Resources

Two-Parameter Weibull Q-Q Plot

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 /*          S A S   S A M P L E   L I B R A R Y                 */
 /*                                                              */
 /*    NAME: CAPWEIB1                                            */
 /*   TITLE: Two-Parameter Weibull Q-Q Plot                      */
 /* PRODUCT: QC                                                  */
 /*  SYSTEM: ALL                                                 */
 /*    KEYS: Capability Analysis, Quantile-Quantile Plots,       */
 /*   PROCS: CAPABILITY                                          */
 /*    DATA:                                                     */
 /*                                                              */
 /*    MISC:                                                     */
 /*                                                              */
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  options ps=60 ls=80;

  data failures;
     input time @@;
     cards;
  27.96  45.78  50.90  23.63  18.22
  44.91   9.44  45.20  43.80  46.81
  33.66  18.07  16.08  29.40  32.40
  52.92  29.35  18.05  16.75  21.37
  23.83  37.33  27.36  48.92  39.56
  28.02  19.27   6.12  65.80  21.07
  39.77   1.01  50.95  71.46  27.67
  20.24  30.56  14.98  45.79   5.95
  46.85  48.30  36.74  16.06  25.49
  40.16  40.59  51.31  20.43  57.33
   2.75  53.67  33.60  36.64  24.55
  33.47  28.05  32.46  33.39  31.35
  49.39  51.84  28.93  38.73   7.59
  47.98  60.80  45.20  56.51  34.16
  40.67  29.86  40.31  38.46  38.98
  41.66  43.29  40.75  52.92  33.84
  37.92  34.51  50.72   6.54  45.33
  34.99  23.18  70.52  46.94  16.39
  20.42  38.53  43.28  25.85   4.65
  56.43  51.78  51.15  12.05  28.54
  ;

  symbol1 c=white v=star h=1.5;

  title 'Two-Parameter Weibull Q-Q Plot of Failure Times';

  proc capability data=failures noprint;
     var time;
     qqplot / weibull2
              square
              href   = -5 to 1
              lhref  = 33
              vref   = 1 to 4
              lvref  = 33
              cframe = gray
              haxis  = axis1
              vaxis  = axis2;

     axis1 label=('log-Weibull Quantile');
     axis2 label=('log of Failure Time ');

  run;

  goptions reset=all;