Hi Ömer,

First, note that you may not have enough observations to get good imputations with that many variables. Amelia might have poor properties in that case. You can save a lot of hassle here by not interacting the polynomials of time with the cross-section (setting "intercs = FALSE"). 

I imagine you have 500 GB of hard disk space, not RAM, but either way, this is probably related to the maximum vector size that R can handle, which is currently 2^31-1. Obviously that is *very* large, but if you want to go beyond that you would have to use R 3.0.0 (still under development) which will allow for longer vectors on certain machines. For more information, see this help file in R:

?"Memory-limits"

If you are on Windows, you might be able to increase the amount of memory dedicated the R process. 

Hope that helps!

Cheers,

matt.

~~~~~~~~~~~

Matthew Blackwell

Assistant Professor of Political Science

University of Rochester

url: http://www.mattblackwell.org

On Thu, Feb 7, 2013 at 12:10 PM, OMER FARUK Orsun <oorsun@ku.edu.tr> wrote:

Hi Matt,

Many thanks for your response. The missingness in my data is severe, as a result, I might need to introduce all available data. Is there another way to avoid memory related errors given that I have a 500 GB RAM computer?

Best Regards,

Ömer

_________________________________

Ömer Faruk Örsün

PhD Candidate

Department of International Relations

Koç University

CAS 289

_________________________________

On Thu, Feb 7, 2013 at 4:54 PM, Matt Blackwell <m.blackwell@rochester.edu> wrote:

Hi  Ömer, 

It seems as though you are running into memory issues with R itself. Note that using "intercs = TRUE" and "polytime = 2" will add 3*K variables to the data, where K is the number of dyads in the data. Given your description of the data, that could be an extremely large data set. You might want to run Amelia on a smaller subset of the data to see how the imputations go and then tentatively test out smaller imputation models. 

Hope that helps!

Cheers,

matt.

~~~~~~~~~~~

Matthew Blackwell

Assistant Professor of Political Science

University of Rochester

url: http://www.mattblackwell.org

On Thu, Feb 7, 2013 at 7:24 AM, OMER FARUK Orsun <oorsun@ku.edu.tr> wrote:

Dear Lister,

I am using Amelia II (Version 1.6.4) with a 500 GB computer specification and my data consist of directed dyads and my imputation model has 94 variables and 493,853 observations. I use the following command:

  

library(Amelia)

library(foreign)

mydata <- read.dta("data.dta")

require(Amelia)

 set.seed(1234)

a.out <- amelia(mydata, m=10, p2s = 2, tolerance = 0.005, empri = .1*nrow(mydata), ts="year", cs="dyadid" , polytime=2, intercs = TRUE)

After 7 hours, I receive the following message:

amelia starting

beginning prep functions

Error in cbind(deparse.level, ...) :

  resulting vector exceeds vector length limit in 'AnswerType'

I've already searched the Amelia II archieves and R archives, I was not able to locate a solution. 

I would deeply appreciate any help!

Best Regards,

Ömer

_________________________________

Ömer Faruk Örsün

PhD Candidate

Department of International Relations

Koç University

CAS 289

_________________________________

--
Amelia mailing list served by HUIT
[Un]Subscribe/View Archive: http://lists.gking.harvard.edu/?info=amelia
More info about Amelia: http://gking.harvard.edu/amelia
Amelia mailing list
Amelia@lists.gking.harvard.edu

To unsubscribe from this list or get other information:

https://lists.gking.harvard.edu/mailman/listinfo/amelia