Specifying a Known Proportion for np Charts
/****************************************************************/
/* S A S S A M P L E L I B R A R Y */
/* */
/* NAME: SHWNP3 */
/* TITLE: Specifying a Known Proportion for np Charts */
/* PRODUCT: QC */
/* SYSTEM: ALL */
/* KEYS: Shewhart Charts, np Charts, */
/* PROCS: SHEWHART */
/* DATA: */
/* */
/* REF: SAS/QC Software: Usage and Reference, Version 6, */
/* First Edition, Volume 1 and Volume 2 */
/* */
/****************************************************************/
data Circuits;
input Batch Fail @@;
datalines;
1 5 2 6 3 11 4 6 5 4
6 9 7 17 8 10 9 12 10 9
11 8 12 7 13 7 14 15 15 8
16 18 17 12 18 16 19 4 20 7
21 17 22 12 23 8 24 7 25 15
26 6 27 8 28 12 29 7 30 9
;
ods graphics on;
title1 'np Chart for Failing Circuits';
title2 'Using Data in CIRCUITS and Standard Value P0=0.02';
proc shewhart data=Circuits;
npchart Fail*Batch / subgroupn = 500
p0 = 0.02
npsymbol = np0
nolegend
needles
odstitle = title
odstitle2 = title2;
label Batch ='Batch Number'
Fail ='Fraction Failing';
run;
data Climits;
length _var_ _subgrp_ _type_ $8;
_p_ = 0.02;
_subgrp_ = 'Batch';
_var_ = 'Fail';
_type_ = 'STANDARD';
_limitn_ = 500;
proc shewhart data=Circuits limits=Climits;
npchart Fail*Batch / subgroupn = 500
npsymbol = np0
nolegend
needles;
label Batch ='Batch Number'
Fail ='Fraction Failing';
run;