First the ART1 initialization function ` ART1_Weights` has to be
selected from the list of initialization functions.

` ART1_Weights` is responsible to set the initial values of the trainable
links in an ART1 network. These links are the ones
from F to F and the ones from F to F respectively.

The F F links are all set to 1.0 as described
in [CG87a]. The weights of the links from F to F are
a little more difficult to explain. To assure that in an initialized
network the F units will be used in their index order,
the weights from F to F must decrease with increasing index. Another
restriction is, that each link-weight has to be greater than **0** and
smaller than . Defining as a link-weight from a
F unit to the **j**th F unitthis yields

To get concrete values, we have to decrease the
fraction on the right side with increasing index **j** and assign this
value to . For this reason we introduce the value
and we obtain

is calculated out of a new parameter and the
number of F units **M**:

So we have two parameters for ` ART1_Weights`: and
. For both of them a value of 1.0 is useful for the
initialization. The first parameter of the initialization function is
, the second one is . Having chosen and
one must press the -button to perform
initialization.

The parameter is stored in the bias field of the unit structure to be accessible to the learning function when adjusting the weights.

One should always use ` ART1_Weights` to initialize
ART1 networks. When using another SNNS initialization function the
behavior of the simulator during learning is not predictable, because not only
the trainable links will be initialized, but also the fixed weights
of the network.

Niels.Mache@informatik.uni-stuttgart.de

Tue Nov 28 10:30:44 MET 1995