Dear all

I am working in a research which need me to simulate data with LD item pairs (surface), I am not so familiar with r package, so I faced some problems when I used some codes by other researchers like Houts (2011). I make the holders of the LD pairs and complete the code, but I have all elements of matrices equal to zero, also no raw data files. It will be appreciated if you could help me or if you have a detailed explanation for the code you used to simulate raw data with LD.