Displaying 2 results from an estimated 2 matches for "kelcey".
2009 Oct 14
1
ltm package error for grm (IRT)
Using the grm function (graded response IRT model) in the ltm package I
receive the following error:
Error: subscript out of bounds
for several scales I'd like to examine. Here's a small example that if run a
few times will likley produce the error at least once
ch<-array(round(runif(50,1,5)),c(10,5))
grm(ch,start.val="random")
## or
2008 Aug 04
1
simulate data based on partial correlation matrix
Given four known and fixed vectors, x1,x2,x3,x4, I am trying to
generate a fifth vector,z, with specified known and fixed partial
correlations.
How can I do this?
In the past I have used the following (thanks to Greg Snow) to
generate a fifth vector based on zero order correlations---however I'd
like to modify it so that it can generate a fifth vector with specific
partial