Hello All,
I'm trying to print specific row and column for Observed_Scores matrix,
however, when I execute the command "Observed_Scores[1,1]", I get the
message "Error in Observed_Scores[1, 1] : incorrect number of
dimensions". Could you please help and let me know where is the mistake?
Here is my program:
library(ltm)
library(psych)
# Settting the working directory path to C:/NCME
path="C:/NCME"
setwd(path)
#IRT Data Simulation Routine#
n.exams = 500 #Sets number of examinees to be generated#
n.items = 20 #Sets number of items to be generated#
#The following intialize empty (NA) vectors or matrices#
beta.values = rep(NA,n.items)
resp.prob = matrix(rep(NA,n.exams*n.items),nrow=n.exams,ncol=n.items)
Observed_Scores = matrix(rep(NA,n.exams*n.items),nrow=n.exams,ncol=n.items)
#filling item parameters into beta.values
beta.values = runif(n.items,-2,2)
#Calculating Threshold
thresh.values = .5 * beta.values
#for (i in 1:10)
#{
#Using the function to generate the data
GenData <- congeneric.sim(N=500, loads = rep(.5,20), err=NULL, short = FALSE)
Observed_Scores = GenData[1]
Regards
Nidhi Kohli
Hello All,
I'm trying to print specific row and column for Observed_Scores matrix,
however, when I execute the command "Observed_Scores[1,1]", I get the
message "Error in Observed_Scores[1, 1] : incorrect number of
dimensions". Could you please help and let me know where is the mistake?
Here is my program:
library(ltm)
library(psych)
# Settting the working directory path to C:/NCME
path="C:/NCME"
setwd(path)
#IRT Data Simulation Routine#
n.exams = 500 #Sets number of examinees to be generated#
n.items = 20 #Sets number of items to be generated#
#The following intialize empty (NA) vectors or matrices#
beta.values = rep(NA,n.items)
resp.prob = matrix(rep(NA,n.exams*n.items),nrow=n.exams,ncol=n.items)
Observed_Scores = matrix(rep(NA,n.exams*n.items),nrow=n.exams,ncol=n.items)
#filling item parameters into beta.values
beta.values = runif(n.items,-2,2)
#Calculating Threshold
thresh.values = .5 * beta.values
#for (i in 1:10)
#{
#Using the function to generate the data
GenData <- congeneric.sim(N=500, loads = rep(.5,20), err=NULL, short = FALSE)
Observed_Scores = GenData[1]
Regards
Nidhi Kohli
Nidhi Kohli wrote:> Hello All, > > I'm trying to print specific row and column for Observed_Scores matrix, however, when I execute the command "Observed_Scores[1,1]", I get the message "Error in Observed_Scores[1, 1] : incorrect number of dimensions". Could you please help and let me know where is the mistake? Here is my program: > > > library(ltm) > library(psych) > > # Settting the working directory path to C:/NCME > > path="C:/NCME" > setwd(path) > > #IRT Data Simulation Routine# > > n.exams = 500 #Sets number of examinees to be generated# > n.items = 20 #Sets number of items to be generated# > > #The following intialize empty (NA) vectors or matrices# > beta.values = rep(NA,n.items) > resp.prob = matrix(rep(NA,n.exams*n.items),nrow=n.exams,ncol=n.items) > Observed_Scores = matrix(rep(NA,n.exams*n.items),nrow=n.exams,ncol=n.items) > > > #filling item parameters into beta.values > beta.values = runif(n.items,-2,2) > > #Calculating Threshold > thresh.values = .5 * beta.values > > > #for (i in 1:10) > #{ > > #Using the function to generate the data > GenData <- congeneric.sim(N=500, loads = rep(.5,20), err=NULL, short = FALSE) > Observed_Scores = GenData[1]Say str(Observed_Scores) and find that Observed_Scores is not a matrix but a list! If you want to extract the matrix (first element of GenData), then use Observed_Scores = GenData[[1]] Uwe Ligges> Regards > Nidhi Kohli > > ______________________________________________ > R-help at r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code.