Early Estimation of Microlensing Event Magnifications
  Gravitational microlensing events with high peak magnifications provide a much enhanced sensitivity to the detection of planets around the lens star. However, estimates of peak magnification during the early stages of an event by means of chi^2 minimization frequently involve an overprediction, making observing campaigns with strategies that rely on these predictions inefficient.   I show that a rudimentary Bayesian formulation, incorporating the known statistical characteristics of a detection system, produces much more accurate predictions of peak magnification than chi^2 minimisation. Implementation of this system will allow efficient follow-up observing programs that focus solely on events that contribute to planetary abundance statistics. 
Michael D. Albrow (1) ((1) Department of Physics and Astronomy,   University of Canterbury)