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Event Probabilities Risks and Regression Methods
The occurrence of an event over time is often summarized by the incidence rate, defined as the average number of events per persontime. This type of rate applies to events that may occur repeatedly over time, such as headaches and infections. We developed nonparametric methods for obtaining incidence risks and regression methods for modeling the probability of events that can occur only once, such as death or first onset of a disease. 

Papers
Bottai M. A regression method for modelling geometric rates. Stat Methods Med Res. 2017, 26(6): 27002707 (first published 2015). Discacciati A, Bottai M. Instantaneous geometric rates via generalized linear models. Stata J. 2017, 17(2): 358371. Bottai M, Discacciati A, Santoni G. Defining and modeling the probability of occurrence of events. Working Paper 2020. Bottai M, Discacciati A, Santoni G. Modeling the probability of occurrence of events. Stat Methods Med Res. 2021 Aug;30(8):19761987. Bottai M. Estimating the risk of events with stprisk. Stata Journal (in press) Software Download the stprisk command in Stata: net install stprisk, from(http://www.imm.ki.se/biostatistics/stata) replace Download the stpreg command in Stata:net install stpreg, from(http://www.imm.ki.se/biostatistics/stata) replace Download the GLM links in Stata:net install st0478.pkg, from(http://www.statajournal.com/software/sj172/) Workedout example in Stata: Survival in metastatic renal carcinomaDownload the GLM links for R Workedout example in R: Survival in metastatic renal carcinoma 
Applications
Santoni G, Lagergren J, Bottai M. ASO Authors Reflections: Patient Age and Survival After Surgery for Esophageal Cancer. Ann Surg Oncol. 2020 May 29. doi: 10.1245/s1043402008661w. Lagergren J, Bottai M, Santoni G. Patient Age and Survival After Surgery for Esophageal Cancer. Ann Surg Oncol. 2020 May 28. doi: 10.1245/s1043402008653w. Presentations August 30, 2019 Instantaneous geometric rates via generalized linear models 2017 Nordic and Baltic Stata Users Group Meeting, Stockholm, Sweden September 1, 2017 Modeling the probability of occurrence of events with the new stpreg command 2019 Nordic and Baltic Stata Users Group Meeting, Stockholm, Sweden July 15, 2016 Regression modeling of geometric rates Workshop on Recent Advances in Quantile and Mquantile Regression, Pisa, Italy September 4, 2015 The grreg command for estimating geometric rate regression 2015 Nordic and Baltic Stata Users Group Meeting, Stockholm, Sweden March 16, 2015 Modeling geometric rates with quantile regression Swedish Statistical Society Annual Meeting, Stockholm, Sweden January 15, 2015 Modeling geometric rates with quantile regression Dep. Mathematics, University of Cagliari, Italy 
Unit of Biostatistics, Nobels väg 13, Karolinska Institutet, 17177 Stockholm, Sweden 