title: Comparing cross-sectional and longitudinal tracking to establish percentile data and assess performance progression in swimmers

authors: Born, Dennis‑Peter

subjects: Science & Technology

abstract: To provide percentile curves for short-course swimming events, including 5 swimming strokes, 6 race distances, and both sexes, as well as to compare diferences in race times between cross-sectional analysis and longitudinal tracking, a total of 31,645,621 race times of male and female swimmers were analyzed. Two percentile datasets were established from individual swimmers’ annual best times and a two-way analysis of variance (ANOVA) was used to determine diferences between cross-sectional analysis and longitudinal tracking. A software-based percentile calculator was provided to extract the exact percentile for a given race time. Longitudinal tracking reduced the number of annual best times that were included in the percentiles by 98.35% to 262,071 and showed faster mean race times (P< 0.05) compared to the cross-sectional analysis. This diference was found in the lower percentiles (1st to 20th) across all age categories (P< 0.05); however, in the upper percentiles (80th to 99th), longitudinal tracking showed faster race times during early and late junior age only (P< 0.05), after which race times approximated cross-sectional tracking. The percentile calculator provides quick and easy data access to facilitate practical application of percentiles in training or competition. Longitudinal tracking that accounts for drop-out may predict performance progression towards elite age, particularly for high-performance swimmers.

text: Comparing cross-sectional and longitudinal tracking to establish percentile data and assess performance progression in swimmers To provide percentile curves for short-course swimming events, including 5 swimming strokes, 6 race distances, and both sexes, as well as to compare diferences in race times between cross-sectional analysis and longitudinal tracking, a total of 31,645,621 race times of male and female swimmers were analyzed. Two percentile datasets were established from individual swimmers’ annual best times and a two-way analysis of variance (ANOVA) was used to determine diferences between cross-sectional analysis and longitudinal tracking. A software-based percentile calculator was provided to extract the exact percentile for a given race time. Longitudinal tracking reduced the number of annual best times that were included in the percentiles by 98.35% to 262,071 and showed faster mean race times (P< 0.05) compared to the cross-sectional analysis. This diference was found in the lower percentiles (1st to 20th) across all age categories (P< 0.05); however, in the upper percentiles (80th to 99th), longitudinal tracking showed faster race times during early and late junior age only (P< 0.05), after which race times approximated cross-sectional tracking. The percentile calculator provides quick and easy data access to facilitate practical application of percentiles in training or competition. Longitudinal tracking that accounts for drop-out may predict performance progression towards elite age, particularly for high-performance swimmers.

year: 2022

title: Communicating the value of marine conservation using an ecosystem service matrix approach

authors: Geange, Shane

subjects: Science & Technology

abstract: Matrix approaches are useful for linking ecosystem services to habitats that underpin their delivery. Matrix applications in marine ecosystem services research have been primarily qualitative, focusing on 'habitat presence' without including other attributes that effect service potential. We developed an evidence-based matrix approach of Ecosystem Service Potential (ESP) for New Zealand benthic marine habitats, and used two marine reserves to demonstrate that integrating information on the spatial extent and quality of habitats improved ESP evaluation. The two case studies identified substantial spatio-temporal variability in ESP: within one reserve, specific ESP showed an approximately 1.5-fold increase in the 29 years following protection. A comparison of two reserves found that the spatial extent of habitats contributing to the medicinal resources and waste-water treatment were 5 and 53 times greater respectively in one relative to the other. Integrating habitat area and quality with the ESP matrix improves on previous marine matrix-based approaches, providing a better indication of service potential. The matrix approach helps to communicate the non-market value of supporting and regulating services and can be used by resource managers to identify and track the potential for benefits derived from benthic marine habitats within existing, or new, marine protected areas.

text: Communicating the value of marine conservation using an ecosystem service matrix approach Matrix approaches are useful for linking ecosystem services to habitats that underpin their delivery. Matrix applications in marine ecosystem services research have been primarily qualitative, focusing on 'habitat presence' without including other attributes that effect service potential. We developed an evidence-based matrix approach of Ecosystem Service Potential (ESP) for New Zealand benthic marine habitats, and used two marine reserves to demonstrate that integrating information on the spatial extent and quality of habitats improved ESP evaluation. The two case studies identified substantial spatio-temporal variability in ESP: within one reserve, specific ESP showed an approximately 1.5-fold increase in the 29 years following protection. A comparison of two reserves found that the spatial extent of habitats contributing to the medicinal resources and waste-water treatment were 5 and 53 times greater respectively in one relative to the other. Integrating habitat area and quality with the ESP matrix improves on previous marine matrix-based approaches, providing a better indication of service potential. The matrix approach helps to communicate the non-market value of supporting and regulating services and can be used by resource managers to identify and track the potential for benefits derived from benthic marine habitats within existing, or new, marine protected areas.

year: 2019

title: Māori and the [potential] demographic dividend

authors: Jackson, Natalie

subjects: demography

abstract: This paper outlines a recently articulated concept in the demographic literature known as the ‘demographic dividend’, and connects it with key features of Māori and non- Māori demography. The dividend arises – or has the potential to arise - as each population passes through a particular point in its demographic transition. During these years, the maximum proportion of the population moves into the key working and income-earning age groups, and the minimum (comprised of youth and the elderly) is notionally dependent. With proactive and timely investment in the youthful base of the population, there is potential to convert the demographic dividend into two economic windfalls, the first arising as fertility decline causes youthful dependency to fall and the last large waves of young adults flood into the working age population, the second as the latter age and move on into the higher income earning age groups. However the window of opportunity to invest in the first dividend is fleeting, while failure to invest in that stage seriously compromises the second. This paper shows that for the Māori population, despite its relative youth, the first opportunity is already coming to an end and with it the potential gains of the second. But it also argues that there is a third window of opportunity which holds particular promise for Māori. This period will also be fleeting, but is arising in both absolute and relative terms as the relatively youthful Māori population co-exists alongside its structurally older counterpart, and together (with other New Zealanders) comprise an ‘economic dividend system’ that produces the potential for a ‘collateral dividend’.

text: Māori and the [potential] demographic dividend This paper outlines a recently articulated concept in the demographic literature known as the ‘demographic dividend’, and connects it with key features of Māori and non- Māori demography. The dividend arises – or has the potential to arise - as each population passes through a particular point in its demographic transition. During these years, the maximum proportion of the population moves into the key working and income-earning age groups, and the minimum (comprised of youth and the elderly) is notionally dependent. With proactive and timely investment in the youthful base of the population, there is potential to convert the demographic dividend into two economic windfalls, the first arising as fertility decline causes youthful dependency to fall and the last large waves of young adults flood into the working age population, the second as the latter age and move on into the higher income earning age groups. However the window of opportunity to invest in the first dividend is fleeting, while failure to invest in that stage seriously compromises the second. This paper shows that for the Māori population, despite its relative youth, the first opportunity is already coming to an end and with it the potential gains of the second. But it also argues that there is a third window of opportunity which holds particular promise for Māori. This period will also be fleeting, but is arising in both absolute and relative terms as the relatively youthful Māori population co-exists alongside its structurally older counterpart, and together (with other New Zealanders) comprise an ‘economic dividend system’ that produces the potential for a ‘collateral dividend’.

year: 2011-06