R/tam_difference_quotient.R

In alexanderrobitzsch/TAM: Test Analysis Modules

## File Name: tam_difference_quotient.R
## File Version: 0.07

tam_difference_quotient <- function( d0, d0p, d0m, h)
{
    d1 <- ( d0p - d0 ) / h
    d2 <- ( ( d0p - d0 ) - ( d0 - d0m ) ) / h^2
    res <- list( d1=d1, d2=d2 )
    return(res)
}

tam_mml_3pl_difference_quotient <- tam_difference_quotient