Nick Fieller - Academia.edu (original) (raw)

Papers by Nick Fieller

Research paper thumbnail of Multivariate Outliers

Encyclopedia of Statistics in Behavioral Science, 2005

Research paper thumbnail of Cluster analysis

Cognitive Foundations of Language Structure and Use, 2014

Research paper thumbnail of Generation of Values for Missing

Computer-Aided Forensic Facial Comparison, 2010

Research paper thumbnail of Statistical Modelling and Computing

Much of the course will be focused around the computing system R which provides various statistic... more Much of the course will be focused around the computing system R which provides various statistical facilities including high quality graphics. It is an open source system and is available free. It is 'not unlike' the expensive commercial package S-PLUS, the prime difference is that R is command-line driven without the standard menus and dialog boxes in S-PLUS. Otherwise, most code written for the two systems is interchangeable.

Research paper thumbnail of From sand grains to tomatoes: applications of size distributions

Research paper thumbnail of Hilda M. Davies, 1914-2008

Journal of the Royal Statistical Society Series A (Statistics in Society)

Research paper thumbnail of Morris Walker, 1921-2010

Journal of the Royal Statistical Society Series A (Statistics in Society)

Research paper thumbnail of Multivariate Outliers

Wiley StatsRef: Statistics Reference Online, 2014

Research paper thumbnail of INFLUENCE FUNCTIONS IN FUNCTIONAL MEASUREMENT ERROR MODELS WITH REPLICATED DATA

Statistics, 2003

ABSTRACT We consider the construction and properties of influence functions in the context of fun... more ABSTRACT We consider the construction and properties of influence functions in the context of functional measurement error models with replicated data. In these models estimates of the parameters can be affected both by the individual observations and the means of replicated observations. We show that influence function of the means of replicates on the estimate of regression coefficients can be only derived under the assumption that the variances of the errors are known, while one for the individual observations can be only derived simultaneously with their influence function on the estimators of the variances of the errors.

Research paper thumbnail of Archaeostatistics: Old Statistics in Ancient Contexts

Research paper thumbnail of The Identification of Multiple Outliers: Comment

Journal of the American Statistical Association, 1993

Research paper thumbnail of Considerations of minimum numbers: a response to Horton

Journal of Archaeological Science, 1985

ABSTRACT This paper discusses a recent evaluation of bone assemblage quantification methods based... more ABSTRACT This paper discusses a recent evaluation of bone assemblage quantification methods based in large part upon a critique of our own published work. We aim to show that the critique reveals a misunderstanding of our proposals and of the aims of quantification techniques in this field.

Research paper thumbnail of Number estimation in vertebrate samples

Journal of Archaeological Science, 1982

ABSTRACT Methods of quantifying bone samples are discussed and the minimum numbers approach criti... more ABSTRACT Methods of quantifying bone samples are discussed and the minimum numbers approach criticized. A technique based upon number estimation of game populations is put forward, and some of the practical difficulties of this method are examined. Consideration is given to the underlying statistical assumptions involved in quantified analysis of bone samples, and a method of calculating confidence limits for death population numbers proposed.

Research paper thumbnail of Echocardiography in cardiovascular drug assessment

Heart, 1979

The validity of using echocardiography to measure the effects of cardiovascular drugs on the hear... more The validity of using echocardiography to measure the effects of cardiovascular drugs on the heart has been investigated. A standardised method of measuring left ventricular diameters is described and used to measure variability and therefore reproducibility in 20 subjects. Immediate variability was measured in 10 normal subjects. In 5 of these subjects variability was measured every few minutes, hourly, and weekly during control periods of drug studies and also after an interval of 1 year. Estimates were made of the minimum significant change in heart size which could be defined under these circumstances. Reproducibility decreased with increasing time interval between studies but overall was very good (coefficient of variation in diameters from 1 to 8%). Even with a time interval of 1 year the individual absolute difference in the mean ofdiameters was never greater than 0-3 cm. Reproducibility was similar in small groups of patients with hypertension or ischaemic heart disease (without dyskinesia).

