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Faml: A Generic Metamodel For Mas Development, Ghassan Beydoun, Graham Low, Brian Henderson-Sellers, Haralambos Mouratidis, Jorge Gomez Sanz, Juan Pavon, Cesar Gonzalez-Perez Dec 2012

Faml: A Generic Metamodel For Mas Development, Ghassan Beydoun, Graham Low, Brian Henderson-Sellers, Haralambos Mouratidis, Jorge Gomez Sanz, Juan Pavon, Cesar Gonzalez-Perez

Associate Professor Ghassan Beydoun

In some areas of software engineering research, there are several metamodels claiming to capture the main issues. Though it is profitable to have variety at the beginning of a research field, after some time, the diversity of metamodels becomes an obstacle, for instance to the sharing of results between research groups. To reach consensus and unification of existing metamodels, metamodel-driven software language engineering can be applied. This paper illustrates an application of software language engineering in the agent-oriented software engineering research domain. Here, we introduce a relatively generic agent-oriented metamodel whose suitability for supporting modeling language development is demonstrated by …


Person-Level And Household-Level Regression Estimation In Household Surveys, David G. Steel, Robert Graham Clark Dec 2012

Person-Level And Household-Level Regression Estimation In Household Surveys, David G. Steel, Robert Graham Clark

Professor David Steel

A common class of survey designs involves selecting all people within selected households. Generalized regressionestimators can be calculated at either the person or household level. Implementing the estimator at the household level has the convenience of equal estimation weights for people within households. In this article the two approaches are compared theoretically and empirically for the case of simple random sampling of households and selection of all persons in each selected household. We find that the household level approach is theoretically more efficient in large samples and any empirical inefficiency in small samples is limited.


The Impact Of Complex Survey Design On Prevalence Estimates Of Intakes Of Food Groups In The Australian National Children’S Nutrition And Physical Activity Survey, Alexandra Burden, Yasmine Probst, David G. Steel, L. C. Tapsell Dec 2012

The Impact Of Complex Survey Design On Prevalence Estimates Of Intakes Of Food Groups In The Australian National Children’S Nutrition And Physical Activity Survey, Alexandra Burden, Yasmine Probst, David G. Steel, L. C. Tapsell

Professor David Steel

Objective: To assess the impact of the complex survey design used in the 2007 Australian National Children’s Nutrition and Physical Activity Survey (ANCNPAS) on prevalence estimates for intakes of groups of foods in the population of children. Design: The impacts on prevalence estimates were determined by calculating design effects for values for food group consumption. The implications of ignoring elements of the sample design including stratification, clustering and weighting were discussed. Setting: The 2007 ANCNPAS used a complex sample design involving stratification, a high degree of clustering and estimation weights. Subjects: Australian children aged 2-16 years. Results: Design effects ranging …


Updating The Dietadvice Website With New Australian Food Composition Data, Yasmine Probst, Holley-Anne Jones, Shannon Lin, S. Burden, David G. Steel, Linda C. Tapsell Dec 2012

Updating The Dietadvice Website With New Australian Food Composition Data, Yasmine Probst, Holley-Anne Jones, Shannon Lin, S. Burden, David G. Steel, Linda C. Tapsell

Professor David Steel

DietAdvice is an Australian self-administered dietary assessment website initially developed in 2003- 2005. The website allows patients to enter their dietary information and dieticians to remotely access and interpret the data. DietAdvice is presently being updated with new Australian food composition data. This study aims to describe the update process for moving from 1995 to 2006 food composition data. The database for the website was developed using grouped food data from the NUTTAB 1995 database. All food groups were cross-matched with the food from the NUTTAB 2006 database using the food ID codes. Rules were applied to determine the suitability …


Contextual Effects In Modeling For Small Domains, Mohammad-Reza Namazi-Rad, David G. Steel Dec 2012

Contextual Effects In Modeling For Small Domains, Mohammad-Reza Namazi-Rad, David G. Steel

