title: Multivariate Linear Mixed Model in lme4
body: <p>I wonder how to fit multivariate linear mixed model with <code>lme4</code>. I fitted univariate linear mixed models with the following code:</p>
  
  <pre><code>library(lme4)
  lmer.m1 &lt;- lmer(Y1~A*B+(1|Block)+(1|Block:A), data=Data)
  summary(lmer.m1)
  anova(lmer.m1)
  
  lmer.m2 &lt;- lmer(Y2~A*B+(1|Block)+(1|Block:A), data=Data)
  summary(lmer.m2)
  anova(lmer.m2)
  </code></pre>
  
  <p>I'd like to know how to fit multivariate linear mixed model with <code>lme4</code>. The data is below:</p>
  
  <pre><code>Block A B    Y1    Y2
   1    1 1 135.8 121.6
   1    1 2 149.4 142.5
   1    1 3 155.4 145.0
   1    2 1 105.9 106.6
   1    2 2 112.9 119.2
   1    2 3 121.6 126.7
   2    1 1 121.9 133.5
   2    1 2 136.5 146.1
   2    1 3 145.8 154.0
   2    2 1 102.1 116.0
   2    2 2 112.0 121.3
   2    2 3 114.6 137.3
   3    1 1 133.4 132.4
   3    1 2 139.1 141.8
   3    1 3 157.3 156.1
   3    2 1 101.2  89.0
   3    2 2 109.8 104.6
   3    2 3 111.0 107.7
   4    1 1 124.9 133.4
   4    1 2 140.3 147.7
   4    1 3 147.1 157.7
   4    2 1 110.5  99.1
   4    2 2 117.7 100.9
   4    2 3 129.5 116.2
  </code></pre>
  
  <p>Thank in advance for your time and cooperation.</p>