BACKGROUND The current stopping rule for peginterferon/ribavirin therapy in hepatitis C virus genotype-1 (HCV-1) patients is based on an early virological response (EVR, defined as >2 log(10) viral reduction at treatment week 12). We aimed to explore rapid stopping rules at week 4. METHODS We randomly allocated 528 HCV-1 patients into training and validation sets (at a 1∶2 ratio). The interle...

In this paper, a traditional clustering algorithm based on speaker identification is presented. Several audio data sets were tested to conclude how accurate the clustering algorithm is depending on the characteristics of the analyzed database. We show that, issues such as the size of the database, the number speakers, or how the audios are balanced over the speakers in the database significantl...

We present a general analysis for the criteria to stop and store light coherently. We show that a light pulse can be stopped in any physical system, provided that (i) the system bandwidth can be compressed to zero; (ii) the system has sufficient degrees of freedom to accommodate the pulse, and the bandwidth compression occurs while the pulse is in the system; and (iii) the bandwidth compression...

In this paper, we investigate the convergence behaviour of a class of regularized Newton methods for the solution of nonlinear inverse problems. In order to keep the overall numerical effort as small as possible, we propose to solve the linearized equations by certain semiiterative regularization methods, in particular, iterations with optimal speed of convergence. Our convergence rate analysis...

We develop a Monte Carlo method to solve continuous-time adaptive disorder problems. An unobserved signal X undergoes a disorder at an unknown time to a new unknown level. The controller’s aim is to detect and identify this disorder as quickly as possible by sequentially monitoring a given observation process Y . We adopt a Bayesian setup that translates the problem into a two-step procedure of...

Given a random time, we give some characterizations of the set of martingales for which the stopping theorems still hold. We also investigate how the stopping theorems are modified when we consider arbitrary random times. To this end, we introduce some families of martingales with remarkable properties. DOI: https://doi.org/10.1016/j.spa.2006.06.005 Posted at the Zurich Open Repository and Arch...

Decision making from sequential sampling, especially when more than two alternative choices are possible, requires appropriate stopping criteria to maximize accuracy under time constraints. Optimal conditions for stopping have previously been investigated for modeling human decision making processes. In this work, we show how the k-nearest neighbor classification algorithm in machine learning c...

We consider two distinct centers which arise in measuring how quickly a random walk on a tree mixes. Lovász and Winkler [8] point out that stopping rules which “look where they are going” (rather than simply walking a fixed number of steps) can achieve a desired distribution exactly and efficiently. Considering an optimal stopping rule that reflects some aspect of mixing, we can use the expecte...

This paper deals with perturbed linear fixed point methods in the presence of round-off errors. Successive approximations as well as the more general asynchronous iterations are treated. Forward and backward error estimates are presented, and these are used to propose theoretical stopping criteria for these methods. In the case of asynchronous iterations, macro-iterations are used as a tool in ...

When using optimization algorithms the goal is usually clear: The global optimum should be found. However, in general it is not clear when this goal is achieved, especially if real-world problems are optimized for which no knowledge about the global optimum is available. Therefore, it is not easy to decide when the execution of an optimization algorithm should be terminated. Although different ...