missing value
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missing value



A question about missing values. 
I thought asreml would recognize the star (*) as a missing value,
However, in the following simple example, the program has taken it as a
valid zero-value
This in spite of the fact that one missing is given in the variable list.


------data--------

12 73
14 89
16 95
13 76
* 97

------as file------

test data to checking missing
  x
  y
test.dat
y ~ mu + x

----output---------
 ASREML [15 Feb 1999]  test data to checking missing 

 Wed May 12 10:14:14 1999 128.00 Mbyte    test
  Reading test.dat  FREE FORMAT skipping  0 lines
 Univariate analysis of y
 Using        5 records [of       5 read from       5 lines of test.dat
   ]
  Model term      Size Type    COL   Minimum    Mean      Maximum   #zero
#miss
   1 x               1 Covariat  1  12.00      13.75      16.00         0
  1
   2 y               1 Variate   2  73.00      86.00      97.00         0
  0
   3 mu              1 Constant Term
  Forming  3 equations:  3 dense
 Initial updates will be shrunk by factor    0.548
 LogL=-12.2458     S2=  139.17          3 df   1.0000
 Final parameter values                        1.0000

   Source               Model  terms     Gamma     Component    Compnt/StndErr
   Variance                 5      3   1.00000       139.167          1.22 P
                     Solution       Standard Error    T-value     T-prev
   1 x                        1        0.45        0.45 [DF F_inc F_all]
                    1  -0.625000       0.932626         -0.67
   3 mu                       1      265.72       64.82 [DF F_inc F_all]
                    2    92.8750        11.5359          8.05
 Finished: Wed May 12 10:14:14 1999   LogL Converged
 


2 more:

I was originally wondering whether records with missing covariates of 
fixed effect codes are discarded, I suppose they are.

How is the log likelihood calculated? Is it not
logl=-.5*N*log(2*pi)-.5*log(det(V))-.5*(e'*inv(V)*e)
but this gives me  logl =  -18.4339

julius
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Julius van der Werf				e-mail:jvanderw@metz.une.edu.au
Sr. Lecturer in Animal Genetics		www:   http://metz.une.edu.au/~jvanderw/
Division of Animal Science				phone: +61-2-6773-2092
School of Natural Resources and Rural Science		fax  : +61-2-6773-3275
University of New England				home : +61-2-6775-2442
Armidale, NSW 2350, AUSTRALIA	
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