Research paper thumbnail of Left ventricular function during pregnancy

Research paper thumbnail of Paleobiological Investigations. Research Design, Methods and Data Analysis

American Journal of Archaeology, 1986

Research paper thumbnail of An ancient HLA type from a Palaeolithic skeleton from Theopetra Cave, Greece

The site of Theopetra Cave is exceptional, having yielded human remains from the Palaeolithic, Me... more The site of Theopetra Cave is exceptional, having yielded human remains from the Palaeolithic, Mesolithic and Neolithic periods. It offers a unique opportunity to apply ancient DNA analysis to skeletal material from well controlled archaeological contexts. Following promising preliminary results from the Palaeolithic skeleton a detailed analysis of the highly variable HLA DR, DQ region was pursued, yielding the same DNA type in duplicate analyses derived from independent bone extracts. Limited contamination with intrusive DNA was experienced in the study, suggesting that the results from the Palaeolithic skeleton are genuine. The DNA types detected are typical of both the postulated "Mesolithic hunter-gatherers" and "Near Eastern farmers" in the wave of advance model of Ammerman and Cavalli-Sforza. The implications of these findings from the Palaeolithic skeleton from Theopetra Cave are discussed.

Research paper thumbnail of An anthropometric approach to forensic facial comparison

Research paper thumbnail of Statistical tests for clustering of second phases in composite materials

Philosophical Magazine A, 1995

A statistical comparison is made of various tests for the randomness or otherwise of second-phase... more A statistical comparison is made of various tests for the randomness or otherwise of second-phase particles in composite materials. Quadrat, nearest-neighbour, Ripley's K function and Dirichlet tessellation-based tests are compared. It is found that a test based on Ripley's K function performs well in detecting both clustered and regular alternatives to randomness. Additionally these tests have the benefit of providing

Research paper thumbnail of A Large Database Sample of 3D Facial Images and Measurements

Computer-Aided Forensic Facial Comparison, 2010

Tools for forensic facial comparison will inevitably rely on estimations of face shape frequency ... more Tools for forensic facial comparison will inevitably rely on estimations of face shape frequency in the general population. In order to provide sample from which estimates of shape frequency can be derived, a database of facial images and measurements is essential. A database additionally allows questions of representativeness-such as by age, sex and ancestry-to be addressed and, finally, it permits patterns of variation within the database itself to be understood with empirical confidence. This Chapter describes the collection of a large database of facial images and anthropometric landmark datasets in 3D. The investigation described in Chapter 3 served, effectively, as a pilot study in which an optimal selection of anthropometric landmarks was identified that could be used to collect measurements from a large quantity of facial images. The pilot investigation also allowed methods of training and quality assurance for operators to be developed.

Research paper thumbnail of Multivariate Outliers

Encyclopedia of Statistics in Behavioral Science, 2005

Research paper thumbnail of Cluster analysis

Cognitive Foundations of Language Structure and Use, 2014

Research paper thumbnail of Generation of Values for Missing

Computer-Aided Forensic Facial Comparison, 2010

Research paper thumbnail of Statistical Modelling and Computing

Much of the course will be focused around the computing system R which provides various statistic... more Much of the course will be focused around the computing system R which provides various statistical facilities including high quality graphics. It is an open source system and is available free. It is 'not unlike' the expensive commercial package S-PLUS, the prime difference is that R is command-line driven without the standard menus and dialog boxes in S-PLUS. Otherwise, most code written for the two systems is interchangeable.

Research paper thumbnail of From sand grains to tomatoes: applications of size distributions

Research paper thumbnail of Hilda M. Davies, 1914-2008

Journal of the Royal Statistical Society Series A (Statistics in Society)

Research paper thumbnail of Morris Walker, 1921-2010

Journal of the Royal Statistical Society Series A (Statistics in Society)

Research paper thumbnail of Multivariate Outliers

Wiley StatsRef: Statistics Reference Online, 2014

Research paper thumbnail of INFLUENCE FUNCTIONS IN FUNCTIONAL MEASUREMENT ERROR MODELS WITH REPLICATED DATA

Statistics, 2003

ABSTRACT We consider the construction and properties of influence functions in the context of fun... more ABSTRACT We consider the construction and properties of influence functions in the context of functional measurement error models with replicated data. In these models estimates of the parameters can be affected both by the individual observations and the means of replicated observations. We show that influence function of the means of replicates on the estimate of regression coefficients can be only derived under the assumption that the variances of the errors are known, while one for the individual observations can be only derived simultaneously with their influence function on the estimators of the variances of the errors.

Research paper thumbnail of Archaeostatistics: Old Statistics in Ancient Contexts

Research paper thumbnail of The Identification of Multiple Outliers: Comment

Journal of the American Statistical Association, 1993

Research paper thumbnail of Considerations of minimum numbers: a response to Horton

Journal of Archaeological Science, 1985

ABSTRACT This paper discusses a recent evaluation of bone assemblage quantification methods based... more ABSTRACT This paper discusses a recent evaluation of bone assemblage quantification methods based in large part upon a critique of our own published work. We aim to show that the critique reveals a misunderstanding of our proposals and of the aims of quantification techniques in this field.