Professor David Steel

During last two decades, different Small Area Estimation (SAE) methods have been proposed to overcome the challenge of finding reliable small area estimates. This happens a lot that the required data for various research purposes are available at different levels. Based on availability of data, individual-level or aggregated-level models are implied in SAE. However, the estimated values for model parameters obtained from individual-level analysis can be different from the one obtained based on analysis of aggregate data. Generally, this is referred to as the ecological fallacy. This happens due to some substantial contextual or area-level effects in the covariates. To …


The 2003 Australian Breast Health Survey: Survey Design And Preliminary Results, Elmer V. Villanueva, Sandra C. Jones, Caroline Nehill, Simone K. Favelle, David G. Steel, Don Iverson, Helen Zorbas Dec 2012

The 2003 Australian Breast Health Survey: Survey Design And Preliminary Results, Elmer V. Villanueva, Sandra C. Jones, Caroline Nehill, Simone K. Favelle, David G. Steel, Don Iverson, Helen Zorbas

Professor David Steel

The Breast Health Surveys, conducted by the National Breast Cancer Centre (NBCC) in 1996 and 2003, are designed to gain insight into the knowledge, attitudes and behaviours of a nationally representative sample of Australian women on issues relevant to breast cancer. In this article, we focus on major aspects of the design and present results on respondents' knowledge about mammographic screening. Methods: The 2003 BHS surveyed English-speaking Australian women aged 3069 without a history of breast cancer using computer-assisted telephone interviewing. Questions covered the following themes: knowledge and perceptions about incidence, mortality and risk; knowledge and behaviour regarding early detection, …


Contextual Effects In Modeling For Small Domain Estimation, Mohammad-Reza Namazi-Rad, David G. Steel Dec 2012

Contextual Effects In Modeling For Small Domain Estimation, Mohammad-Reza Namazi-Rad, David G. Steel

Professor David Steel

Many different Small Area Estimation (SAE) methods have been proposed to overcome the challenge of findingreliable estimates for small domains. Often, the required data for various research purposes are available at differentlevels of aggregation. Based on the available data, individual-level or aggregated-level models are used in SAE.However, parameter estimates obtained from individual and aggregated level analysis may be different, in practice.This may happen due to some substantial contextual or area-level effects in the covariates which may be misspecifiedin individual-level analysis. If small area models are going to be interpretable in practice, possible contextualeffects should be included. Ignoring these effects leads …


Understanding Ageing In Older Australians: The Contribution Of The Dynamic Analyses To Optimise Ageing (Dynopta) Project To The Evidence Base And Policy, Kaarin Anstey, Allison Blelak, Carole Birrell, Colette Browning, Richard Burns, Julie Byles, Kim Kiely, Binod Nepal, Lesley Ross, David Steel, Timothy Windsor Dec 2012

Understanding Ageing In Older Australians: The Contribution Of The Dynamic Analyses To Optimise Ageing (Dynopta) Project To The Evidence Base And Policy, Kaarin Anstey, Allison Blelak, Carole Birrell, Colette Browning, Richard Burns, Julie Byles, Kim Kiely, Binod Nepal, Lesley Ross, David Steel, Timothy Windsor

Professor David Steel

Aim:  To describe the Dynamic Analyses to Optimise Ageing (DYNOPTA) project and illustrate its contributions to understanding ageing through innovative methodology, and investigations on outcomes based on the project themes. DYNOPTA provides a platform and technical expertise that may be used to combine other national and international datasets. Methods:  The DYNOPTA project has pooled and harmonised data from nine Australian longitudinal studies to create the largest available longitudinal dataset (n= 50652) on ageing in Australia. Results:  A range of findings have resulted from the study to date, including methodological advances, prevalence rates of disease and disability, and mapping trajectories of …


Estimates Of Probable Dementia Prevalence From Population-Based Surveys Compared With Dementia Prevalence Estimates Based On Meta-Analyses, Kaarin J. Anstey, Richard A. Burns, Carole Birrell, David G. Steel, Kim M. Kiely, Mary A. Luszcz Dec 2012

