University of Tehran Journal of Sciences, Islamic Republic of Iran 1016-1104 34 1 2023 03 01 Copula Functions for Spatial Survival Data Analysis 35 42 91395 10.22059/jsciences.2023.350366.1007763 EN Mohsen Mohammadzadeh 1 Department of Statistics‎, ‎Tarbiat Modares University‎, ‎Tehran‎, ‎Islamic Republic of Iran Nasrin Ebrahimi 1 Department of Statistics‎, ‎Tarbiat Modares University‎, ‎Tehran‎, ‎Islamic Republic of Iran Giuliana Cortese 2 Department of Statistical Sciences‎, ‎Padua University‎, ‎Italy Journal Article 2022 10 24 Many survival data analyses aim to assess the effect of different risk factors on survival time‎. ‎In some studies‎, ‎the survival times are correlated‎, ‎and the dependence between survival times is related to their spatial locations‎. ‎Identifying and considering the dependence structure of data is essential in survival modeling‎. ‎The copula functions are helpful tools for incorporating data dependencies‎. ‎So‎, ‎one may use these functions for modelling spatial survival data‎. ‎This paper presents a model for spatial survival data by the Gumbel-Hougaard copula function‎. ‎A two-stage estimator using a composite likelihood function is used to estimate regression and dependence parameters‎. ‎A simulation study investigates the performance of the model‎. ‎Finally‎, ‎the proposed model is applied to model a set of COVID-19 data.

https://jsciences.ut.ac.ir/article_91395_338043006bbb623f1bb07ac4c8f56564.pdf