Displaying 3 results from an estimated 3 matches for "petrova".
Did you mean:
petrov
2008 Apr 25
5
Non-linear system of equations
...I heard about nlsystemfit, but I don?t know how to run it exactly. I have tried the following code, but it doesn?t really work:
f1 <-y~ x[1]^2-x[2]^2-6
f2 <-z~ x[1]-x[2]-3
f <- list(f1=0,f2=0)
nlsystemfit("OLS",f,startvals=c(0,0))
Thank You in advance for your help.
Evgeniq Petrova
2010 Jun 25
1
Accessing matrix elements within a list
Hi there,
I cannot seem to figure out how to access the elements of a list if those elements are a matrix.
For example I have a the following list
df.list <- vector("list", 3)
and I have made each of the elements a matrix as follows
for(i in 1:3){
assign(paste("s",i, sep=""),matrix(0, nrow = 20, ncol = 5, byrow
= FALSE, dimnames = NULL))
}
# and then insert
2012 Jun 10
2
sampling weights for multilevel models
Dear all,
I am struggling with a problem which I have been reading on the forums about
and it did not seem to me that there is a precise answer to my question.
However, I still hope there is one.
I am working with http://timss.bc.edu/ PIRLS data and trying to conduct
multilevel analysis. There are different weights for each level of analysis
in the PIRLS dataset (e.g. there is a school