GBARLINE Procedure

Example 2: Calculating Weighted Statistics

Features:	BAR statement options: AXIS= SUMVAR= PLOT statement options: AXIS= FREQ= SUMVAR=
Other features:	AXIS statement
Data set:	SASHELP.FAILURE
Sample library member:	GBLWTSTA

This example uses the FREQ= option to calculate weighted statistics for the line plot. During the manufacture of a metal-oxide semiconductor (MOS) capacitor, various defects and their frequencies were recorded.

bar-line chart showing weighted statistics

Program

goptions reset=all border;

data myfail;
   set sashelp.failure;
   label Cause='Defect';
    select (Cause) ;
      when ("Contamination")  Cost=3.5;
      when ("Metallization")  Cost=10;
      when ("Oxide")          Cost=10.5;
      when ("Corrosion")      Cost=4.5;
      when ("Doping")         Cost=3.6;
      when ("Silicon")        Cost=5.4;
      otherwise               Cost=1.0;
    end;
run;

title1 "The Cost of Defects";

axis1 label=("Defect Count");
axis2 label=("Total Cost");

proc gbarline data=myfail;
   bar Cause / sumvar=Count axis=axis1;
   plot / sumvar=Count freq=cost axis=axis2;
run;
quit;

Program Description

Set the graphics environment.

goptions reset=all border;

This graph uses the data set entitled FAILURE found in the SASHELP library. Each observation of the FAILURE data set contains the type of manufacturing defect and a count of how many times it occurred. Define data that associates a cost with each defect. Assign a label of 'Defect' in place of the variable name in the data set.

data myfail;
   set sashelp.failure;
   label Cause='Defect';
    select (Cause) ;
      when ("Contamination")  Cost=3.5;
      when ("Metallization")  Cost=10;
      when ("Oxide")          Cost=10.5;
      when ("Corrosion")      Cost=4.5;
      when ("Doping")         Cost=3.6;
      when ("Silicon")        Cost=5.4;
      otherwise               Cost=1.0;
    end;
run;

Define the title.

title1 "The Cost of Defects";

Define the labels for the axes.

axis1 label=("Defect Count");
axis2 label=("Total Cost");

Produce the bar-line chart.The SUMVAR= option in the BAR statement specifies the variable that determines the height of the bars. The SUMVAR= option in the PLOT statement specifies the plot variable, in this case the Cause of Failure, or Defect.. GBARLINE multiplies the value of the FREQ= variable (cost assigned) by the value of the COUNT variable, and uses the result to determine the plot points.

proc gbarline data=myfail;
   bar Cause / sumvar=Count axis=axis1;
   plot / sumvar=Count freq=cost axis=axis2;
run;
quit;