Measuring Western Australian House Prices: Methods and Implications

This paper investigates models of house price measurement with a particular focus on the hybrid hedonic repeat-sales model. It examines different ways to model house price changes and outlines a method of estimating the hybrid measure. After describing the models, the paper applies Western Australian house sales data to the outlined models and draws some conclusions as to the relative attractiveness of the hybrid measure.

Two Essays on Demographic Change and the Australian Economy

Environmental efficiency, environmental regulation, the Chinese economy.

Return to wine: A comparison of the hedonic, repeat sales, and hybrid approaches

Comparisons between the return to wine and standard financial assets are complicated in that the return to wine must be estimated from infrequent sales of heterogeneous wine brands. Wine returns can be estimated using several different approaches, and here the performance of the hedonic approach, repeat sales approach, and hybrid approach are compared using 14,102 auction sale observations for Australian wine over the period 1988 to 2000. For the data set considered the results show that the hybrid approach provides the most efficient estimates, and that the repeat sales approach provides significantly higher total return estimates than the other two approaches. The portfolio diversification benefit attributed to holding wine is then shown to vary with estimation method.Return to wine, Price index, Research Methods/ Statistical Methods, C33, G12,

Efficient and Open-Source Tool for the Prediction of Thermowell Structural Response

Thermowells are widely used in the aid of the measurement of temperature in high velocity or corrosive flow in large industrial installations. They are susceptible to vortex induced vibration which can be a cause of two types of damage; fatigue failure and resonance failure. Hence it is important to understand the mechanisms that may avoid vortex induced vibration as failure of a thermowell can cause a leak in the pipe or vessel it is installed on. An industry standard for the sizing and installation of a thermowell in order to avoid failure due to vortex induced vibration, hydrostatic pressure or static bending already exists. The standard is thorough and has been amended as recently as 2016 in order to increase safety in working with thermowells. However, it has its shortcomings with some assumptions it makes and when considering unique designs. A unique design of particular interest from industry is that of a cylindrical well with helical strakes attached. This affects the boundary layer of the fluid on the thermowell.In this work, a novel tool is developed for computing the structural response of a thermowell depending on the flow environment in which it is placed in. The tool exploits one-way coupling requiring the physics of fluid flow and solid dynamics. The incompressible Navier-Stokes equations with a RANS turbulence model and a structural modal superposition method are used to solve for the fluid and the solid. An experimental setup was also proposed with the purpose of benchmarking the numerical approach, however, experimental testing was not pursued.The numerical model showed a significant reduction in time dynamic oscillatory force being applied to the thermowell when helical strakes are introduced but an increase in steady state force. Therefore, with the presence of helical strakes, the dynamics stress levels that the thermowell experiences is reduced making the thermowell less susceptible to failure

Soft Bootstrap and Supersymmetry

The soft bootstrap is an on-shell method to constrain the landscape of effective field theories (EFTs) of massless particles via the consistency of the low-energy S-matrix. Given assumptions on the on-shell data (particle spectra, linear symmetries, and low-energy theorems), the soft bootstrap is an efficient algorithm for determining the possible consistency of an EFT with those properties. The implementation of the soft bootstrap uses the recently discovered method of soft subtracted recursion. We derive a precise criterion for the validity of these recursion relations and show that they fail exactly when the assumed symmetries can be trivially realized by independent operators in the effective action. We use this to show that the possible pure (real and complex) scalar, fermion, and vector exceptional EFTs are highly constrained. Next, we prove how the soft behavior of states in a supermultiplet must be related and illustrate the results in extended supergravity. We demonstrate the power of the soft bootstrap in two applications. First, for the N= 1 and N=2 CP^1 nonlinear sigma models, we show that on-shell constructibility establishes the emergence of accidental IR symmetries. This includes a new on-shell perspective on the interplay between N=2 supersymmetry, low-energy theorems, and electromagnetic duality. We also show that N=2 supersymmetry requires 3-point interactions with the photon that make the soft behavior of the scalar O(1) instead of vanishing, despite the underlying symmetric coset. Second, we study Galileon theories, including aspects of supersymmetrization, the possibility of a vector-scalar Galileon EFT, and the existence of higher-derivative corrections preserving the enhanced special Galileon symmetry. This is addressed by soft bootstrap and by application of double-copy/KLT relations applied to higher-derivative corrections of chiral perturbation theory.Comment: 71 pages, no figures. v2: significant new material about the N=2 CP^1 NLSM; typos correcte

Scattering Amplitudes and N-Body Post-Minkowskian Hamiltonians in General Relativity and Beyond

We present a general framework for calculating post-Minskowskian, classical, conservative Hamiltonians for $N$ non-spinning bodies in general relativity from relativistic scattering amplitudes. Novel features for $N>2$ are described including the subtraction of tree-like iteration contributions and the calculation of non-trivial many-body Fourier transform integrals needed to construct position space potentials. A new approach to calculating these integrals as an expansion in the hierarchical limit is described based on the method of regions. As an explicit example, we present the $\mathcal{O}\left(G^2\right)$ 3-body momentum space potential in general relativity as well as for charged bodies in Einstein-Maxwell. The result is shown to be in perfect agreement with previous post-Newtonian calculations in general relativity up to $\mathcal{O}\left(G^2 v^4\right)$. Furthermore, in appropriate limits the result is shown to agree perfectly with relativistic probe scattering in multi-center extremal black hole backgrounds and with the scattering of slowly-moving extremal black holes in the moduli space approximation.Comment: 41 pages, 5 figure

Rewilding – departures in conservation policy and practice? An evaluation of developments in Britain

Rewilding has been hailed as ‘radical’ and ‘agenda-setting’ in the challenge it poses to mainstream conservation. This paper questions whether that is still the case, or if rewilding is now being mainstreamed and with what consequences? Our analysis focuses upon developments in Britain, up until 2018, discussing what changes have become manifest and the barriers and restraints that have been observed. As such, we evaluate the extent to which rewilding – in practice - departs from longstanding conservation sensibilities. Discussion is structured around three key questions— Who is now involved in rewilding across Britain? What they are seeking to do, in terms of how nature is conceptualised and managed (or not)? In what ways do their objectives involve people and human-centred aspirations? Our findings reveal three key differences from current conservation approaches. First, rewilding is associated with a proliferation of new actors, new mechanisms of finance and new spaces of conservation interest. Second, rewilding as an approach exhibits clear novelty in its stated aim to be nature-led and, despite challenges, attempts to work through ongoing negotiation and experimentation. Finally, rewilding is currently being advocated and pursued as an agenda for people and nature, which moves beyond earlier nature conservation paradigms of protecting nature from human influence. However, it remains to be seen whether rewilding advocates can realise their ambitions to popularise and create peopled wild spaces across Britain's landscapes