Research paper thumbnail of Number estimation in vertebrate samples

Journal of Archaeological Science, 1982

ABSTRACT Methods of quantifying bone samples are discussed and the minimum numbers approach criti... more ABSTRACT Methods of quantifying bone samples are discussed and the minimum numbers approach criticized. A technique based upon number estimation of game populations is put forward, and some of the practical difficulties of this method are examined. Consideration is given to the underlying statistical assumptions involved in quantified analysis of bone samples, and a method of calculating confidence limits for death population numbers proposed.

Research paper thumbnail of Echocardiography in cardiovascular drug assessment

Heart, 1979

The validity of using echocardiography to measure the effects of cardiovascular drugs on the hear... more The validity of using echocardiography to measure the effects of cardiovascular drugs on the heart has been investigated. A standardised method of measuring left ventricular diameters is described and used to measure variability and therefore reproducibility in 20 subjects. Immediate variability was measured in 10 normal subjects. In 5 of these subjects variability was measured every few minutes, hourly, and weekly during control periods of drug studies and also after an interval of 1 year. Estimates were made of the minimum significant change in heart size which could be defined under these circumstances. Reproducibility decreased with increasing time interval between studies but overall was very good (coefficient of variation in diameters from 1 to 8%). Even with a time interval of 1 year the individual absolute difference in the mean ofdiameters was never greater than 0-3 cm. Reproducibility was similar in small groups of patients with hypertension or ischaemic heart disease (without dyskinesia).

Research paper thumbnail of Left ventricular function during pregnancy

Research paper thumbnail of Paleobiological Investigations. Research Design, Methods and Data Analysis

American Journal of Archaeology, 1986

Research paper thumbnail of An ancient HLA type from a Palaeolithic skeleton from Theopetra Cave, Greece

The site of Theopetra Cave is exceptional, having yielded human remains from the Palaeolithic, Me... more The site of Theopetra Cave is exceptional, having yielded human remains from the Palaeolithic, Mesolithic and Neolithic periods. It offers a unique opportunity to apply ancient DNA analysis to skeletal material from well controlled archaeological contexts. Following promising preliminary results from the Palaeolithic skeleton a detailed analysis of the highly variable HLA DR, DQ region was pursued, yielding the same DNA type in duplicate analyses derived from independent bone extracts. Limited contamination with intrusive DNA was experienced in the study, suggesting that the results from the Palaeolithic skeleton are genuine. The DNA types detected are typical of both the postulated "Mesolithic hunter-gatherers" and "Near Eastern farmers" in the wave of advance model of Ammerman and Cavalli-Sforza. The implications of these findings from the Palaeolithic skeleton from Theopetra Cave are discussed.

Research paper thumbnail of An anthropometric approach to forensic facial comparison

Research paper thumbnail of Statistical tests for clustering of second phases in composite materials

Philosophical Magazine A, 1995

A statistical comparison is made of various tests for the randomness or otherwise of second-phase... more A statistical comparison is made of various tests for the randomness or otherwise of second-phase particles in composite materials. Quadrat, nearest-neighbour, Ripley's K function and Dirichlet tessellation-based tests are compared. It is found that a test based on Ripley's K function performs well in detecting both clustered and regular alternatives to randomness. Additionally these tests have the benefit of providing

Research paper thumbnail of A Large Database Sample of 3D Facial Images and Measurements

Computer-Aided Forensic Facial Comparison, 2010

Tools for forensic facial comparison will inevitably rely on estimations of face shape frequency ... more Tools for forensic facial comparison will inevitably rely on estimations of face shape frequency in the general population. In order to provide sample from which estimates of shape frequency can be derived, a database of facial images and measurements is essential. A database additionally allows questions of representativeness-such as by age, sex and ancestry-to be addressed and, finally, it permits patterns of variation within the database itself to be understood with empirical confidence. This Chapter describes the collection of a large database of facial images and anthropometric landmark datasets in 3D. The investigation described in Chapter 3 served, effectively, as a pilot study in which an optimal selection of anthropometric landmarks was identified that could be used to collect measurements from a large quantity of facial images. The pilot investigation also allowed methods of training and quality assurance for operators to be developed.

Research paper thumbnail of An anthropometric approach to forensic facial comparison

Australian and New Zealand Forensic Science Society 18th International Symposium on the Forensic Sciences, 101-2. , 2006