Research

Interests

I'm primarily interested in the statistical analysis of planar point patterns in space and space-time. Recent collaborations have also piqued an interest in developing Bayesian models for spatially varying phenomena. Much of my work falls under the umbrella of our informal research network -- Spatial Analysis Group Otago (SAGO). A full list of my peer-reviewed journal publications can be found further below. Specifically, my areas of research include:

• Kernel smoothing and density-ratios 

• Computational statistics, R programming

• Planar point patterns and spatial statistics

• Applications in geographical epidemiology and biology

If you have a strong academic record and are interested in working with me as a postgraduate student on topics related to the above, get in touch.

Grants/Awards

• 2019: Principal Investigator, Marsden Fund (Royal Society of New Zealand) Grant 19-UOO-191. "A new generation of statistical models for spatial point process data". Associate Investigators Prof Adrian Baddeley (Curtin University, Australia) and Prof Martin Hazelton (University of Otago, NZ). NZ$705,000; March 2020 - March 2023.

• 2017: Early Career Award for Distinction in Research, University of Otago

• 2015: Principal Investigator, Marsden Fund (Royal Society of New Zealand) Fast-start Grant 15-UOO-092. "Smoothing and inference for point process data with applications to epidemiology". Associate Investigators Dr Ben Taylor (Lancaster University, UK) and Prof Martin Hazelton (University of Otago, NZ). NZ$300,000; March 2016 - March 2019.

• 2014: Worsley Early Career Research Award, New Zealand Statistical Association (NZSA)

• 2012: Principal Investigator, University of Otago Research Grant-in-aid: "Statistical Methods for Spatial Intensity Estimation and their Performance in Epidemiology". NZ$5,700; Jan 2013 - Dec 2013.

Publications

To request copies of my published articles for scholarly research, send me an email.

Under review

• --

Published

2023

• Macdonald BJ, Davies TM, Hazelton ML (2023) Feasibility of Monte-Carlo maximum likelihood for fitting spatial log-Gaussian Cox processes, Spatial Statistics, {to appear}.

• Redmond AK, Davies TM, Schofield MR, Sheard PW (2023) New tools for investigation of muscle fiber-type spatial distributions across histological sections, Skeletal Muscle 13 7 1-11.

2022

• Baddeley A, Davies TM, Hazelton ML, Rakshit S, Turner R (2022) Fundamental problems in fitting spatial cluster process models, Spatial Statistics 52 100709.

• Baddeley A, Davies TM, Rakshit S, Nair G, McSwiggan G (2022) Diffusion smoothing for spatial point patterns, Statistical Science 37 1 123-142.

• Crump JA, Davies TM (2022) Towards equitable scheduling of global health teleconferences: a spatial exploration of the world's population and health by time zone, BMJ Open 12 e056696.

• Davies TM, Banerjee S, Martin AP, Turnbull RE (2022) A nearest-neighbour Gaussian process spatial factor model for censored, multi-depth geochemical data, Journal of the Royal Statistical Society Series C (Applied Statistics) 71 4 1014-1043.

• Hazelton ML, Davies TM (2022) Pointwise comparison of two multivariate density functions, Scandinavian Journal of Statistics 49 4 1791-1810.

2021

• Baddeley A, Nair G, Rakshit S, McSwiggan G, Davies TM (2021) Analysing point patterns on networks -- a review, Spatial Statistics 42 100435.

• Elson R, Davies TM, Lake IR, Vivancos R, Blomquist PB, Charlett A, Dabrera G  (2021) The spatio-temporal distribution of COVID-19 infection in England between January and June 2020, Epidemiology and Infection 149 e73 1-6.

2020

• Elson R, Davies TM, Jenkins C, Vivancos R, O'Brien SJ, Lake IR (2020) Application of kernel smoothing to estimate the spatio-temporal variation in risk of STEC O157 in England, Spatial and Spatio-temporal Epidemiology 32 100305.

2019

• Davies TM, Lawson AB (2019) An evaluation of likelihood-based bandwidth selectors for spatial and spatiotemporal kernel estimates, Journal of Statistical Computation and Simulation 89 7 1131-1152.

• Davies TM, Schofield MR, Cornwall J, Sheard PW (2019) Modelling multilevel spatial behaviour in binary-mark muscle fibre configurations, Annals of Applied Statistics 13 3 1329-1347.

• Rakshit S, Davies TM, Moradi MM, McSwiggan G, Nair G, Mateu J, Baddeley A (2019) Fast kernel smoothing of point patterns on a large network using 2D convolution, International Statistical Review 87 3 531-556.

