calculates the difference between positive x and y values
RelativeDifference(X, Y, epsilon =10^-10,na.rm=FALSE)
Arguments
X: either a value or numerical vector of [1:n]
Y: either a value or numerical vector of [1:n]
epsilon: Optional, If both x and y are approximatly zero the output is also zero
na.rm: Optional, function does not work with non finite values. If these cases should be automatically removed, set parameter TRUE
Details
Contrary to other approaches in this cases the range of values lies between [-2,2]. The approach is only valid for positive values ofX and Y. The realtive difference R is defined with
R=0.5∗(X+Y)Y−X
Negative value indicate that X is higher than Y and positive values that X is lower than Y.
Returns
R
References
Ultsch, A.: Is Log Ratio a Good Value for Measuring Return in Stock Investments? GfKl 2008, pp, 505-511, 2008.
Author(s)
Michael Thrun
Note
It can be combined with the GabrielClassificationError if a clear baseline is defined.