Previous Topic: 10.3.2.1 Model Analysis ReportNext Topic: 10.3.2.3 R-Square Ranking


10.3.2.2 Residual Analysis Report


The Residual Analysis Report details how the business element
based model you propose fits the historical data series.  A
Residual Analysis Report for the BILEXCPS data element is
shown in Figure 10-2.   The following information is shown:

BUSINESS
ELEMENT      The data element that is named as the dependent
BASED        element on the Business Element Forecasting
FORECAST OF: control screen (Figure 10-3).

MODEL BASED  The business elements that are used to develop
ON BUSINESS  the model.  This list may differ from the list
ELEMENTS:    of business elements specified in the Model
             Analysis Report.  This difference results from
             the deletion of proposed business elements based
             on the minimum r-squared improvement criterion.

The columns of the report are discussed below:

DATE:        The date ending value for the week or month
             represented by the observation.

Resource     The actual historical observations for the
Usage        data element (in this case, BILEXCPS) being
Element      modeled.  Note that if the last two characters
(BILEXCPS):  of the data element name are TM, the program
             assumes that the value is in seconds and uses a
             SAS TIME10.1 format for the report.

Two columns appear under the heading BUSINESS ELEMENTS for
each independent element used in the model.

NAME:        The name of the business element.

VALUE:       The user-supplied business element value.

The remaining columns of the report are as follows:

PREDICTED    The y value predicted for the interval using the
(BILEXCPS):  regression equation fit to the historical data.
             Note that if the last two characters of the data
             element name are TM, the program assumes that
             the value is in seconds and uses a SAS TIME10.1
             format for the report.

RESIDUAL     The error term, e, in the regression equation.
(BILEXCPS):  The residual is equal to the difference between
             the actual historical observation and the
             predicted value.  The residual value for a point
             deleted from the modeling process is of no
             concern since the model was not developed to
             account for the observation.  A SAS TIME10.1
             format is used if the variable name ends in
             TM.

PLOT OF       The residual values plotted over the range from
RESIDUALS:    minus to plus the maximum residual value.

CONFIDENCE   The confidence limits for the forecast.  The
LIMITS:      confidence limits bound the potential error (e)
             that may exist in the forecasts produced by the
             model.

CA MICS Capacity Planner BUSINESS ELEMENT FORECAST AND RESIDUAL ANALYSIS BUSINESS ELEMENT BASED FORECAST OF: BILEXCPS MODEL BASED ON BUSINESS ELEMENTS : INVOICES UPDATES OPN_ITEM -BUSINESS-ELEMENTS- PREDICTED RESIDUAL -------------PLOT OF RESIDUALS------------- CONFIDENCE DATE BILEXCPS NAME VALUE BILEXCPS BILEXCPS -58 0.0 +58 LIMITS +/- ------- ---------- -------- --------- ---------- ---------- ------------------------------------------- ---------- 31JAN98 4205.00 INVOICES 24017 4147.62 57.38 | 0+++++++++++++++++++ | 172.66 UPDATES 3145 | 0 | OPN_ITEM 47752 | 0 | | 0 | 28FEB98 4268.00 INVOICES 21570 4292.32 -24.32 | --------0 | 145.01 UPDATES 2960 | 0 | OPN_ITEM 51552 | 0 | | 0 | 31MAR98 3970.00 INVOICES 23411 3932.92 37.08 | 0++++++++++++ | 133.57 UPDATES 2012 | 0 | OPN_ITEM 49896 | 0 | | 0 | 30APR98 4384.00 INVOICES 21644 4391.34 -7.34 | --0 | 171.87 UPDATES 2500 | 0 | OPN_ITEM 45144 | 0 | | 0 | 31MAY98 3908.00 INVOICES 23476 3961.48 -53.48 | ------------------0 | 115.22 UPDATES 2709 | 0 | OPN_ITEM 53136 | 0 | | 0 | 30JUN98 3595.00 INVOICES 26311 3644.67 -49.67 | -----------------0 | 171.37 UPDATES 2108 | 0 | OPN_ITEM 48384 | 0 | | 0 | 31JUL98 3651.00 INVOICES 24774 3610.66 40.34 | 0+++++++++++++ | 157.48 UPDATES 2103 | 0 | OPN_ITEM 55512 | 0 | | 0 | 31AUG98 . INVOICES 25000 3764.39 . | 0 | 133.61 UPDATES 2000 | 0 | OPN_ITEM 49000 | 0 | | 0 | 30SEP98 . INVOICES 27000 3483.33 . | 0 | 224.90 UPDATES 2600 | 0 | OPN_ITEM 54000 | 0 | | 0 | 31OCT98 . INVOICES 23000 3893.67 . | 0 | 292.69 UPDATES 3150 | 0 | OPN_ITEM 60000 | 0 |


 Figure 10-2.    Extended Example Residual Analysis Report