03-18-2014 11:09 AM
I have a data set containing 980 paired observations of fish length and age. I would like to use a bootstrapping approach to examine how sample size affects the precision of model parameter estimates.
I have used the following program to successfully create a dataset where 3 fish per cm length class are selected 1000 times from the original dataset:
PROC SURVEYSELECT DATA = AGE OUT = SAMPLE
METHOD = URS
N = 3
SEED = 9876
REP = 1000;
Next I fit model parameters to each replicate in this dataset:
PROC SORT DATA = SAMPLE;
PROC NLIN DATA = SAMPLE;
PARMS LINF = 550 K = .25 t0 = 0.1;
MODEL TL = LINF*(1-EXP(-K*(AGE-t0)));
OUTPUT OUT = FITTED;
I would like to create a dataset that contains parameter estimates for each replicate. The dataset would contain the following variables:
REPLICATE LINF K t0
and would look like this, for example:
1 568 .25 .02
2 520 .27 .14
3 491 .32 .01
I have also attached the SAS file.
Any help would be appreciated.
03-18-2014 12:22 PM
That was helpful in summarizing the parameter estimates by replicate. However, is there a way to get them into a format that is easier to work with? Ideally this would be a SAS data set.
03-18-2014 12:56 PM
In the example I gave, samplePE would be a SAS dataset containing the parameter estimates. That seemed to be what you wanted.