I am in need to calculate the initial and final NLLS of ai, bi, ci. With this I have the initial estimates of ai, bi, ci. I aware that the following equations would help to calculate the initial and final NLLS . However, I am struggling to write the SAS code through PROC NLIN. I would be much thankful, if anyone may help to write the SAS Code PROC NLIN.
The PROC NLILN documentation contains a Getting Started example as well as more compilcated examples. To use the procedure your data set should contain MULTIPLE pairs of the (x, y) data values. A typical usage is as follows:
proc nlin data=Have;
parms a=37 b=3900 c=0.3;
model y = a*exp(-b*(x-c)**2);
run;
However, I will point out that you can solve this problem by using PROC GENMOD (or even PROC REG). If you take the log of both sides, your model becomes
log(Y) = log(a) - b*(x-c)**2
which (if you reparametrize) is equivalent to a quadratic model for log(Y):
ANOVA, or Analysis Of Variance, is used to compare the averages or means of two or more populations to better understand how they differ. Watch this tutorial for more.