The Lorentzian distribution. The graph shows the t probability distribution for 1, 4, 10 and infinite degrees of freedom. The distribution with 1 df is also known as the Lorentzian or Cauchy distribution. Our robust curve fitting method assumes that scatter follows this distribution.
Motulsky and Brown BMC Bioinformatics 2006 7:123 doi:10.1186/1471-2105-7-123