Figure 3.

(A) Plot of the probability density function—gamma, inverse gamma, log-normal, inverse Gaussian—used throughout this paper to compute the oxygen extraction fraction (OEF) and other quantities derived from OEF. Relative dispersions r equal to 0.4 and 1.2 are considered. (B) Plot of the corresponding cumulative distribution functions, for relative dispersions r equal to 0.4, 1.2, and 3. For A and B, abscissae unit is expressed in terms of transit time normalized with respect to the mean transit time (MTT); and A's ordinate is expressed in terms of the product between the density of probability p and MTT.