Australian and New Zealand Journal of Statistics This is an RSS file. You can use it to subscribe to this data in your favourite RSS reader or to display this data on your own website or blog.

Issue Information
(Source: Australian and New Zealand Journal of Statistics)
Source: Australian and New Zealand Journal of Statistics - August 2, 2022 Category: Statistics Tags: Issue Information Source Type: research

Bayesian hierarchical mixture models for detecting non ‐normal clusters applied to noisy genomic and environmental datasets
SummaryClustering to find subgroups with common features is often a necessary first step in the statistical modelling and analysis of large and complex datasets. Although follow-up analyses often make use of complex statistical models that are appropriate for the specific application, most popular clustering approaches are either nonparametric, or based on Gaussian mixture models and their variants, often for reasons of computational efficiency. Certain characteristics in the data, such as the presence of outliers, or non-ellipsoidal cluster shapes, that are common in modern scientific datasets, often lead these methods to...
Source: Australian and New Zealand Journal of Statistics - August 1, 2022 Category: Statistics Authors: Huizi Zhang, Ben Swallow, Mayetri Gupta Tags: Original Article Source Type: research

Bayesian non ‐parametric spatial prior for traffic crash risk mapping: A case study of Victoria, Australia
SummaryWe develop a Bayesian non-parametric (BNP) model coupled with Markov random fields (MRFs) for risk mapping, to infer homogeneous spatial regions in terms of risks. In contrast to most existing methods, the proposed approach does not require an arbitrary commitment to a specified number of risk classes and determines their risk levels automatically. We consider settings in which the relevant information are counts and propose a so-called BNP hidden MRF (BNP-HMRF) model that is able to handle such data. The model inference is carried out using a variational Bayes expectation –maximisation algorithm and the approach ...
Source: Australian and New Zealand Journal of Statistics - July 11, 2022 Category: Statistics Authors: J. ‐B. Durand, F. Forbes, C.D. Phan, L. Truong, H.D. Nguyen, F. Dama Tags: Special Issue Source Type: research

Visualising the pattern of long ‐term genotype performance by leveraging a genomic prediction model
AbstractHistorical data from plant breeding programs provide valuable resources to study the response of genotypes to the changing environment (i.e. genotype-by-environment interaction). Such data have been used to evaluate the pattern of genotype performance across regions or locations, but its use to evaluate the long-term pattern of genotype performance across environments (i.e. locations-by-years) has been hampered by the lack of common genotypes across years. This lack of common genotypes is due to the structure of the breeding program, especially for annual crops, where only a proportion of selected genotypes are tes...
Source: Australian and New Zealand Journal of Statistics - May 4, 2022 Category: Statistics Authors: Vivi N. Arief, Ian H. DeLacy, Thomas Payne, Kaye E. Basford Tags: Original Article Source Type: research

Erratum
(Source: Australian and New Zealand Journal of Statistics)
Source: Australian and New Zealand Journal of Statistics - April 28, 2022 Category: Statistics Tags: Erratum Source Type: research

Issue Information
(Source: Australian and New Zealand Journal of Statistics)
Source: Australian and New Zealand Journal of Statistics - April 28, 2022 Category: Statistics Tags: Issue Information Source Type: research

Functional dimension reduction based on fuzzy partition and transformation
SummaryFunctional sliced inverse regression (FSIR) is the among most popular methods for the functional dimension reduction. However, FSIR has two evident shortcomings. On the one hand, the number of samples in each slice must not be too small and selecting a suitableS is difficult, particularly for data with small sample size, whereS indicates the number of slices. On the other hand, FSIR and its related methods are well-known for their poor performance when the link function is an even (or symmetric) dependency. To solve these two problems, we propose three new types of estimation methods. First, we propose the functiona...
Source: Australian and New Zealand Journal of Statistics - April 26, 2022 Category: Statistics Authors: Beiting Liang, Taoxuan Gao, Defa Bai, Guochang Wang Tags: Original Article Source Type: research

Smooth tests of goodness of fit for the distributional assumption of regression models
We present several examples to illustrate the wide applicability of our method. A small simulation study demonstrates that our tests have power to detect important deviations from the hypothesised model. (Source: Australian and New Zealand Journal of Statistics)
Source: Australian and New Zealand Journal of Statistics - April 19, 2022 Category: Statistics Authors: J. C. W. Rayner, Paul Rippon, Thomas Suesse, Olivier Thas Tags: Original Article Source Type: research

