Maximum likelihood estimation and search. (A) Log likelihoods over different values of (the es-timate of α) and AA,AB (the estimate of GAA,BB, the probability that the control genotype is AA and the disease genotype is AB). The surface graph shows that likelihoods are maximized around the true α values (10% (left), 50% (middle), 90% (right)). (B) Search paths using the feasible direction method on contour maps. The method efficiently finds the optimum points (green circles) in only a few search steps. Searches from different starting points (blue circles) finally converge.