Question: Insert a noise term in your EM line fitter, so that it is able to perform robust fits. What is the effect on the number of local minima? Notice that, if there is a low probability of a point arising from noise, most points will be allocated to lines, but the fits will often be quite poor; if there is a high probability of a point arising from noise, points will be allocated to lines only if they fit well. What is the effect of this parameter on the number of local minima?