Results 271 to 280 of about 328,314 (314)

Estimation of the Jump-Point in a Hazard Function

Economic Quality Control, 2003
Summary: We consider a piecewise constant hazard function with exactly one jump point, say \(\tau\). It uniquely determines an exponential distribution whose density features a discontinuity of the first kind at the change point \(\tau\). Assuming that \(\tau\) is the unknown parameter of interest, the maximum likelihood estimator is shown to be ...
Abdel-Aty, Yahia, Ferger, Dietmar
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On Proportional Hazard Functions

Technometrics, 1970
The purpose of this note is to establish and make precise the following proposition: The minimum of independent random variables X and Y is independent of the event X x) if P(X = x ...
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Antigenic diversity thresholds and hazard functions

Mathematical Biosciences, 1997
In this paper, we answer some points made in a recent paper by N.I. Stilianakis and coworkers on the antigenic diversity threshold model for acquired immune deficiency syndrome pathogenesis. An extended version of the model is then used to compute hazard functions for the human immunodeficiency virus incubation period that are in agreement with ...
May, Robert M., Stekel, Dov J., Nowak, Martin A.   +2 more
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Nonparametric estimation of discrete hazard functions

Lifetime Data Analysis, 1996
A smoothing procedure for discrete time failure data is proposed which allows for the inclusion of covariates. This purely nonparametric method is based on discrete or continuous kernel smoothing techniques that gives a compromise between the data and smoothness. The method may be used as an exploratory tool to uncover the underlying structure or as an
Tutz, Gerhard, Pritscher, Lisa
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Tests for Reversed Hazard Rate Function

Calcutta Statistical Association Bulletin, 2003
The reversed hazard rate Junction of a random variable, defined as tlw ratio of the density to its distribution function, plays an important role in analyzing left-censored data. In this paper we develop tests based on the empirical distribution function for an assigned reversed hazard rate function against a onesided alternative and two different ...
Nanda, Asok K., Paul, Prasanta
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Methods for comparing cumulative hazard functions in a semi‐proportional hazard model

Statistics in Medicine, 1992
AbstractGraphical methods based on the analysis of differences between log cumulative hazard functions are considered for a two‐group semi‐proportional hazard model which allows for interaction between treatments and covariates. Confidence procedures and test statistics that can be used to test for interaction and for main effects are developed.
D M, Dabrowska, K A, Doksum, N J, Feduska, R, Husing, P, Neville   +4 more
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Mathematical tools for hazard function analysis

Journal of Mathematical Psychology, 2003
A hazard function is a characterization of the risk of an event occurring at a given point, conditioned by the fact that the event has not already occurred. Given the important role of the hazard functions in the mathematical psychology, the paper deals with mathematical techniques apt to prove several properties of hazard functions.
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Hazardous Failure Rate of the Safety Function

2015
Quantitative assessment of safety function integrity against random failures is necessary assumption for railway signalling system acceptance and its implementation into operation. The railway signalling system can be modelled as continuous mode system and therefore the criterion for quantitative assessment safety integrity of safety function is ...
Karol Rástocný, Juraj Zdánsky
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Hazard Function Estimation Using B-Splines

Biometrics, 1995
A flexible parametric procedure is given to model the hazard function as a linear combination of cubic B-splines and to obtain maximum likelihood estimates from censored survival data. The approach yields smooth estimates of the hazard and survivorship functions that are intermediate in structure between strongly parametric and non-parametric models. A
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Hazard Function of a Random Time

2004
In this chapter, the problem of a quasi-explicit evaluation of various conditional expectations is studied in the case when the only filtration available in calculations is the natural filtration of a random time. At the intuitive level, we consider here an individual who is able to observe a certain random time τ, but has no access to any other ...
Tomasz R. Bielecki, Marek Rutkowski
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