43 research outputs found
Multiple outlier detection tests for parametric models
We propose a simple multiple outlier identification method for parametric
location-scale and shape-scale models when the number of possible outliers is
not specified. The method is based on a result giving asymptotic properties of
extreme z-scores. Robust estimators of model parameters are used defining
z-scores. An extensive simulation study was done for comparing of the proposed
method with existing methods. For the normal family, the method is compared
with the well known Davies-Gather, Rosner's, Hawking's and Bolshev's multiple
outlier identification methods. The choice of an upper limit for the number of
possible outliers in case of Rosner's test application is discussed. For other
families, the proposed method is compared with a method generalizing
Gather-Davies method. In most situations, the new method has the highest
outlier identification power in terms of masking and swamping values. We also
created R package outliersTests for proposed test
Statistical analysis of the generalized additive semiparametric survival model with random covariate
Generalizations of the additive hazards model are considered. Estimates of the regression parameters and baseline function are proposed, when covariates are random. The asymptotic properties of estimators are considered
Bolshev's method of confidence limit construction
Confidence intervals and regions for the parameters of a distribution are constructed, following the method due to L. N. Bolshev. This construction method is illustrated with Poisson, exponential, Bernouilli, geometric, normal and other distributions depending on parameters
Non-parametric tests for censored data/ Bagdonavicius
xviii, 233 hal.: tab.; 24 cm
Non-parametric tests for censored data/ Bagdonavicius
xviii, 233 hal.: tab.; 24 cm
Statistical analysis of survival and reliability data with multiple crossing of survival functions
The so-called MCE model with possible multiple crossing of survival functions is studied. Under this model the ratios of the hazard rates increase, decrease or are constant, the hazard rates and the survival functions do not intersect, intersect once or twice
On goodness-of-fit for homogeneity and proportional hazards, by V.Bagdonavicius and M.Nikulin
The classical goodness-of-fit tests for homogeneity and proportional hazards have small power in the case of alternatives when crossings of survival functions are possible. We give test statistics which are oriented against wide classes of alternatives including possible crossings of survival functions. The limit distributions of the test statistics are derived
Estimation of reliability using failure-degradation data with explanatiry variable.
Semiparametric estimation od degradation and failure process characteristics using degradation and multi-mode failure data with covariates is considered supposing that the component of hazard rate related with observable degradation is unknown function of degradation and may depend on covariates
Accelerated Life Testing
The properties of important class of reliability models are considered
Aging and degradation models in reliability and safety
The models describing dependance of thelifetime distribution on the time-depending explanatory variables are considered. Such models are useful in reliability and survival analysis to study the reliability of bio-medical systems