an class="st">"A:B"</span><span class="op">)</span></span></span>
<span class="r-out co"><span class="r-pr">#&gt;</span>       Y1   Y2</span>
<span class="r-out co"><span class="r-pr">#&gt;</span> 1:1  3.0 12.0</span>
<span class="r-out co"><span class="r-pr">#&gt;</span> 2:1 17.5 11.5</span>
<span class="r-out co"><span class="r-pr">#&gt;</span> 3:1 14.5 10.5</span>
<span class="r-out co"><span class="r-pr">#&gt;</span> 1:2 15.5 -3.5</span>
<span class="r-out co"><span class="r-pr">#&gt;</span> 2:2 19.5  0