Graham

Associate Professor
Graham Hepworth


hepworth@unimelb.edu.au
(03) 8344 4796


Consulting

I have more than 30 years experience as a consulting statistician. I joined the Statistical Consulting Centre in 2000, having previously worked in the Victorian Department of Primary Industries. I have particular expertise and experience in the design and analysis of experiments, as well as in surveys and sampling.

I have undertaken projects across a wide range of fields, including medicine, dentistry, food science, education, law, ecology, languages, psychology, and especially plant and animal sciences. I have performed work for a wide range of state and federal government agencies, small and large businesses, and individual researchers.

I have a Bachelor of Science (Honours), Master of Science, and a PhD, all in mathematical statistics from the University of Melbourne. I am an active member and a past president of the Australasian Region of the International Biometric Society. I am an Accredited Statistician (AStat) of the Statistical Society of Australia

Some recent consulting projects include:

Teaching

I regularly teach the intensive short courses"Design and Analysis of Surveys" and "Design and Analysis of Experiments" to participants from a wide range of fields. These are courses I developed using my extensive experience in surveys and experiments, which help researchers apply sound statistical methods to their research in practical ways.I have also developed and taught specialist in-house courses, such as “Design and Analysis of Simulation Experiments” which was delivered to the Defence Science and Technology Group.

I have previously taught both undergraduate and Masters level courses. For a couple of years I taught the subject “Thinking and Reasoning with Data” to Master of Science students. Prior to that I developed and taught the subject “Experimental Design / Statistical Methods” to students studying agriculture, forestry, and related disciplines.

Research

I am an Associate Professor of Statistics in the School of Mathematics and Statistics. I have over 70 refereed publications, in a wide range of subject areas. My methodological research has been mainly in estimating proportions by group testing (pooled testing), and in confidence intervals for discrete data, especially in relation to the binomial parameter.

My collaborative research, much of which has arisen from consulting, has been in many fields, including animal reproduction, plant pathology, cardiac electrophysiology, dentistry, nursing, water use, compost science, ecology, entomology, veterinary science, and neurology.

Publications

G. Hepworth (2016).  Approximate bias of the estimated proportion in group testing.  Environmental and Ecological Statistics  DOI:10.1007/s10651-016-0358-7.

N. Tomkins, A.J. Parker, G. Hepworth & M.J. Callaghan (2016).  Nitrate supplementation has marginal effects on enteric methane production from Bos indicus steers fed Flinders grass (Iseilema spp.) hay, but elevates blood methaemoglobin concentrations.  Animal Production Science .DOI:10.1071/AN16002.

I. Benu, M.J. Callaghan, N. Tomkins, G. Hepworth,  L.A. Fitzpatrick & A.J. Parker (2015).  The effect of feeding frequency and dose rate of nitrate supplements on blood haemoglobin fractions in Bos indicus cattle fed Flinders grass (Iseilemia spp.) hay.  Animal Production Science  DOI 10.1071/AN14886.

M.A. Benvenutti, T.W. Coates, A. Imaz, T. Flesch, J. Hill, E. Charmley, G. Hepworth & D. Chen (2015).  The use of image analysis to determine the number and position of cattle at a water point.  Computers and Electronics in Agriculture 118:24–27.

K.A. Dres, G. Hepworth & R.K. Watson (2015).  Exact confidence intervals for proportions estimated by group testing with different group sizes.  Australian and New Zealand Journal of Statistics 57:501–516.

K. Harapas, R. Premier, B. Tomkins, G. Hepworth & S. Ajlouni (2015).  Shoot injury increases the level of persistence of Salmonella enterica serovar Sofia and Listeria innocua on Cos lettuce and of Salmonella enterica serovar Sofia on chive.  Journal of Food Protection 78:2150–2155.

U. Seneviratne, G. Hepworth, M. Cook & W. D’Souza.  Can EEG differentiate among syndromes in genetic generalized epilepsy?  Accepted for publication in Journal of Clinical Neurophysiology.

