============================================================================= README file for the example files eight_jordan.xxx ============================================================================= Description: Jordan network (partially recurrent network) ============ for the task to learn the shape of a lying figure '8'. The task of this partially recurrent network is to predict the shape of a lying figure '8'. The problem is described in detail in J.L. Elman: Finding Structure in Time. Cognitive Science, 14:179-211, 1990 The two input units code the (x, y)-Position of the current point of the curve, the output units the (x', y')-Position of the next point. Usually 16 points (patterns) are used to approximate the shape of the figure 8, the central crossing point (0.5, 0.5) appearing twice, depending on which direction the stroke takes. The difficulty for the network arises from the input pattern of this central crossing point for which the network must predict two different successors (output patterns) depending on the previous point. See the user manual for a detailed description of Jordan networks and their usage. Network-Files: eight_jordan.net ============== This network file contains a trained jordan network for the task to predict the figure of a lying eight described above. The standard configuration file for this network is eight_jordan.cfg (one 2D display only). Pattern-Files: eight_016.pat ============== eight_160.pat The pattern files differ only in the number of patterns they contain, indicated in the name of the pattern file. The larger file consists of 10 concatenations of the smaller one Hints: ====== The easiest way to create Jordan or Elman networks is with the BIGNET panel from the info panel. All network parameters can then be specified in a special Jordan or Elman network creation panel called with the respective button in the BIGNET panel. If you want to train your own Elman or Jordan network from scratch, note to set the proper initialization function and initialization parameters. In this example, we use the following values: 1.0, -1.0, 0.3, 1.0, 0.5 (5 parameters). Remember to set the update function to JE_Order or JE_Special, depending on your task (see the SNNS user manual for more details). You may choose between four different learning functions. They are given here with some values for the learning parameters for which the training is relatively fast 1st 2nd 3rd 4th 5th JE_BP (Backprop) 0.2 JE_BP_Momentum 0.2 0.5 JE_Quickprop 0.3 2.0 0.0001 JE_Rprop 0.1 50.0 The behaviour of this network can very nicely be visualized with the network analyzer tool which can be called from the info panel with the GUI button as ANALYZER. The proceed as follows: Press ON and LINE (so that both buttons are highlighted) from the buttons at the right. Press SETUP and choose X-Y graph from the network analyzer setup panel. Choose the following values for axis, min, max, unit, grid: x 0.0, 1.0, 11, 10 y 0.0, 1.0, 12, 10 This specifies the display area to be [0, 1] x [0, 1] and the outputs of neurons 11 and 12 for x and y (the output units of the jordan network). Choose m-test: 16 in this network analyzer setup panel to test 16 patterns in a multiple inputs test sequence (You may also choose to test more or less input patterns. Finally, press the button M-TEST to test the trained network for the number of input patterns specified. ============================================================================= End of README file =============================================================================