This function measures the Amari error between two matrices.
Usage
amari_distance(Q1, Q2)
Arguments
Q1
First matrix.
Q2
Second matrix.
Value
It returns the Amari error between two matrices $Q1$ and $Q2$.
Details
The Amari error $D(Q1|Q2)$ between two M x M matrices $Q1$ and $Q2$ is evaluated through
$$D(Q1|Q2)=\frac{1}{2M(M-1)}\sum_{j=1}^M\left(\frac{\sum_{i}|a_{ij}|}{max_{i}|a_{ij}|}-1\right)+\frac{1}{2M(M-1)}\sum_{i=1}^M\left(\frac{\sum_{j}|a_{ij}|}{max_{j}|a_{ij}|}-1\right),$$
where $Q2$ is invertible and $a_{ij}$ is the $ij$th element of $Q1Q2^{-1}$.
References
Amari, S., Cichocki, A., Yang, H. et al. (1996). A New Learning Algorithm for Blind Signal Separation. Advances in Neural Information Processing Systems, 8, 757--763
Bach, F., Jordan, M. (2003). Kernel Independent Component Analysis. Journal of Machine Learning Research, 3, 1--48