U. Seneviratne, G. Hepworth, M. Cook & W. D’Souza (2016).  Atypical EEG abnormalities in genetic generalized epilepsies.  Clinical Neurophysiology 127stron:214–220.

I. Benu, M.J. Callaghan, N. Tomkins, G. Hepworth,  L.A. Fitzpatrick & A.J. Parker (2015).  The effect of feeding frequency and dose rate of nitrate supplements on blood haemoglobin fractions in Bos indicus cattle fed Flinders grass (Iseilemia spp.) hay.  Animal Production Science  DOI 10.1071/AN14886.

M.A. Benvenutti, T.W. Coates, A. Imaz, T.Flesch, J. Hill, E. Charmley, G. Hepworth & D. Chen (2015).  The use of image analysis to determine the number and position of cattle at a water point.  Computers and Electronics in Agriculture 118:24–27.
K.A. Dres, G. Hepworth & R.K. Watson (2015).  Exact confidence intervals for proportions estimated by group testing with different group sizes.  Australian and New Zealand Journal of Statistics.  DOI 10.1111/j.1467-842X.XXX.

K. Harapas, R. Premier, B. Tomkins, G. Hepworth & S. Ajlouni (2015).  Shoot injury increases the level of persistence of Salmonella enterica serovar Sofia and Listeria innocua on Cos lettuce and of Salmonella enterica serovar Sofia on chive.  Journal of Food Protection 78:2150–2155.

Hepworth G & Watson RK. (2015) Revisiting retesting in the estimation of proportions by group testing. Communications in Statistics – Simulation and Computation.DOI 10.1080/03610918.2014.960725.

Benu I, Callaghan MJ, Tomkins N, Hepworth G, Fitzpatrick LA & Parker AJ. The effect of feeding frequency and dose rate of nitrate supplements on blood haemoglobin fractions in Bos indicus cattle fed Flinders grass (Iseilemia spp.) hay. Accepted for publication in Animal Production Science.

Seneviratne U, Hepworth G, Cook M & D’Souza W. Atypical EEG abnormalities in genetic generalized epilepsies. Accepted for publication in Clinical Neurophysiology.

Borromeo GL, Brand C, Clement JG, McCullough M, Crighton L, Hepworth G & Wark JD. (2014) A large case-control study reveals a positive association between bisphosphonate use and delayed dental healing and osteonecrosis of the jaw. Journal of Bone and Mineral Research 29:1363–1368.

Mok HF, Dassanayake KB, Hepworth G & Hamilton AJ. (2014) Field comparison and crop production modeling of sweet corn and silage maize (Zea mays L.) with treated urban wastewater and freshwater. Irrigation Science 32:351–368.

Muir AM, Vesk PA & Hepworth G. (2014) Reproductive trajectories over decadal time-spans after fire for eight obligate-seeder shrub species in south-eastern Australia. Australian Journal of Botany 62:369–378.

Hepworth G. (2013) Improved estimation of proportions using inverse binomial group testing. Journal of Agricultural, Biological and Environmental Statistics 18:102–119.

Karavarsamis, N, Robinson AP, Hepworth G, Hamilton AJ & Heard GW. (2013) Comparison of four bootstrap-based interval estimators of species occupancy and detection probabilities. Australian and New Zealand Journal of Statistics 55:235–252.

Kumar S, Walters T, Halloran K, Morton JB , Hepworth G, Wong C, Kistler PM, Sanders P & Kalman JM. (2013) Ten-year trends in the use of catheter ablation for treatment of atrial fibrillation versus the use of coronary intervention for the treatment of ischaemic heart disease in Australia. European Journal of Pacing, Arrhythmias and Cardiac Electrophysiology 15:1702–1709.

Murray CG, Kasel S, Loyn RH, Walsh CJ, Hepworth G & Hamilton AJ. (2013) Waterbird use of artificial wetlands in an Australian urban landscape. Hydrobiologia 716:131–146.

Way KA, Jimmieson NL, Bordia P & Hepworth G. (2013) Self-labelling versus behavioural experience of workplace bullying: differences in sector- and industry-level prevalence and sources. Journal of Health, Safety and Environment 29:83–102.

All Publications here.

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