Hey everyone at SAS, My question very simple OK. I have regression with just continuous variable, no CLASS variable. proc glm data=in; model y = x ; run; quit; At specific values of x, I can predict y and have confidence interval for prediction. x1=12 and x2=10 I know the predicted value and the confidence interval around each prediction. But my question how I find confidence interval for the prediction at x1 minus the prediction at x2? This is what I want to do; find the confidence interval around the difference in predicted values? I have tried using estimate and contrast but not working for a difference in predicted value. Really appreciate help! ... View more

Hello SAS Community, I use band to annotate graph with gray box. But I need box to finish at x=0, and it keep going. How I stop the grey box at 0, just get the yellow area (below)? I use code:  data boundary; do x = -0.002 to 0 by .00001; up1=0; output; end; run; data plot; set plot_data boundary; run; proc sgplot data=plot; band x=x upper=0 lower=-0.002 / fillattrs=(transparency=0.5 color=gray); yaxis max = 0.005 grid; xaxis max = 0.005 grid; run; Thank you for help! ... View more

Hello to Sas community, I would like help to get into table - like outest table - the confidence interval and standard error for the variables from proc nlin. How do you do? I have statement like this so I am get parameter for every by variable patient. I will get the estimate for a,...,f out in parameters_out but the confidence limits I do not get. I see PROC REG has some TABLEOUT - is similar in PROC NLIN? I cannot find. Help would be really good thank you! proc nlin data = datafull_2016_2022 plots = fit maxiter = 200 save outest = parameters_final; by prtcpt; parameters a=-10 / pdata=parameters_init; model y = a*exp(x/b) + c*exp(x/d) + e*x + f; run; ... View more

Hi SAS community   I have data over time for ~200 participants. For each participant, I want to fit the same model, but I have a different set of initial conditions for the PROC NLIN routine (derived by looking at data for each paritcipant). How do I get this to work (code below)? Any help really appreciate. I keep get error like this: NOTE: DER.a not initialized or missing. It will be computed automatically. NOTE: DER.b not initialized or missing. It will be computed automatically. NOTE: DER.c not initialized or missing. It will be computed automatically. NOTE: DER.d not initialized or missing. It will be computed automatically. WARNING: Zero observations could be evaluated. NOTE: The data set WORK.PARAMS_OUT_4 has 0 observations and 9 variables.   data initial_params; set in.initial_params; nf+1; call symputx("last_nf",nf); run; data participant_data; set in.participant_data; run; %macro fit; %do j=1 %to &last_nf.; data _null_; set initial_params; where nf=&j; call symputx("beta10",beta10); call symputx("beta20",beta20); call symputx("beta30",beta30); call symputx("beta40".beta40); call symputx("participant",subject); run; proc nlin data = participant_data g4 plots = fit maxiter = 50 outest = params_out_&j.; where subject="&participant"; parameters a = &beta10. &beta20. = -3 c = &beta30. d = &beta40.; model response = a*exp(time/b) + c*time + d; run; %end; %mend; %fit; suggesting what I do wrong would be very helpful to me! ... View more