maximum likelihood solution of 2 will yield the same solution u03b2 as 1 with the optimum value of u03c3 equal to the standard deviation of the measurements y i the optimum parameter set for the truncated problem is obtained by maximizing the log of the likelihood l l u03c3 i log 2 u03c0 u03c3 u2212 1 2 u2212 u03c3 i y i u2212 x i u03b2 2 2 u03c3 2 u2212 u03c3 i log u03c6 c i u2212 x i u03b2 u03c3 u2212 u03c3 i log u03c6 x i u03b2 u2212 d i u03c3 3 where y i x i u03c3 and a are as in 2 the c i are the upper truncation values the d i are the lower truncation values and u03c6 is the standard normal distribution function censored data can be generated from cw data by using the positions of points where the measurement falls below the sensitivity limit of the receiver left censored observations or above the receiver 39 s linear range right censored observations censored data is generated from scanner data in the same way but the lower limit is usually determined by the measured interference at each point the lower censoring level at a point in the.