Estimates Of Probable Dementia Prevalence From Population-Based Surveys Compared With Dementia Prevalence Estimates Based On Meta-Analyses, Kaarin J. Anstey, Richard A. Burns, Carole Birrell, David G. Steel, Kim M. Kiely, Mary A. Luszcz

Professor David Steel

Background: National data on dementia prevalence are not always available, yet it may be possible to obtain estimates from large surveys that include dementia screening instruments. In Australia, many of the dementia prevalence estimates are based on European data collected between 15 and 50 years ago. We derived populationbased estimates of probable dementia and possible cognitive impairment in Australian studies using the Mini-Mental State Examination (MMSE), and compared these to estimates of dementia prevalence from meta-analyses of European studies.

Methods: Data sources included a pooled dataset of Australian longitudinal studies (DYNOPTA), and two Australian Bureau of Statistics National …


Video-Recorded Usability Testing Of A Web-Based Self-Administered Dietary Assessment, Yasmine Probst, David Steel, Linda Tapsell Dec 2012

Video-Recorded Usability Testing Of A Web-Based Self-Administered Dietary Assessment, Yasmine Probst, David Steel, Linda Tapsell

Professor David Steel

No abstract provided.


Inclusion Of Mobile Phone Numbers Into An Ongoing Population Health Survey In Australia Using An Overlapping Dual Frame: Description Of Methods, Call Outcomes And Acceptance By Staff And Respondents, Margo Barr, Jason J. Van Ritten, David Steel, Sarah V. Thackway Dec 2012

Inclusion Of Mobile Phone Numbers Into An Ongoing Population Health Survey In Australia Using An Overlapping Dual Frame: Description Of Methods, Call Outcomes And Acceptance By Staff And Respondents, Margo Barr, Jason J. Van Ritten, David Steel, Sarah V. Thackway

Professor David Steel

In Australia telephone surveys has been the method of choice for ongoing population health surveys. Although it was estimated in 2011 that 20% of the population were mobile phone only persons the inclusion of mobile only phone users into these existing landline population health surveys has not occurred. This paper is part of a project that is looking in detail at the inclusion of mobile phone numbers into an ongoing population health survey in Australia. This paper describes the methods used, the call outcomes and acceptance by the population, supervisors and interviewing staff.


Measuring And Analyzing The Within Group Homogeneity Of Multi-Category Variables, David Steel, Mark Tranmer Dec 2012

Measuring And Analyzing The Within Group Homogeneity Of Multi-Category Variables, David Steel, Mark Tranmer

Professor David Steel

No abstract provided.


Unravelling Ecological Analysis, David Steel, Mark Tranmer, D Holt Dec 2012

Unravelling Ecological Analysis, David Steel, Mark Tranmer, D Holt

Professor David Steel

No abstract provided.


Investigation Of Relative Risk Estimates From Studies Of The Same Population With Contrasting Response Rates And Designs, Nicole M. Mealing, Emily Banks, Louisa R. Jorm, David G. Steel, Mark S. Clements, Kris D. Rogers Dec 2012

Investigation Of Relative Risk Estimates From Studies Of The Same Population With Contrasting Response Rates And Designs, Nicole M. Mealing, Emily Banks, Louisa R. Jorm, David G. Steel, Mark S. Clements, Kris D. Rogers

Professor David Steel

Background: There is little empirical evidence regarding the generalisability of relative risk estimates from studies which have relatively low response rates or are of limited representativeness. The aim of this study was to investigate variation in exposure-outcome relationships in studies of the same population with different response rates and designs by comparing estimates from the 45 and Up Study, a population-based cohort study (self-administered postal questionnaire, response rate 18%), and the New South Wales Population Health Survey (PHS) (computer-assisted telephone interview, response rate ~60%). Methods: Logistic regression analysis of questionnaire data from 45 and Up Study participants (n = 101,812) …


Fixed Rank Filtering For Spatio-Temporal Data, Noel Cressie, Tao Shi, Emily L. Kang Nov 2012