MPS: An R package for modelling shifted families of distributions
SummaryGeneralised statistical distributions have been widely used over the last decades for modelling phenomena in different fields. The generalisations have been made to produce distributions with more flexibility and lead to more accurate modelling in practice. Statistical analysis of the generalised distributions requires new statistical packages. TheNewdistns package due to Nadarajah and Rocha providesR routines with functionality to compute probability density function (PDF), cumulative distribution function (CDF), quantile function, random numbers and parameter estimates of 19 families of distributions with applicat...
Source: Australian and New Zealand Journal of Statistics - April 15, 2022 Category: Statistics Authors: Mahdi Teimouri, Saralees Nadarajah Tags: Original Article Source Type: research

Modal clustering on PPGMMGA projection subspace
SummaryPPGMMGA is a projection pursuit (PP) algorithm aimed at detecting and visualising clustering structures in multivariate data. The algorithm uses the negentropy as PP index obtained by fitting Gaussian mixture models (GMMs) for density estimation and, then, exploits genetic algorithms (GAs) for its optimisation. Since the PPGMMGA algorithm is a dimension reduction technique specifically introduced for visualisation purposes, cluster memberships are not explicitly provided. In this paper a modal clustering approach is proposed for estimating clusters of projected data points. In particular, a modal EM algorithm is emp...
Source: Australian and New Zealand Journal of Statistics - April 14, 2022 Category: Statistics Authors: Luca Scrucca Tags: Original Article Source Type: research

Issue Information
(Source: Australian and New Zealand Journal of Statistics)
Source: Australian and New Zealand Journal of Statistics - March 11, 2022 Category: Statistics Tags: Issue Information Source Type: research

Fast and efficient algorithms for sparse semiparametric bifunctional regression
SummaryA new sparse semiparametric model is proposed, which incorporates the influence of two functional random variables in a scalar response in a flexible and interpretable manner. One of the functional covariates is included through a single-index structure, while the other is included linearly through the high-dimensional vector formed by its discretised observations. For this model, two new algorithms are presented for selecting relevant variables in the linear part and estimating the model. Both procedures utilise the functional origin of linear covariates. Finite sample experiments demonstrated the scope of applicat...
Source: Australian and New Zealand Journal of Statistics - March 9, 2022 Category: Statistics Authors: Silvia Novo, Philippe Vieu, Germ án Aneiros Tags: Original Article Source Type: research

Bessel regression and bbreg package to analyse bounded data
SummaryBeta regression has been extensively used by statisticians and practitioners to model bounded continuous data without a strong competitor having the same main features. A class of normalised inverse-Gaussian (N-IG) process was introduced in the literature and has been explored in the Bayesian context as a powerful alternative to the Dirichlet process. Until this moment, no attention has been paid to the univariate N-IG distribution in the classical inference. In this paper, we propose the bessel regression based on the univariate N-IG distribution, which is an alternative to the beta model. The estimation of the par...
Source: Australian and New Zealand Journal of Statistics - February 13, 2022 Category: Statistics Authors: Wagner Barreto ‐Souza, Vinícius D. Mayrink, Alexandre B. Simas Tags: Original Article Source Type: research

Spying on the prior of the number of data clusters and the partition distribution in Bayesian cluster analysis
SummaryCluster analysis aims at partitioning data into groups or clusters. In applications, it is common to deal with problems where the number of clusters is unknown. Bayesian mixture models employed in such applications usually specify a flexible prior that takes into account the uncertainty with respect to the number of clusters. However, a major empirical challenge involving the use of these models is in the characterisation of the induced prior on the partitions. This work introduces an approach to compute descriptive statistics of the prior on the partitions for three selected Bayesian mixture models developed in the...
Source: Australian and New Zealand Journal of Statistics - February 11, 2022 Category: Statistics Authors: Jan Greve, Bettina Gr ün, Gertraud Malsiner‐Walli, Sylvia Frühwirth‐Schnatter Tags: Invited Review Source Type: research

Modelling students ’ career indicators via mixtures of parsimonious matrix‐normal distributions
SummaryThe evaluation of the teaching efficiency, under different points of view, is an important aspect for the university system because it helps managers to improve more and more the quality of the education and helps students to achieve strong professional skills. In this framework, students ’ careers as well as teachers’ qualification and quantity adequacy indicators are analysed based on data sets provided by the Italian National Agency for the Evaluation of Universities and Research Institutes (ANVUR) according to a mixture model approach. In particular, parsimonious mixtures of matrix-normal distributions are u...
Source: Australian and New Zealand Journal of Statistics - February 10, 2022 Category: Statistics Authors: Salvatore D. Tomarchio, Salvatore Ingrassia, Volodymyr Melnykov Tags: Geoff McLachlan Festschrift Source Type: research