Collada Joint Matrix - Which is Root joint matrix, Armature or Torso ?

I try to draw a bind pose but unsure which one is ROOT JOINT, Armature or Torso based on .DAE below ?

  <library_visual_scenes>
    <visual_scene id="Scene" name="Scene">
      <node id="Armature" name="Armature" type="NODE">
        <matrix sid="transform">1 0 0 0 0 1 0 0 0 0 1 0 0 0 0 1</matrix>
        <node id="Armature_Torso" name="Torso" sid="Torso" type="JOINT">
          <matrix sid="transform">1 0 0 0 0 0 -1 0 0 1 0 1.839252 0 0 0 1</matrix>
          <node id="Armature_Chest" name="Chest" sid …