Fixed Rank Filtering For Spatio-Temporal Data, Noel Cressie, Tao Shi, Emily L. Kang

Professor Noel Cressie

Datasets from remote-sensing platforms and sensor networks are often spatial, temporal, and very large. Processing massive amounts of data to provide current estimates of the (hidden) state from current and past data is challenging, even for the Kalman filter. A large number of spatial locations observed through time can quickly lead to an overwhelmingly high-dimensional statistical model. Dimension reduction without sacrificing complexity is our goal in this article. We demonstrate how a Spatio-Temporal Random Effects (STRE) component of a statistical model reduces the problem to one of fixed dimension with a very fast statistical solution, a methodology we call Fixed …


Combining Outputs From The North American Regional Climate Change Assessment Program By Using A Bayesian Hierarchical Model, Emily L. Kang, Noel Cressie, Stephan R. Sain Nov 2012

Combining Outputs From The North American Regional Climate Change Assessment Program By Using A Bayesian Hierarchical Model, Emily L. Kang, Noel Cressie, Stephan R. Sain

Professor Noel Cressie

We investigate the 20-year-average boreal winter temperatures generated by an ensemble of six regional climate models (RCMs) in phase I of the North American Regional Climate Change Assessment Program. We use the long-run average (20-year integration) to smooth out variability and to capture the climate properties from the RCM outputs. We find that, although the RCMs capture the large-scale climate variation from coast to coast and from south to north similarly, their outputs can differ substantially in some regions. We propose a Bayesian hierarchical model to synthesize information from the ensemble of RCMs, and we construct a consensus climate signal …


Modeling Dynamic Controls On Ice Streams: A Bayesian Statistical Approach, L Mark Berliner, Kenneth Jezek, Noel Cressie, Yongku Kim, Calvin Lam, Cornelis Van Der Veen Nov 2012

Modeling Dynamic Controls On Ice Streams: A Bayesian Statistical Approach, L Mark Berliner, Kenneth Jezek, Noel Cressie, Yongku Kim, Calvin Lam, Cornelis Van Der Veen

Professor Noel Cressie

Our main goal is to exemplify the study of ice-stream dynamics via Bayesian statistical analysis incorporating physical, though imperfectly known, models using data that are both incomplete and noisy. The physical-statistical models we propose account for these uncertainties in a coherent, hierarchical manner. The initial modeling assumption estimates basal shear stress as equal to driving stress, but subsequently includes a random corrector process to account for model error. The resulting stochastic equation is incorporated into a simple model for surface velocities. Use of Bayes' theorem allows us to make inferences on all unknowns given basal elevation, surface elevation and surface …


A Method For Evaluating Bias In Global Measurements Of Co2 Total Columns From Space, D Wunch, P O. Wennberg, G C. Toon, B J. Connor, B Fisher, G B. Osterman, C Frankenberg, L Mandrake, C O'Dell, P Ahonen, S C. Biraud, R Castano, Noel Cressie, D Crisp, N M. Deutscher, A Eldering, M L. Fisher, David W. Griffith, M Gunson, P Heikkinen, G Keppel-Aleks, E Kyro, R Lindemaier, Ronald Macatangay, J Mendonca, J Messerschmidt, C E. Miller, I Morino, J Notholt, F A. Oyafuso, M Rettinger, J Robinson, C M. Roehl, R J. Salawitch, V Sherlock, K Strong, R Sussmann, T Tanaka, D R. Thompson, O Uchino, Thorsten Warneke, Steven C. Wofsy Nov 2012

A Method For Evaluating Bias In Global Measurements Of Co2 Total Columns From Space, D Wunch, P O. Wennberg, G C. Toon, B J. Connor, B Fisher, G B. Osterman, C Frankenberg, L Mandrake, C O'Dell, P Ahonen, S C. Biraud, R Castano, Noel Cressie, D Crisp, N M. Deutscher, A Eldering, M L. Fisher, David W. Griffith, M Gunson, P Heikkinen, G Keppel-Aleks, E Kyro, R Lindemaier, Ronald Macatangay, J Mendonca, J Messerschmidt, C E. Miller, I Morino, J Notholt, F A. Oyafuso, M Rettinger, J Robinson, C M. Roehl, R J. Salawitch, V Sherlock, K Strong, R Sussmann, T Tanaka, D R. Thompson, O Uchino, Thorsten Warneke, Steven C. Wofsy

