Identi cation of Prognostic Factors
نویسندگان
چکیده
A major issue in the analysis of diseases is the identiication and assessment of prognostic factors relevant to the development of the illness. Statistical analyses within the proportional hazards framework suuer from a lack exibility due to stringent model assumptions such as additivity and time{constancy of eeects. In this paper we use tree based models and varying coeecient models to allow for detectability of prognostic factors with possibly nonadditive, nonlinear and time{varying impact on disease development. Questions concerning model and smoothing{parameter selection are addressed. An analysis of a dataset of breast cancer patients demonstrates the ability of these methods to reveal additional insight into the disease innuencing mechanisms.
منابع مشابه
SECURING INTERPRETABILITY OF FUZZY MODELS FOR MODELING NONLINEAR MIMO SYSTEMS USING A HYBRID OF EVOLUTIONARY ALGORITHMS
In this study, a Multi-Objective Genetic Algorithm (MOGA) is utilized to extract interpretable and compact fuzzy rule bases for modeling nonlinear Multi-input Multi-output (MIMO) systems. In the process of non- linear system identi cation, structure selection, parameter estimation, model performance and model validation are important objectives. Furthermore, se- curing low-level and high-level ...
متن کاملIdenti cation of normalized coprime plant factors from closed loop
Recently introduced methods of iterative identi cation and control design are directed towards the design of high performing and robust control systems. These methods show the necessity of identifying approximate models from closed loop plant experiments. In this paper a method is proposed to approximately identify normalized coprime plant factors from closed loop data. The fact that normalized...
متن کاملIdentification and Control of a Compact Disc Mechanism Using Fractional Representations
This paper discusses the approximate and feedback relevant parametric identi cation of the radial servo system present in a Compact Disc player. In this application the problem of approximate identi cation based on data from closed loop experiments will be analyzed to nd a nite dimensional linear time invariant discrete time model, suitable for model-based control design. The feedback relevant ...
متن کاملObserver/Kalman Filter Identi cation for Online System Identi cation of Aircraft
The observer/Kalman lter identi cation method is applied to the problem of online system identi cation of accurate, locally linear, aircraft dynamicmodelsof nonlinearaircraft. It is a time-domaintechnique that identi es a discrete input–outputmapping from known input and outputdata samples,withoutuser imposed a priori assumptions aboutmodel structure or model order. The basic formulation o...
متن کاملInvestigating Open-World Person Re-identi cation Using a Drone
Person re-identi cation is now one of the most topical and intensively studied problems in computer vision due to its challenging nature and its critical role in underpinning many multi-camera surveillance tasks. A fundamental assumption in almost all existing re-identi cation research is that cameras are in xed emplacements, allowing the explicit modelling of camera and inter-camera properties...
متن کامل