Computing One-Sided Lower Prediction Limits

Note: See Calculating Various Statistical Intervals in the SAS/QC Sample Library.

You can specify options after the slash (/) in the INTERVALS statement to control the computation and printing of intervals. The following statements produce a table of one-sided lower prediction limits for the mean, which is displayed in Figure 5.26:

title 'Statistical Intervals for Fluid Weight';
proc capability data=Cans noprint;
   intervals Weight / methods = 1 2
                      type    = lower;
run;

The METHODS= option specifies which intervals to compute, and the TYPE= option requests one-sided lower limits. All the options available in the INTERVALS statement are listed in Summary of Options and are described in Dictionary of Options.

Figure 5.26: One-Sided Lower Prediction Limits for the Mean

Statistical Intervals for Fluid Weight

The CAPABILITY Procedure
One-Sided Lower Statistical Intervals for Weight Assuming Normality

Approximate Prediction
Limit For All of k Future
Observations
Confidence k Lower Limit
99.00% 1 11.90
99.00% 2 11.89
99.00% 3 11.88
95.00% 1 11.93
95.00% 2 11.92
95.00% 3 11.91
90.00% 1 11.95
90.00% 2 11.93
90.00% 3 11.92

Prediction Limit For the
Mean of k Future Observations
Confidence k Lower Limit
99.00% 1 11.90
99.00% 2 11.93
99.00% 3 11.94
95.00% 1 11.93
95.00% 2 11.95
95.00% 3 11.96
90.00% 1 11.95
90.00% 2 11.97
90.00% 3 11.97