title: Mobile phone use while driving after a new national law in New Zealand

authors: Starkey, Nicola J.

abstract: Mobile phone use while driving leads to impairments in driver performance including slowed reaction times, poor lane keeping and reduced hazard detection. To increase public safety, in 2009 the New Zealand (NZ) Government introduced a ban on the use of hand-held phones while driving. The aim of the current to study was to identify the post-law prevalence of phone use while driving. Observers recorded drivers’ mobile phone use at or near traffic lights and in moving traffic at three locations (Central Business District, and two suburbs of contrasting area-based deprivation) in Wellington, NZ. A total of 8335 cars at traffic lights and 9520 cars in moving traffic were systematically observed. The use of mobile phones by drivers at these locations were 1.87% (95%CI: 1.60-2.18) and 1.34% (95%CI: 1.13-1.59) respectively. Younger drivers (<25 years) were significantly more likely to use their phones compared to older drivers (e.g., in moving traffic, risk ratio = 2.91, 95%CI=2.00–4.22). Overall, it was much more common for drivers to use their phones in a “non-ear position” (77.8%) than next to their ear, and this was also significantly higher among younger drivers. These data suggest that there has been a decline in phone use when driving as compared to rates of 3.9% reported in a pre-law study (in Auckland). Although these findings are encouraging, phone use while driving is still relatively high. Options such as mass media campaigns, enhanced enforcement, and higher penalties for breaking the law may need to be considered to further address this issue.

text: Mobile phone use while driving after a new national law in New Zealand Mobile phone use while driving leads to impairments in driver performance including slowed reaction times, poor lane keeping and reduced hazard detection. To increase public safety, in 2009 the New Zealand (NZ) Government introduced a ban on the use of hand-held phones while driving. The aim of the current to study was to identify the post-law prevalence of phone use while driving. Observers recorded drivers’ mobile phone use at or near traffic lights and in moving traffic at three locations (Central Business District, and two suburbs of contrasting area-based deprivation) in Wellington, NZ. A total of 8335 cars at traffic lights and 9520 cars in moving traffic were systematically observed. The use of mobile phones by drivers at these locations were 1.87% (95%CI: 1.60-2.18) and 1.34% (95%CI: 1.13-1.59) respectively. Younger drivers (<25 years) were significantly more likely to use their phones compared to older drivers (e.g., in moving traffic, risk ratio = 2.91, 95%CI=2.00–4.22). Overall, it was much more common for drivers to use their phones in a “non-ear position” (77.8%) than next to their ear, and this was also significantly higher among younger drivers. These data suggest that there has been a decline in phone use when driving as compared to rates of 3.9% reported in a pre-law study (in Auckland). Although these findings are encouraging, phone use while driving is still relatively high. Options such as mass media campaigns, enhanced enforcement, and higher penalties for breaking the law may need to be considered to further address this issue.

year: 2013-08-28

title: Correlating tephras and cryptotephras using glass compositional analyses and numerical and statistical methods: review and evaluation

authors: Lowe, David J.