2018

• Davies TM, Baddeley A (2018) Fast computation of spatially adaptive kernel estimates, Statistics and Computing 28 4 937-956.

• Davies TM, Flynn CR, Hazelton ML (2018) On the utility of asymptotic bandwidth selectors for spatially adaptive kernel density estimation, Statistics & Probability Letters 138 75-81.

• Davies TM, Marshall JC, Hazelton ML (2018) Tutorial on kernel estimation of continuous spatial and spatiotemporal relative risk, Statistics in Medicine 37 7 1191-1221.

2017

2016

• Davies TM (2016) The Book of R: A First Course in Programming and Statistics, No Starch Press, San Francisco, USA; 832p.

• Davies TM, Jones K, Hazelton ML (2016) Symmetric adaptive smoothing regimens for estimation of the spatial relative risk function, Computational Statistics & Data Analysis 101 12-28.

• Davies TM, Sheard PW, Cornwall J (2016) Letter to the Editor: Comment on Makino et al. and observations on spatial modeling, Anatomical Science International 91 4 423-424.

2015

• Farrell S, Davies TM, Cornwall J (2015) Use of clinical anatomy resources by musculoskeletal outpatient physiotherapists in Australian public hospitals: A cross-sectional study, Physiotherapy Canada 67 3 273-279.

• Fletcher JGR, Stringer MD, Briggs CA, Davies TM, Woodley SJ (2015) CT morphometry of adult thoracic intervertebral discs, European Spine Journal 24 10 2321-2329.

• Smith BA, Davies TM, Higham CFW (2015) Spatial and social variables in the Bronze Age phase 4 cemetery of Ban Non Wat, Northeast Thailand, Journal of Archaeological Science: Reports 4 34 362-370.

• Taylor BM, Davies TM, Rowlingson BS, Diggle PJ (2015) Bayesian inference and data augmentation schemes for spatial, spatiotemporal and multivariate log-Gaussian Cox processes in R, Journal of Statistical Software 63 7 1-48.

2014

2013

• Cornwall J, Davies TM, Lees D (2013) Student injuries in the dissecting room, Anatomical Sciences Education 6 6 404-409.

• Davies TM (2013) Jointly optimal bandwidth selection for the planar kernel-smoothed density-ratio, Spatial and Spatio-temporal Epidemiology 5 1 51-65.

• Davies TM (2013) Scaling oversmoothing factors for kernel estimation of spatial relative risk, Epidemiological Methods 2 1 67-83.

• Davies TM, Bryant DJ (2013) On circulant embedding for Gaussian random fields in R, Journal of Statistical Software 55 9 1-21.

• Davies TM, Cornwall J, Sheard PW (2013) Modelling dichotomously marked muscle fibre configurations, Statistics in Medicine 32 24 4240-4258.

• Davies TM, Hazelton ML (2013) Assessing minimum contrast parameter estimation for spatial and spatiotemporal log-Gaussian Cox processes, Statistica Neerlandica 67 4 355-389.

• Taylor BM, Davies TM, Rowlingson BS, Diggle PJ (2013) lgcp - An R package for inference with spatial and spatiotemporal log-Gaussian Cox processes, Journal of Statistical Software 52 4 1-40.

• Zhang ZJ, Davies TM, Gao J, Wang Z, Jiang QW (2013) Identification of high-risk regions for schistosomiasis in the Guichi region of China: an adaptive kernel density estimation-based approach, Parasitology 140 7 868-875.

2012

• Zhang ZJ, Chen DM, Chen Y, Davies TM, Vaillancourt JP, Liu WB (2012) Risk signals of an influenza pandemic caused by highly pathogenic avian influenza subtype H5N1: Spatio-temporal perspectives, Veterinary Journal 192 3 417-421.

2011

• Davies TM, Hazelton ML, Marshall JC (2011) sparr: Analyzing spatial relative risk using fixed and adaptive kernel density estimation in R, Journal of Statistical Software 39 1 1-14.

• Sanson RL, Harvey N, Garner MG, Stevenson MA, Davies TM, Hazelton ML, O'Connor J, Dubé C, Forde-Folle KN, Owen K (2011) Foot-and-mouth disease model verification and 'relative validation' through a formal model comparison, OIE Scientific and Technical Review 30 2 527-540.

2010

• Davies TM, Hazelton ML (2010) Adaptive kernel estimation of spatial relative risk, Statistics in Medicine 29 23 2423-2437.

2009

• Hazelton ML, Davies TM  (2009) Inference based on kernel estimates of the relative risk function in geographical epidemiology, Biometrical Journal 51 1 98-109.