Browsing NTNU Open by Author "Lindqvist, Bo Henry"
Now showing items 1-20 of 47
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A Class of Tests for Trend in Time Censored Recurrent Event Data
Kvaløy, Jan Terje; Lindqvist, Bo Henry (Journal article; Peer reviewed, 2019)Statistical tests for trend in recurrent event data not following a Poisson process are generally constructed for event censored data. However, time censored data are more frequently encountered in practice. In this article, ... -
A simulation of the development and screening of Cancer Mammae
Riksheim, Marianne (Master thesis, 2009)Based on the tumor growth model of Harald Weedon-Fekjær et al.'s paper "Breast cancer tumor growth estimated through mammography screening data", a simulation of breast cancer occurrence and tumor growth in a large population ... -
A Simulation-based Approach for Exploring the Degradation and Maintenance of a Single-unit System
Farestveit, Odd Eirik (Master thesis, 2015)A model for degradation and maintenance of a single-item system is extensively studied in this thesis, using a simulation based approach. Stochastic processes are used as degradation models and the item is maintained ... -
Analysis of Life Regression Models for Censored Data using Pseudo Observations
Braarud, Ida Hakavik (Master thesis, 2013)Censoring is a common form for missing data in survival analysis. When a data set is censored, there is only partial knowledge of the survival time of some of the study units. To compensate for this, special techniques and ... -
Assessing short-term risk of ischemic stroke in relation to all prescribed medications
Janszky, Imre; Vardaxis, Ioannis; Lindqvist, Bo Henry; Horn, Jens; Brumpton, Ben Michael; Strand, Linn Beate; Bakken, Inger Johanne Landsjøåsen; Alsnes, Ingvild Vatten; Romundstad, Pål Richard; Ljung, Rickard; Mukamal, Kenneth J.; Sen, Abhijit (Peer reviewed; Journal article, 2021)We examined the short-term risk of stroke associated with drugs prescribed in Norway or Sweden in a comprehensive, hypothesis-free manner using comprehensive nation-wide data. We identified 27,680 and 92,561 cases with a ... -
Bayesianske nettverk kontra Monte Carlo simulering for estimering av produksjonsregularitet
Børsting, Aud (Master thesis, 2009)Denne masteroppgaven omhandler hvordan Bayesianske nettverk og Monte Carlo simulering kan bli brukt til å estimere produksjonsregulariteten til et system. De to metodene blir også sammenlignet med hverandre. Sammenligningen ... -
Betydning av feilspesifisert underliggende hasard for estimering av regresjonskoeffisienter og avhengighet i frailty-modeller
Mortensen, Bjørnar Tumanjan (Master thesis, 2007)Med levetidsdata for et stort antall familier kan man bruke frailty-modeller til å finne risikofaktorer og avhengighet innad i familien. En måte å gjøre dette på er å anta en realistisk fordeling for frailty-variabelen og ... -
Competing Risks Modeling by Extended Phase-Type Semi-Markov Distributions
Garcia-Maya, Brenda; Limnios, N.; Lindqvist, Bo Henry (Peer reviewed; Journal article, 2021)We present competing risks models within a semi-Markov process framework via the semi-Markov phase-type distribution. We consider semi-Markov processes in continuous and discrete time with a finite number of transient ... -
Condition monitoring and failure prediction in complex systems
Presthus, Gunnhild Hardersen (Master thesis, 2014)We consider a monitored system W(t) at time t which is modeled by a stochastic process. Failure of the system is connected to the process overreaching a certain threshold. The system is governed by an unobservable marker ... -
Conditional fiducial models
Taraldsen, Gunnar; Lindqvist, Bo Henry (Journal article; Peer reviewed, 2017)The fiducial is not unique in general, but we prove that in a restricted class of models it is uniquely determined by the sampling distribution of the data. It depends in particular not on the choice of a data generating ... -
Conditional Monte Carlo revisited
Lindqvist, Bo Henry; Erlemann, Rasmus; Taraldsen, Gunnar (Peer reviewed; Journal article, 2021)Conditional Monte Carlo refers to sampling from the conditional distribution of a random vector X given the value T ( X ) = t for a function T ( X ) . Classical conditional Monte Carlo methods were designed for estimating ... -
Conditional Sampling from a Gamma Distribution given Sufficient Statistics
Fagerland, Marius (Master thesis, 2016)This thesis is an analysis of conditional sampling from a gamma distribution given sufficient statistics. Several sampling algorithms are considered. An algorithm similar to direct sampling is discussed in particular. This ... -
Discussion of "Virtual age, is it real?"
Lindqvist, Bo Henry (Peer reviewed; Journal article, 2020)I congratulate the authors on this very interesting article discussing various aspects of the virtual age concept, which has been in active use in reliability and lifetime analyses for at least three decades. At the same ... -
Discussion of ‘Nonparametric generalized fiducial inference for survival functions under censoring’
Taraldsen, Gunnar; Lindqvist, Bo Henry (Journal article; Peer reviewed, 2019)The following discussion is inspired by the paper Nonparametric generalized fiducial inference for survival functions under censoring by Cui and Hannig. The discussion consists of comments on the results, but also indicates ... -
End of performance prediction of lithium-ion batteries
Wang, Yi-Fu; Tseng, Sheng-Tsaing; Lindqvist, Bo Henry; Tsui, Kwok-Leung (Journal article; Peer reviewed, 2019)Rechargeable batteries are critical components for the performance of portable electronics and electric vehicles. The long-term health performance of rechargeable batteries is characterized by state of health, which can ... -
Exact Statistical Inference in Nonhomogeneous Poisson Processes, based on Simulation
Rannestad, Bjarte (Master thesis, 2007)We present a general approach for Monte Carlo computation of conditional expectations of the form E[(T)|S = s] given a sufficient statistic S. The idea of the method was first introduced by Lillegård and Engen [4], and has ... -
Exact Statistical Inference in Parametric Models - Methods for Constructing Confidence Intervals and Confidence Regions Based on Conditional Parametric Bootstrap and Data Depth
Sektnan, Audun (Master thesis, 2017)In this Master's thesis we investigate approaches for constructing approximate and exact confidence intervals and regions in parametric models. A supposedly exact method, called conditional parametric bootstrap, is used ... -
Functional form for covariates in parametric accelerated failure time models using nonparametric exponential regression
Blindheimsvik, Martin (Master thesis, 2019)Denne oppgaven undersøker hvordan funksjonell formen til en potensielt misspesifisert kovariat i en akselerert levetids modell kan bli estimert ved hjelp av to forskjellige metoder anvendt på Cox-Snell residualene til ... -
Generative Adverseriale Nettverk (GAN) utvidelser og anvendelser innen bildeprosessering og generering
Sørby, Anders Christiansen (Master thesis, 2019)Når menneskehjernener prosesserer input fra sansene er de i stand til å unastrengt forestille seg nye instanser og scenarioer fra bare en liten mengde inputopplevelse. Generative Adverseriale Nettverk (GAN) klarer til en ... -
Imperfect Testing and its Influence on Availability of Safety Instrumented Systems
Sachdeva, Shipra (Master thesis, 2015)Imperfect testing of SIS, its types, definitions and models that take in account its contribution to average unavailability of the system.