subjects: Tephra

abstract: We define tephras and cryptotephras and their components (mainly ash-sized particles of glass ± crystals in distal deposits) and summarize the basis of tephrochronology as a chronostratigraphic correlational and dating tool for palaeoenvironmental, geological, and archaeological research. We then document and appraise recent advances in analytical methods used to determine the major, minor, and trace elements of individual glass shards from tephra or cryptotephra deposits to aid their correlation and application. Protocols developed recently for the electron probe microanalysis of major elements in individual glass shards help to improve data quality and standardize reporting procedures. A narrow electron beam (diameter ~3-5 μm) can now be used to analyze smaller glass shards than previously attainable. Reliable analyses of ‘microshards’ (defined here as glass shards <32 µm in diameter) using narrow beams are useful for fine-grained samples from distal or ultra-distal geographic locations, and for vesicular or microlite-rich glass shards or small melt inclusions. Caveats apply, however, in the microprobe analysis of very small microshards (<=~5 µm in diameter), where particle geometry becomes important, and of microlite-rich glass shards where the potential problem of secondary fluorescence across phase boundaries needs to be recognised. Trace element analyses of individual glass shards using laser ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS), with crater diameters of 20 μm and 10 μm, are now effectively routine, giving detection limits well below 1 ppm. Smaller ablation craters (<10 μm) can be subject to significant element fractionation during analysis, but the systematic relationship of such fractionation with glass composition suggests that analyses for some elements at these resolutions may be quantifiable. In undertaking analyses, either by microprobe or LA-ICP-MS, reference material data acquired using the same procedure, and preferably from the same analytical session, should be presented alongside new analytical data. 
In part 2 of the review, we describe, critically assess, and recommend ways in which tephras or cryptotephras can be correlated (in conjunction with other information) using numerical or statistical analyses of compositional data. Statistical methods provide a less subjective means of dealing with analytical data pertaining to tephra components (usually glass or crystals/phenocrysts) than heuristic alternatives. They enable a better understanding of relationships among the data from multiple viewpoints to be developed and help quantify the degree of uncertainty in establishing correlations. In common with other scientific hypothesis testing, it is easier to infer using such analysis that two or more tephras are different rather than the same. Adding stratigraphic, chronological, spatial, or palaeoenvironmental data (i.e. multiple criteria) is usually necessary and allows for more robust correlations to be made. A two-stage approach is useful, the first focussed on differences in the mean composition of samples, or their range, which can be visualised graphically via scatterplot matrices or bivariate plots coupled with the use of statistical tools such as distance measures, similarity coefficients, hierarchical cluster analysis (informed by distance measures or similarity or cophenetic coefficients), and principal components analysis (PCA). Some statistical methods (cluster analysis, discriminant analysis) are referred to as ‘machine learning’ in the computing literature. The second stage examines sample variance and the degree of compositional similarity so that sample equivalence or otherwise can be established on a statistical basis. This stage may involve discriminant function analysis (DFA), support vector machines (SVMs), canonical variates analysis (CVA), and ANOVA or MANOVA (or its two-sample special case, the Hotelling two-sample T² test). Randomization tests can be used where distributional assumptions such as multivariate normality underlying parametric tests are doubtful.
Compositional data may be transformed and scaled before being subjected to multivariate statistical procedures including calculation of distance matrices, hierarchical cluster analysis, and PCA. Such transformations may make the assumption of multivariate normality more appropriate. A sequential procedure using Mahalanobis distance and the Hotelling two-sample T² test is illustrated using glass major element data from trachytic to phonolitic Kenyan tephras. All these methods require a broad range of high-quality compositional data which can be used to compare ‘unknowns’ with reference (training) sets that are sufficiently complete to account for all possible correlatives, including tephras with heterogeneous glasses that contain multiple compositional groups. Currently, incomplete databases are tending to limit correlation efficacy. The development of an open, online global database to facilitate progress towards integrated, high-quality tephrostratigraphic frameworks for different regions is encouraged.

