I think this might work, but how would I output the coefficients into a new data set? I would be looking at getting the coefficients from hundreds of these measures, then plot the mean and + - 1 standard deviation for them.
If you use the ODS TRACE statement, you can find out the name of the output object that contains the coefficient and the mean and the std. Then, once you have then output object name(s), you can create an output dataset that contains the data points. From there, it would be fairly easy to graph the points.
For example, if you modified the above PROC NLIN code to use ODS TRACE:
ODS TRACE ON/ LABEL;
ODS TRACE OFF;
Then you would see in your SAS log:
Label: Iterative Phase
Label Path: 'The Nlin Procedure'.'Iterative Phase'
NOTE: Convergence criterion met.
Label: Convergence Status
Label Path: 'The Nlin Procedure'.'Convergence Status'
and the output dataset WORK.PARMEST would contain:
Obs Parameter Estimate StdErr Alpha LowerCL UpperCL Skewness tValue Probt
1 a 30.1779 1.2717 0.05 26.6473 33.7086 0.0359 23.73 <.0001
2 b 0.3366 0.0301 0.05 0.2531 0.4201 0.0559 11.19 0.0004
ODS TRACE and ODS OUTPUT work with any SAS procedure that creates output objects, so if you find that PROC NLIN is not the procedure you need, then you only need to use ODS TRACE ON/OFF around your new procedure to find out the names of the output objects.
In addition, if you have SAS 9.2, you can try using the ODS GRAPHICS ON/OFF statements around your STAT procedure to see whether there are any automatic graphics associated with your procedure of choice.