span class="r-out co"><span class="r-pr">#&gt;</span>  (Intr) year group1 yr:gr1</span>
<span class="r-out co"><span class="r-pr">#&gt;</span>       0    0      1      0</span>
<span class="r-out co"><span class="r-pr">#&gt;</span>       0    0      0      1</span>
<span class="r-out co"><span class="r-pr">#&gt;</span> </span>
<span class="r-out co"><span class="r-pr">#&gt;</span>     Chisq df Pr(&gt;|Chi|)</span>
<span class="r-out co"><span class="r-pr">#&gt;</span>   18.7743  2      1e-04</span>
<span cl