Professor Noel Cressie

We describe a method of evaluating systematic errors in measurements of total column dry-air mole fractions of CO2 (XCO2) from space, and we illustrate the method by applying it to the v2.8 Atmospheric CO2 Observations from Space retrievals of the Greenhouse Gases Observing Satellite (ACOS-GOSAT) measurements over land. The approach exploits the lack of large gradients in XCO2 south of 25S to identify large-scale offsets and other biases in the ACOS-GOSAT data with several retrieval parameters and errors in instrument calibration. We demonstrate the effectiveness of the method by comparing the ACOS-GOSAT data in the Northern Hemisphere with ground truth …


Dynamical Random-Set Modeling Of Concentrated Precipitation In North America, Noel Cressie, Renato Assuncao, Scott H. Holan, Michael Levine, Orietta Nicolis, Jun Zhang, Jian Zou Nov 2012

Dynamical Random-Set Modeling Of Concentrated Precipitation In North America, Noel Cressie, Renato Assuncao, Scott H. Holan, Michael Levine, Orietta Nicolis, Jun Zhang, Jian Zou

Professor Noel Cressie

In order to study climate at scales where policy decisions can be made, regional climate models (RCMs) have been developed with much finer resolution (~50 km) than the ~500 km resolution of atmosphere-ocean general circulation models (AOGCMs). The North American Regional Climate Change Assessment Program (NARCCAP) is an international program that provides 50-km resolution climate output for the United States, Canada, and northern Mexico. In Phase I, there are six RCMs, from which we choose one to illustrate our methodology. The RCMs are updated every 3 hours and contain a number of variables, including temperature, precipitation, wind speed, wind direction, …


Rejoinder, Peter Craigmile, Catherine Caldert, Hongfei Li, Rajib Paul, Noel Cressie Nov 2012

Rejoinder, Peter Craigmile, Catherine Caldert, Hongfei Li, Rajib Paul, Noel Cressie

Professor Noel Cressie

We agree with Schmidt that it is essential that researchers from many diverse areas have access to affordable, but still trustworthy, software. In this research project, substantial effort went into preparing datasets. Much of the data came from different government agencies, with databases arranged in multiple formats, often including variables that were not immediately relevant to our scientific pursuits. In our work on this project, the use of SAS was essential to producing clean datasets.


Hierarchical Model Building, Fitting, And Checking: A Behind-The-Scenes Look At A Bayesian Analysis Of Arsenic Exposure Pathways, Peter F. Craigmile, Catherine A. Calder, Hongfei Li, Rajib Paul, Noel Cressie Nov 2012

Hierarchical Model Building, Fitting, And Checking: A Behind-The-Scenes Look At A Bayesian Analysis Of Arsenic Exposure Pathways, Peter F. Craigmile, Catherine A. Calder, Hongfei Li, Rajib Paul, Noel Cressie

Professor Noel Cressie

In this article, we present a behind-the-scenes look at a Bayesian hierarchical analysis of pathways of exposure to arsenic (a toxic heavy metal) using the Phase I National Human Exposure Assessment Survey carried out in Arizona. Our analysis combines individual-level personal exposure measurements (biomarker and environmental media) with water, soil, and air observations from the ambient environment. We include details of our model-building exercise that involved a combination of exploratory data analysis and substantive knowledge in exposure science. Then we present our strategies for model fitting, which involved piecing together components of the hierarchical model in a systematic fashion to …


Accounting For Uncertainty In Ecological Analysis: The Strengths And Limitations Of Hierarchical Statistical Modeling, Noel Cressie, Catherine Calder, James Clark, Jay Ver Hoef, Christopher Wikle Nov 2012

