|
Statistical modelling
This output differs from the one given earlier in that the error variance is
now shared between the random terms specified in the model. This ensures
that different fixed estimates are evaluated using standard errors that
have been calculated using the residual variations associated with the
appropriate layer(s).
Note that compared with the earlier analysis the
Wald statistics for ram breed and ewe breed have been reduced from 9.10
and 6.13, respectively, to the values 6.64 and 2.91; indeed the
effect of ewe breed is no longer significant.
|
|
**Estimated Variance Components **
| Random
term |
Component |
S.e. |
| RAM_ID |
0.067 |
0.089 |
| EWE_ID |
1.457 |
0.283 |
***
Residual variance model ***
|
Parameter
|
Estimate
|
S.e.
|
|
Sigma2
|
3.427
|
0.266
|
**Approximate stratum variances ***
| |
|
Effective
d.f.
|
| RAM_ID |
4.733
|
57.66
|
| EWE_ID |
6.490
|
297.74
|
| *units* |
3.427
|
332.60
|
* Matrix of
coefficients of components for each stratum
| RAM_ID |
10.31
|
0.42
|
1.00
|
| EWE_ID |
0.00
|
2.10
|
1.00
|
| *units* |
0.00
|
0.00
|
1.00
|
*** Deviance: -2*Log-Likelihood ***
| Deviance |
d.f. |
| 1817.10 |
685 |
***
Wald tests for fixed effects ***
| Fixed
term |
Wald
statistic |
d.f.
|
Wald/d.f.
|
Chi-sq
prob
|
| *
Sequentially adding terms to fixed model |
| YEAR |
230.32
|
5
|
46.06
|
<0.001
|
| SEX |
9.66
|
1
|
9.66
|
0.002
|
| AGEWEAN |
63.84
|
1
|
63.84
|
<0.001
|
| DL |
30.44
|
1
|
30.44
|
<0.001
|
| DQ |
78.41
|
1
|
78.41
|
<0.001
|
| RAM_BRD |
6.64
|
1
|
6.64
|
0.010
|
| EWE_BRD |
2.91
|
1
|
2.91
|
0.088
|
|
|
