The stretched exponential
The closeness of the approximation depends on the value of
If a single exponential provides a better fit, a criterion would be that T1 ≈ T2.
Out of the eight distributions, three, the Weibull, gamma and exponential provide a visually good fit to the ω values (Additional file 1, Figure S1).
com/), where it was found that a function representing the sum of 2 exponentials provided the closest match between the observed reciprocal dose for a given end point and that calculated using the model.
The mild solution of system (3.24) is the exponential stability in -moment and almost surely exponential stability provided that (3.25).
Thus, when, by virtue of Corollary 3.4, the mild solution of system (4.1) is exponential stability in mean square and almost sure exponential stability provided that the following inequality.
After excluding the bi-exponential model, analysis using Akaike Information Criteria showed that the stretched exponential model provided the better fit to the majority of pixels in 64 % of lesions.
By comparison with the cross-validated estimates between exponential and Weibull distributions, we could find that the cure survival CART with exponential distribution provided a better fit than that with Weibull distribution.
