AMstart - Amelia

28 Feb 2004

Dear Prof. Scheve,

Thanks a lot for replying to my message. 

I got rid of those variables for which there was perfect linear dependence (there were 2
of them), and run Amelia but it did not work, the same message kept coming up:

Iteration Number:
sweep: elements of m cannot be zero
Currently active call: SWEEP [79]

When I tried to change the default start values it gives me either the option of a default
with covariances zero, or file with starting values (I wanted to write 2 as you suggested
me), however it asks me to enter the name of a file which contains the starting values and
hit return, am I supposed to create such a file? is it a matrix?

WHat I did was:
I set AMpri equal to 2 as it is advised for high missingness data
I described my fully variables
I left AMmtho under the default (should I change it to 2?)
I did not define any idvar (I have tried with and without and it does not make any
difference)
I did not define any time of sectional variable in the AMts and AMcs (or the AMusets,
AMusecs and AMtstep)
I did not ask for any nominal variable to be returned as such
I asked for 1 ordinal variable to be returned as such

I got the same message again...

Sorry for taking so much time out of you and again, thank you for helping me put here,

Yours

Jose Merino

----- Original Message -----
From: Kenneth Scheve &lt;kenneth.scheve(a)yale.edu&gt;
Date: Saturday, February 28, 2004 4:03 pm
Subject: Re: [amelia] run but

...

 Actually this message is not about which variables are fully 
 observed. It 
 usually indicates there is something wrong with the data or at 
 least that 
 portion of the dataset being used in the initial calculations.

 Did you try setting the AMstart global to "2" rather than the default?

 Also check and make sure that you have not included data for which 
 there is 
 perfect linear dependence between some group of variables.

 Ken

 At 03:53 PM 2/28/2004, Jose Antonio Pena Merino wrote:
 OK, the program is running now, I think I was
asking way too much   by 
 including too many variables and asking it to keep
all the   ordinal and 
 nominal as such.

However, even if it is running it keeps returning the following   message:>
 Iteration Number:
sweep: elements of m cannot be zero
Currently active call: SWEEP [79]

I define those variables which contain full information already,   but it 
 looks like Amelia keeps detecting one variable
with full   information. In 
 order to detect which one was it I kept adding
each variable to   the list 
 of fullys, but all of them were detected as
non-fully. So I   really do not 
 know why I keep getting the same message. In sum,
there is no   other 
 variable besides those already defined as fully
for which m=0   (that is, 
 with no missing values)

Thanks for clarifying this for me

Yours

Jose Merino  