1</span><span class="o">=</span><span class="n">y1</span><span class="p">,</span> <span class="n">y2</span><span class="o">=</span><span class="n">y2</span><span class="p">,</span> <span class="n">N1</span><span class="o">=</span><span class="n">N1</span><span class="p">,</span> <span class="n">N2</span><span class="o">=</span><span class="n">N2</span><span class="p">,</span> <span class="n">mu</span><span class="o">=</span><span class="mi">0</span><span class="p">,</span> <span class="n">sigma</span><span 