6. SIMPLE REGRESSION ANALYSIS › 6.3 Standard Output

6.3 Standard Output

Simple Regression Analysis produces plots that track both the
historical data and the least squares trend line over time.
Forecasted future values of the trend line are represented.
Using Simple Regression Analysis screens, you can control the
number of forecast intervals, the axis titles, and the plot
title.

Additionally, Q&R formatted CSV files can be optionally
produced for later use by the CA MICS Q&R product. The
optional CSV file creation is discussed in chapter 7.

Figure 6-1 is a sample simple regression forecast plot that
shows the historical data, trend, and forecast for the SIO
count on channel 1.  The data is taken from the 4381- 2 I/O
workload analysis case study, which was originally developed
in Section 3.3.3.1.  The contents of this graph are defined
using the Simple Regression Analysis screen (see Figure 6-3).

The following is a description of the title information:

o  A user-specified title.  In this example, EXTENDED
   EXAMPLE.

o  A second user-specified title.  In this example, CHANNEL 1
   SIO COUNT VS MONTH.

o  A title line generated by the program.  This line contains
   the SYSID and ZONE that you selected for inclusion in the
   analysis.

o  A blank line.

o  The next three lines of the title are generated by the SAS
   PROC PLOT for printer plots.  They are not included on
   color graphics plots.  These lines are:

   -  Designation of the historical observations

   -  Designation of the regression values that
      correspond to the historical observation

   -  Designation of the forecasted values

o  Y-axis title line.  The Y-axis of the plot shows the
   range of values associated with the historical
   observations and the predicted values.  You may
   specify the label for this axis.

o  X-axis title line.  The X-axis of the plot shows the
   range of dates that correspond to the historical data
   and the predicted values.  The program generates the
   label for this axis.

                                                          EXTENDED EXAMPLE
                                                    CHANNEL 1 SIO COUNT VS MONTH
                                                       SYSID: TSO1   ZONE: 1

                                    PLOT OF CHAN1CNT*DATE    LEGEND: A = 1 OBS, B = 2 OBS, ETC.
                                    PLOT OF PX*DATE          SYMBOL USED IS *
                                    PLOT OF EST*DATE         SYMBOL USED IS +

            15000000 +



                                                                             A     A
            14000000 +



                                                                                                                   +
          C 13000000 +                                                                                        +
          H                                                                                              +
          A                                                                                        +
          N                                                                                   +
                                                                                        +
          1 12000000 +                                                             *
                                                                             *
          S                                                             *
          I                A     A                           *    *
          O                                            *
            11000000 +                           A
          C                                 *    *
          O                            *    A                           A
          U                      *
          N           A    *
          T 10000000 +*                A               A
                                                             A



             9000000 +
                                                                  A



             8000000 +


                     -+----------+----------+----------+----------+----------+----------+----------+----------+----------+
                   30SEP97    30NOV97    31JAN98    31MAR98    31MAY98    31JUL98    30SEP98    30NOV98    31JAN99    31MAR99

                                                                 MONTH ENDING

 Figure 6-1.  Simple Regression Forecast Plot