text: Correlating tephras and cryptotephras using glass compositional analyses and numerical and statistical methods: review and evaluation We define tephras and cryptotephras and their components (mainly ash-sized particles of glass ± crystals in distal deposits) and summarize the basis of tephrochronology as a chronostratigraphic correlational and dating tool for palaeoenvironmental, geological, and archaeological research. We then document and appraise recent advances in analytical methods used to determine the major, minor, and trace elements of individual glass shards from tephra or cryptotephra deposits to aid their correlation and application. Protocols developed recently for the electron probe microanalysis of major elements in individual glass shards help to improve data quality and standardize reporting procedures. A narrow electron beam (diameter ~3-5 μm) can now be used to analyze smaller glass shards than previously attainable. Reliable analyses of ‘microshards’ (defined here as glass shards <32 µm in diameter) using narrow beams are useful for fine-grained samples from distal or ultra-distal geographic locations, and for vesicular or microlite-rich glass shards or small melt inclusions. Caveats apply, however, in the microprobe analysis of very small microshards (<=~5 µm in diameter), where particle geometry becomes important, and of microlite-rich glass shards where the potential problem of secondary fluorescence across phase boundaries needs to be recognised. Trace element analyses of individual glass shards using laser ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS), with crater diameters of 20 μm and 10 μm, are now effectively routine, giving detection limits well below 1 ppm. Smaller ablation craters (<10 μm) can be subject to significant element fractionation during analysis, but the systematic relationship of such fractionation with glass composition suggests that analyses for some elements at these resolutions may be quantifiable. In undertaking analyses, either by microprobe or LA-ICP-MS, reference material data acquired using the same procedure, and preferably from the same analytical session, should be presented alongside new analytical data. 
In part 2 of the review, we describe, critically assess, and recommend ways in which tephras or cryptotephras can be correlated (in conjunction with other information) using numerical or statistical analyses of compositional data. Statistical methods provide a less subjective means of dealing with analytical data pertaining to tephra components (usually glass or crystals/phenocrysts) than heuristic alternatives. They enable a better understanding of relationships among the data from multiple viewpoints to be developed and help quantify the degree of uncertainty in establishing correlations. In common with other scientific hypothesis testing, it is easier to infer using such analysis that two or more tephras are different rather than the same. Adding stratigraphic, chronological, spatial, or palaeoenvironmental data (i.e. multiple criteria) is usually necessary and allows for more robust correlations to be made. A two-stage approach is useful, the first focussed on differences in the mean composition of samples, or their range, which can be visualised graphically via scatterplot matrices or bivariate plots coupled with the use of statistical tools such as distance measures, similarity coefficients, hierarchical cluster analysis (informed by distance measures or similarity or cophenetic coefficients), and principal components analysis (PCA). Some statistical methods (cluster analysis, discriminant analysis) are referred to as ‘machine learning’ in the computing literature. The second stage examines sample variance and the degree of compositional similarity so that sample equivalence or otherwise can be established on a statistical basis. This stage may involve discriminant function analysis (DFA), support vector machines (SVMs), canonical variates analysis (CVA), and ANOVA or MANOVA (or its two-sample special case, the Hotelling two-sample T² test). Randomization tests can be used where distributional assumptions such as multivariate normality underlying parametric tests are doubtful.
Compositional data may be transformed and scaled before being subjected to multivariate statistical procedures including calculation of distance matrices, hierarchical cluster analysis, and PCA. Such transformations may make the assumption of multivariate normality more appropriate. A sequential procedure using Mahalanobis distance and the Hotelling two-sample T² test is illustrated using glass major element data from trachytic to phonolitic Kenyan tephras. All these methods require a broad range of high-quality compositional data which can be used to compare ‘unknowns’ with reference (training) sets that are sufficiently complete to account for all possible correlatives, including tephras with heterogeneous glasses that contain multiple compositional groups. Currently, incomplete databases are tending to limit correlation efficacy. The development of an open, online global database to facilitate progress towards integrated, high-quality tephrostratigraphic frameworks for different regions is encouraged.

year: 2017

title: Governance and legitimacy: Indigenous development in Aotearoa

authors: Dodd, Materoa

subjects: Māori governance

abstract: Within the indigenous paradigm lies a paradox over what constitutes legitimate Māori authority: Iwi structures are legitimated and recognised by the state, and traditional forms (for example, Hapū and Māori women), have had their authority diminished. Iwi authorities are colonial constructs that diminish the rights of Hapū and Māori women. The manner in which such constructs have come about generally has not involved tribewide debate over important issues in which Hapū and Māori women have an interest. For their legitimacy, emergent self-governing structures will need to be grounded in principles that ensure legitimate representation of Māori people and not socially constructed hybrids of a colonial past. Structures need to recognise Hapū and Māori women in the formulation, anything less than this will trigger a legitimation crisis.

text: Governance and legitimacy: Indigenous development in Aotearoa Within the indigenous paradigm lies a paradox over what constitutes legitimate Māori authority: Iwi structures are legitimated and recognised by the state, and traditional forms (for example, Hapū and Māori women), have had their authority diminished. Iwi authorities are colonial constructs that diminish the rights of Hapū and Māori women. The manner in which such constructs have come about generally has not involved tribewide debate over important issues in which Hapū and Māori women have an interest. For their legitimacy, emergent self-governing structures will need to be grounded in principles that ensure legitimate representation of Māori people and not socially constructed hybrids of a colonial past. Structures need to recognise Hapū and Māori women in the formulation, anything less than this will trigger a legitimation crisis.

year: 2000-10