anchor.diff:      <td>Training</td>
       <td>
         <select id="select-training">
  -        <%= @trainings.each do |asm| %>
  +        <%= @course.trainings.each do |asm| %>
               <option value="<%= course_stats_training_path(@course, asm) %>"><%= asm.title %></option>
           <% end %>
         </select>
  
positive.code: </table>
  <!-- A graph to show statistical exp -->
  
  
negative.code:     <td>Mission</td>
      <td>
        <select id="select-mission">
          <%= @course.missions.each do |asm| %>
              <option value="<%= course_stats_mission_path(@course, asm) %>"><%= asm.title %></option>
          <% end %>
        </select>
  