Fit Validation Study – Low statistics example
{"Image DocumentName": "Fit Validation Study \u2013 Low statistics example", "Image ImageDescription": "Special care should be taken when fitting small data samples. Also if fitting for small signal component in large sample. Possible causes of trouble. c2 estimators may become approximate as Gaussian approximation of Poisson statistics becomes inaccurate. ML estimators may no longer be efficient \uf0e0 error estimate from 2nd derivative may become inaccurate. Bias term proportional to 1/N of ML and c2 estimators may no longer be small compared to 1/sqrt(N) In general, absence of bias, correctness of error can not be assumed. How to proceed? Use unbinned ML fits only \u2013 most robust at low statistics. Explicitly verify the validity of your fit. Wouter Verkerke, UCSB.", "Image XResolution": "37", "Image YResolution": "37", "Image ResolutionUnit": "Pixels/Centimeter", "Image Software": "SlidePlayer", "Image YCbCrPositioning": "Centered"}