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Neural Gas with Competitive Hebbian Learning

5.4.5

lambda_i
lambda initial ($\lambda_i$).
lambda_f
lambda final ($\lambda_f$).
epsilon_i
epsilon initial ($\epsilon_i$).
epsilon_f
epsilon final ($\epsilon_f$).
t_max
The simulation ends, if the number of input signals exceed this value (tmax).
edge_i
Initial value for time-dependend edge aging (Ti).
edge_f
Final value for time-dependend edge aging (Tf).
Edges are removed with an age larger than the maximal age T(t) whereby

\begin{displaymath}
T(t) = T_i(T_f/T_i) ^ {t/t_{\rm max}}.\end{displaymath}

The reference vectors are adjusted according to

\begin{displaymath}
\Delta \mbox{\bf w}_i = \epsilon(t) \cdot h_\lambda(k_i(\mbo...
 ...$\xi$},{\cal A})) \cdot (\mbox{\boldmath$\xi$}- \mbox{\bf w}_i)\end{displaymath}

with the following time-dependencies:

\begin{displaymath}
\lambda(t) = \lambda_i (\lambda_f/\lambda_i)^{t/t_{\rm max}}\end{displaymath}

\begin{displaymath}
\qquad\epsilon(t) = \epsilon_i(\epsilon_f/\epsilon_i)^{t/t_{\rm max}}\end{displaymath}

\begin{displaymath}
h_\lambda(k) = \exp(-k/\lambda(t)).\end{displaymath}



Hartmut S. Loos
10/19/1998