title: Nowcasting and predicting data revisions using panel survey data

authors: Matheson, Troy D.

subjects: nowcasting

abstract: The qualitative responses that firms give to business survey questions regarding changes in their own output provide a real-time signal of official output changes. The most commonly used method to produce an aggregate quantitative indicator from business survey responses - the net balance or diffusion index - has changed little in 40 years. This paper investigates whether an improved real-time signal of official output data changes can be derived from a recently advanced method on the aggregation of survey data from panel responses. We find, in a New Zealand application, that exploiting the panel dimension to qualitative survey data gives a better in-sample signal about official data than traditional methods. Out-of-sample, it is less clear that it matters how survey data are quantified, with simpler and more parsimonious methods hard to improve. It is clear, nevertheless, that survey data, exploited in some form, help to explain revisions to official data.

text: Nowcasting and predicting data revisions using panel survey data The qualitative responses that firms give to business survey questions regarding changes in their own output provide a real-time signal of official output changes. The most commonly used method to produce an aggregate quantitative indicator from business survey responses - the net balance or diffusion index - has changed little in 40 years. This paper investigates whether an improved real-time signal of official output data changes can be derived from a recently advanced method on the aggregation of survey data from panel responses. We find, in a New Zealand application, that exploiting the panel dimension to qualitative survey data gives a better in-sample signal about official data than traditional methods. Out-of-sample, it is less clear that it matters how survey data are quantified, with simpler and more parsimonious methods hard to improve. It is clear, nevertheless, that survey data, exploited in some form, help to explain revisions to official data.

year: 2009

title: Wave dissipation by flexible vegetation

authors: Riffe, Kassi C.

subjects: wave

abstract: Dissipation of waves propagating through natural salt marsh vegetation was about half the dissipation expected for rigid vegetation. This low dissipation was predicted by a theoretical model that accounts for bending of vegetation by wave motions. A transect of 3 pulse-coherent Acoustic Doppler Current Profilers recorded water velocity and pressure (at 8 Hz) within the dense (650 stems/m²) canopy of semi-flexible single-stem vegetation (Schoenoplectus americanus). Most wave energy (56 - 81%) was dissipated within 19 m of the marsh edge. Two dissipation models, the first assuming rigid vegetation, and the second simulating wave-forced vegetation motion using the theory for bending of linearly-elastic beams, were tested. After choosing optimal drag coefficients, both models yielded a good fit to the observed dissipation (skill score = 0.95 - 0.99). However, fitted drag coefficients for the rigid model (0.58 - 0.78) were below the range (0.98 - 2.2) expected for the observed Reynolds numbers (13 - 450) and canopy densities (accounting for interactions between stem wakes), whereas drag coefficients for the flexible model (0.97 - 1.6) were nearer the expected range, indicating that prediction of wave dissipation was improved by simulating vegetation motion.

text: Wave dissipation by flexible vegetation Dissipation of waves propagating through natural salt marsh vegetation was about half the dissipation expected for rigid vegetation. This low dissipation was predicted by a theoretical model that accounts for bending of vegetation by wave motions. A transect of 3 pulse-coherent Acoustic Doppler Current Profilers recorded water velocity and pressure (at 8 Hz) within the dense (650 stems/m²) canopy of semi-flexible single-stem vegetation (Schoenoplectus americanus). Most wave energy (56 - 81%) was dissipated within 19 m of the marsh edge. Two dissipation models, the first assuming rigid vegetation, and the second simulating wave-forced vegetation motion using the theory for bending of linearly-elastic beams, were tested. After choosing optimal drag coefficients, both models yielded a good fit to the observed dissipation (skill score = 0.95 - 0.99). However, fitted drag coefficients for the rigid model (0.58 - 0.78) were below the range (0.98 - 2.2) expected for the observed Reynolds numbers (13 - 450) and canopy densities (accounting for interactions between stem wakes), whereas drag coefficients for the flexible model (0.97 - 1.6) were nearer the expected range, indicating that prediction of wave dissipation was improved by simulating vegetation motion.

year: 2011

title: Maori and psychology: Indigenous psychology in New Zealand

authors: Nikora, Linda Waimarie

subjects: Maori

abstract: Maori have their own approaches to health and well-being, which stem from a world view that values balance, continuity, unity and purpose. The world view is not typically thought of as 'psychology', yet it is a foundation for shared understandings and intelligible action among Maori. Maori behaviours, values, ways of doing things and understandings are often not visible nor valued. However, through these opening years of the twenty-first century, psychologists are slowly turning their attention to addressing this invisibility with the explicit agenda of building 'indigenous psychologies'

text: Maori and psychology: Indigenous psychology in New Zealand Maori have their own approaches to health and well-being, which stem from a world view that values balance, continuity, unity and purpose. The world view is not typically thought of as 'psychology', yet it is a foundation for shared understandings and intelligible action among Maori. Maori behaviours, values, ways of doing things and understandings are often not visible nor valued. However, through these opening years of the twenty-first century, psychologists are slowly turning their attention to addressing this invisibility with the explicit agenda of building 'indigenous psychologies'

year: 2007