Creating bounding box of an ofxAssimpModel

I found the methods for getSceneMin, getSceneMax, etc, and although they definitely seem to relate, they don't seem to really find the extremities properly. Partly because I don't understand the role of "scene" to ofxAssimpModelLoader. I also can see the methods getBoundingBoxWithMinVector and getBoundingBoxForNode, both of which I have no clue what to pass into to make work.