Plot peeling trajectory for current rule:

traj ()

Arguments: none.

Remarks:

   This command plots the peeling trajectory for the current rule as
   described in Friedman and Fisher (1997), Sections 9 and 13. Each point
   represents the output mean and support for a potential box.
   Individual boxes can be (repeatedly) selected by moving the cross-hair
   with the mouse to that point and clicking the left mouse button. A number
   then appears on the plot near the selected point, identifying it. These
   numbers can then be entered (one at a time) at the prompt

      Different box {>traj()}. Box number = (<cr>=no)

   in the SuperGEM dialog window. This provides a summary of the indicated
   box. The first (unsolicited) summary is for the (upper) leftmost point,
   representing the (smallest) box with the highest output mean.

   The format of the box summary in the SuperGEM dialog window is as follows.
   The first line shows the rule number in the covering sequence, the selected
   box number, and the number of deleted "redundant" variables (see below).
   The next two lines provide a table of statistics based on the
   training and test data respectively (rows). The first column is the output
   mean over the entire data set used to construct the rule. This is either the
   "global" mean (first rule) or that of the data "remaining", after data
   covered by previous rules have been removed. The second column is the output
   mean in the selected box, and the third column its support.

   Following the statistical summary is the definition of the box. This is
   presented in the form of a table. Each input variable defining the box is
   represented by one or more rows. Real valued inputs are represented by at
   least one and at most three rows, one row for each possible limit
   (lower, upper, not equal missing) on that variable. The first column 
   identifies the variable. The second column is a relational operator
   (>, <, !=) indicating the nature of the bound on that variable (lower,
   upper, not equal missing). The third column is the boundary value, and the
   fourth (in parentheses) is its quantile value (in percent) on the data
   set used to construct the rule (global or remaining).

   Each categorical variable defining the box is represented by at least two
   rows. The first row identifies the variable (first column), indicates that
   it is categorical ("cat - second column), and gives the fraction (percent)
   of observations in the total sample (global or remaining) that assume the
   categorical values that are in the box. Following this first row are one
   or more rows listing the values of the categorical variable that are in
   the box, four values per line.

   The input variables are listed in this table in order of their estimated
   importance to the box definition; more important variables appear higher in
   the table [see Friedman and Fisher (1997), Section 10]. The last two
   columns of the table have one entry for each variable. They show
   respectively the box mean and support resulting from removing that
   variable, and all those below it (less important), in the table.

   One can go back and forth between the two windows, repeatedly clicking
   additional points on the peeling trajectory and entering their numbers
   in the SuperGEM window. When the most appropriate box has been determined,
   its number is entered at the SuperGEM prompt, and then a null line (<cr>)
   is entered at the next prompt. This then becomes the chosen box for further
   analysis and interpretation. In order to reactivate the S command window,
   click the middle (unix) or right (wintel) mouse button on the peeling
   trajectory plot.

   After the appropriate box has been chosen, "redundant" variables can be
   removed from its definition as described in Friedman and Fisher (1997),
   Section 10. A table listing each of the variables (rows), in order of
   their estimated importance to the box definition, is displayed in the
   SuperGEM dialog window. The second column gives the name/number of the 
   respective variables. The two right most columns show respectively the
   box mean and support resulting from removing that variable and all those
   below it in the list. The numbers in the first column indicate the
   corresponding number of variables that will be deleted by selecting each
   respective row. The bottom row (0) gives the mean and support of the
   current box with no variables deleted.

   Following the table is the prompt

      Redundant variable elimination: delete how many? (<cr> = 0)

   Respond with the desired number (first column). The corresponding input
   variable (row), and all those below it, are thereby deleted from the box
   definition producing a new (larger/simpler) box for further analysis and
   interpretation. If no variables are to be deleted, simply enter 0 or <cr>.

   This approach allows input variables to be deleted only in nested subsets.
   If desired, additional individual inputs can be deleted (in any order) at
   a later stage in the analysis dialog (see "sens").