 <span class="c1"># todo this won't work for in-sample predictions</span>
        <span class="n">arma_pred</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">arma_</span><span class="o">.</span><span class="n">forecast</span><span class="p">(</span><span class="n">steps</span><span class="o">=</span><span class="n">estimator_pred</span><span class="o">.</span><span class="n">shape</span><span class="p">[</span><span class="mi">0</span><span class="p">])</spa