Different non-parametric methods have been developed to estimate the probability density function as well as counting process intensities over the last few decades. In this paper, we propose a non-parametric method to estimate the counting process intensity using a sequence of real polynomials to smooth the non-parametric estimator of the cumulative intensity provided by Nelson and Aalen. The basic properties of the estimator are also discussed. The proposed model is applied to an oncology data of stage II colon cancer patients treated with adjuvant chemotherapy. The intensities of patients who received two different combinations of chemo drugs have been compared.

counting process, polynomial estimation, Nelson-Aalen estimator, multiplicative intensity model, smoothing parameter.

Received: March 18, 2021; Accepted: May 17, 2021; Published: June 2, 2021

How to cite this article: Ratheesan K. and Anilkumar P., Smoothing intensities of counting process by using polynomial, JP Journal of Biostatistics 18(2) (2021), 209-230. DOI: 10.17654/JB018020209

This Open Access Article is Licensed under Creative Commons Attribution 4.0 International License

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