I’m doing segmented regression.  I understand the theory behind it, but I can’t figure out which is the correct SAS model/output.  I found 2 different models in 2 books and they give slightly different results.  Any help is appreciated. Example data: Month    Mar    Apr    May    Jun    Jul (bp)    Aug    Sep    Oct    Nov rate       55     51     48      49      150           156    165     172   180 X           1      2       3        4         5              6       7         8       9 X2        -4      -3     -2       -1         0              1       2         3       4 X3        -4      -3     -2       -1         0              0       0         0       0 X4         0       0       0       0         0              1       2         3       4 Which of these three models is correct? Model 1: Proc reg; model rate = X   X4; run; (from Biostatistics for Animal Science) Model 2: Proc reg; model rate = X2  X4;run; Model 3: Proc reg; model rate = X3  X4;run; (from Draper and Smith, Applied reg analysis text book) Model 2 output is the exact same at model 1 except the intercept parameters are more meaningful. Model 3 is the same output as Model 2 except the slope after the break point (bp) is larger, and I don’t know why. ... View more

I've just began teaching myself plot procedures and very basic macros (ie %LET Statements).  I've written a program with the purpose of producing multiple plots in one PDF.  The program will be run annually.  Reading the support pages I've been able to get pieces of what I want, but I can't seem to get it all together.  So far the closest I've gotten is this: ods listing close; ods pdf file='O:\HIV Core Statistics Products\HIV Surveillance\Results\2014\plots\LHD_HTR.pdf'; proc gplot data = _LHD_HTR;     plot HTR*year=lhd;     symbol pointlabel=("#HTR") interpol=join value = dot;title 'LHD: HTR'; run;quit; ods pdf close; ods listing; It produces a PDF of my plot where I want it, but there are 2 issues:      1) I don't know how to make my next plot appear on the 2nd page of the PDF and not overwrite this one.      2) I'd like the "2014" in the 'ods pdf file= path' to be automatically updated each year.  I created a "%let this_yr = 2014" statement, but the file=path does not understand '&this_yr' or libnames. Thanks for any help. ... View more