 <code>sf</code> object. Note that to complete the join, the identifier (in this case <code>GTA06</code>) must be in the same format in both data frames:</p>
<div class="sourceCode" id="cb592"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb592-1"><a href="activity-13-area-data-v.html#cb592-1" tabindex="-1"></a>travel_time_car<span class="sc">$</span>GTA06 <span class="ot">&lt;-</span> <span class="fu">factor</span>(travel_time_car<span class="sc">$</span>GTA06)</span>
<span id="cb592-2"><a