Allow for upwards Notches

[trilnick]

This was specifically requested. This also could have real life implications which seem more plausible to exist in the data: think of a high bonus after working more than X hours. If people can alter X, nobody would want miss X by an hour. Here, people bunch from the lower side, not the higher, but the process should be very similar. In fact, it might be feasible to do with just flipping the signs on some of the variables.