.</span>
<span class="r-out co"><span class="r-pr">#&gt;</span>  $ group     : chr [1:136] "group_a" "group_a" "group_a" "group_a" ...</span>
<span class="r-out co"><span class="r-pr">#&gt;</span>  $ minute    : num [1:136] 0.01 10 20 45 60 75 90 105 120 140 ...</span>
<span class="r-out co"><span class="r-pr">#&gt;</span>  $ pdr       : num [1:136] 0 1.11 2.86 4.87 5.19 ...</span>
<span class="r-in"><span> <span class="co"># If you want data only, use null_fit()</span></span></span>
<span class="r-in"><spa