Poisson Counts, Square Root Transformation and Small Area Estimation: Square Root Transformation.

Sankhya B (2008)

Institute of Mathematics for Industry, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka Japan.

Published: October 2021

The paper intends to serve two objectives. First, it revisits the celebrated Fay-Herriot model, but with homoscedastic known error variance. The motivation comes from an analysis of count data, in the present case, COVID-19 fatality for all counties in Florida. The Poisson model seems appropriate here, as is typical for rare events. An empirical Bayes (EB) approach is taken for estimation. However, unlike the conventional conjugate gamma or the log-normal prior for the Poisson mean, here we make a square root transformation of the original Poisson data, along with square root transformation of the corresponding mean. Proper back transformation is used to infer about the original Poisson means. The square root transformation makes the normal approximation of the transformed data more justifiable with added homoscedasticity. We obtain exact analytical formulas for the bias and mean squared error of the proposed EB estimators. In addition to illustrating our method with the COVID-19 example, we also evaluate performance of our procedure with simulated data as well.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8503421PMC
http://dx.doi.org/10.1007/s13571-021-00269-8DOI Listing

Publication Analysis

Top Keywords

square root
20
root transformation
20
poisson square
8
original poisson
8
transformation
6
poisson
5
square
5
root
5
poisson counts
4
counts square
4

Similar Publications

Purpose: The aim of the work is to develop a cascaded diffusion-based super-resolution model for low-resolution (LR) MR tagging acquisitions, which is integrated with parallel imaging to achieve highly accelerated MR tagging while enhancing the tag grid quality of low-resolution images.

Methods: We introduced TagGen, a diffusion-based conditional generative model that uses low-resolution MR tagging images as guidance to generate corresponding high-resolution tagging images. The model was developed on 50 patients with long-axis-view, high-resolution tagging acquisitions.

View Article and Find Full Text PDF

Association between weight-adjusted-waist index and long-term prognostic outcomes in cardiovascular disease patients: results from the NHANES 1999-2018 study.

Diabetol Metab Syndr

January 2025

Rehabilitation Medicine Center, Institute of Rehabilitation Medicine, West China Hospital, Sichuan University, Chengdu, 610041, China.

Background: As cardiovascular disease (CVD) morbidity and mortality increase yearly, this study aimed to explore the potential of the weight-adjusted-waist index (WWI) and its relation to long-term mortality in patients with CVD.

Methods: The diagnosis of CVD was based on standardized medical condition questionnaires that incorporated participants' self-reported physician diagnoses. WWI (cm/√kg) is a continuous variable and calculated as waist circumference (WC, cm) divided by square root of body weight (kg).

View Article and Find Full Text PDF

In clinical movement biomechanics, kinematic measurements are collected to characterise the motion of articulating joints and investigate how different factors influence movement patterns. Representative time-series signals are calculated to encapsulate (complex and multidimensional) kinematic datasets succinctly. Exacerbated by numerous difficulties to consistently define joint coordinate frames, the influence of local frame orientation and position on the characteristics of the resultant kinematic signals has been previously proven to be a major limitation.

View Article and Find Full Text PDF

Near-Field Clutter Mitigation in Speckle Tracking Echocardiography.

Ultrasound Med Biol

January 2025

Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong; Biomedical Engineering Programme, The University of Hong Kong, Hong Kong. Electronic address:

Objective: Near-field (NF) clutter filters are critical for unveiling true myocardial structure and dynamics. Randomized singular value decomposition (rSVD) stands out for its proven computational efficiency and robustness. This study investigates the effect of rSVD-based NF clutter filtering on myocardial motion estimation.

View Article and Find Full Text PDF

Leveraging the nanotopography of filamentous fungal chitin-glucan nano/microfibrous spheres (FNS) coated with collagen (type I) for scaffolded fibroblast spheroids in regenerative medicine.

Tissue Cell

January 2025

School of Chemical Engineering, Yeungnam University, 280 Daehak-Ro, Gyeongsan, Gyeongbuk 38541, Republic of Korea; Research Institute of Cell Culture, Yeungnam University, 280 Daehak-Ro, Gyeongsan, Gyeongbuk 38541, Republic of Korea. Electronic address:

Numerous naturally occurring biological structures have inspired the development of innovative biomaterials for a wide range of applications. Notably, the nanotopographical architectures found in natural materials have been leveraged in biomaterial design to enhance cell adhesion and proliferation and improve tissue regeneration for biomedical applications. In this study, we fabricated three-dimensional (3D) chitin-glucan micro/nanofibrous fungal-based spheres coated with collagen (type I) to mimic the native extracellular matrix (ECM) microenvironment.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!