Accounting For Uncertainty In Ecological Analysis: The Strengths And Limitations Of Hierarchical Statistical Modeling, Noel Cressie, Catherine Calder, James Clark, Jay Ver Hoef, Christopher Wikle

Professor Noel Cressie

Analyses of ecological data should account for the uncertainty in the process(es) that generated the data. However, accounting for these uncertainties is a difficult task, since ecology is known for its complexity. Measurement and/or process errors are often the only sources of uncertainty modeled when addressing complex ecological problems, yet analyses should also account for uncertainty in sampling design, in model specification, in parameters governing the specified model, and in initial and boundary conditions. Only then can we be confident in the scientific inferences and forecasts made from an analysis. Probability and statistics provide a framework that accounts for multiple …


Spectral Density Estimation Through A Regularized Inverse Problem, Chunfeng Huang, Tailen Hsing, Noel Cressie Nov 2012

Spectral Density Estimation Through A Regularized Inverse Problem, Chunfeng Huang, Tailen Hsing, Noel Cressie

Professor Noel Cressie

In the study of stationary stochastic processes on the real line, the covariance function and the spectral density function are parameters of considerable interest. They are equivalent ways of expressing the temporal dependence in the process. In this article, we consider the spectral density function and propose a new estimator that is not based on the periodogram; the estimator is derived through a regularized inverse problem. A further feature of the estimator is that the data are not required to be observed on a grid. When the regularization condition is based on the function's first derivative, we give the estimator …


The Merits Of Racial Hatred Laws: Beyond Free Speech, Luke Mcnamara Nov 2012

The Merits Of Racial Hatred Laws: Beyond Free Speech, Luke Mcnamara

Luke McNamara

No abstract provided.


Recognition Of Indigenous Land Rights As Native Title: Continuity And Transformation, Luke Mcnamara, Donald Grattan Nov 2012

Recognition Of Indigenous Land Rights As Native Title: Continuity And Transformation, Luke Mcnamara, Donald Grattan

Luke McNamara

No abstract provided.


Aboriginal Human Rights And The Australian Criminal Justice System: Self-Determination As A Solution?, Luke Mcnamara Nov 2012

Aboriginal Human Rights And The Australian Criminal Justice System: Self-Determination As A Solution?, Luke Mcnamara

Luke McNamara

No abstract provided.


Criminalising Racial Hatred: Learning From The Canadian Experience, Luke Mcnamara Nov 2012

Criminalising Racial Hatred: Learning From The Canadian Experience, Luke Mcnamara

Luke McNamara

No abstract provided.


Criminal Laws: Materials And Commentary On Criminal Law And Process In Nsw, David Brown, David Farrier, Sandra Egger, Luke Mcnamara, Alex Steel Nov 2012

Criminal Laws: Materials And Commentary On Criminal Law And Process In Nsw, David Brown, David Farrier, Sandra Egger, Luke Mcnamara, Alex Steel

Luke McNamara

This third edition of Criminal Laws continues and extends the features that made the second edition the leading tertiary criminal law teaching and resource book in NSW and the ACT, highly influential in other states, and a must for practitioners working in criminal law.It combines: key primary materials for students, in the form of the leading cases and statutes; extracts from secondary literature, which provide context and commentary from a range of perspectives and disciplines; and extensive critical commentary by the authors.Criminal law is approached as a mode of regulation with specific limits, and a sceptical attitude is maintained to …


Introduction: The Protection Of Law, Luke Mcnamara Nov 2012

Introduction: The Protection Of Law, Luke Mcnamara

Luke McNamara

No abstract provided.


The Common Law Construct Of Native Title: A 'Re-Feudalisation' Of Australian Land Law, Scott Grattan, Luke Mcnamara Nov 2012

The Common Law Construct Of Native Title: A 'Re-Feudalisation' Of Australian Land Law, Scott Grattan, Luke Mcnamara

Luke McNamara

No abstract provided.