Consumer shopping behavior: how much do consumers save?

This paper documents the potential and actual savings that consumers realize from four particular types of purchasing behavior: purchasing on sale; buying in bulk (at a lower per unit price); buying generic brands; and choosing outlets. How much can and do households save through each of these behaviors? How do these patterns vary with consumer demographics? We use data collected by a marketing firm on all food purchases brought into the home for a large, nationally representative sample of U.K. households in 2006. We are interested in how consumer choice affects the measurement of price changes. In particular, a standard price index based on a fixed basket of goods will overstate the rise in the true cost of living because it does not properly consider sales and bulk purchasing. According to our measures, the extent of this bias might be of the same or even greater magnitude than the better-known substitution and outlet biases

Sheep CRC Renewal Proposal: Economic Evaluation of the Proposed Scientific Themes

The Australian sheep industry and its associated research and development agencies have developed a proposal for the CRC for Sheep Industry Innovation. “Top-down” and “bottomup” procedures were used to assess the expected economic benefits from this proposal. Formal “with-CRC” and “without-CRC” scenarios were defined for each product and each research theme. Relevant costs were similarly defined. The requested investment by the Commonwealth and the Australian sheep industry in the CRC is assessed relative to a scenario where an alternative, lower cost research program into this industry is implemented. These extra resources have a discounted value of about $34 million over the 25-year period of this evaluation. These resources are sufficient to allow some new research components to be added to the portfolio, some existing components to produce better outcomes, and a more targeted approach to development and extension that speeds up and increases the adoption of the new technologies that are generated by the research program. The benefit from this extra investment and consequent research effort is estimated to be worth about$518 million in present value terms, which is far in excess of the marginal investment. Thus every $1 of these extra resources brought into the Australian sheep industry through funding the proposed CRC is expected to return around$15.30 to the industry in present value terms.wool, sheep meat, research and development, economic, evaluation, Australia, Agribusiness, Livestock Production/Industries, Production Economics, Research and Development/Tech Change/Emerging Technologies, Q160,

Economic benefits of public investment in weed management: the case of vulpia in south-eastern Australia’s temperate pasture areas

The present paper reports an economic evaluation of the long-term benefits to Australia of research by the Cooperative Research Centre for Weed Management Systems (CRC) into the improved management of vulpia , the major annual grass weed of temperate pastures in New South Wales and Victoria. Vulpia reduces livestock production by competition with more desirable pasture species, by the production of low quality feed at critical times of the grazing cycle, and by injury to animals. A 20-year stochastic benefit-cost analysis indicated that reducing the impacts of vulpia in these pastures produced a mean net present value of # A58.3 million and a mean benefit-cost ratio of 33:1. Temperate pasture zone wool producers would capture the largest shares of these benefits, Australian consumers would gain, but wool producers in the rest of Australia would suffer welfare losses from vulpia reductions in the temperate pasture zones.Agricultural and Food Policy, Farm Management,

Inertial Coupling Method for particles in an incompressible fluctuating fluid

We develop an inertial coupling method for modeling the dynamics of point-like 'blob' particles immersed in an incompressible fluid, generalizing previous work for compressible fluids. The coupling consistently includes excess (positive or negative) inertia of the particles relative to the displaced fluid, and accounts for thermal fluctuations in the fluid momentum equation. The coupling between the fluid and the blob is based on a no-slip constraint equating the particle velocity with the local average of the fluid velocity, and conserves momentum and energy. We demonstrate that the formulation obeys a fluctuation-dissipation balance, owing to the non-dissipative nature of the no-slip coupling. We develop a spatio-temporal discretization that preserves, as best as possible, these properties of the continuum formulation. In the spatial discretization, the local averaging and spreading operations are accomplished using compact kernels commonly used in immersed boundary methods. We find that the special properties of these kernels make the discrete blob a particle with surprisingly physically-consistent volume, mass, and hydrodynamic properties. We develop a second-order semi-implicit temporal integrator that maintains discrete fluctuation-dissipation balance, and is not limited in stability by viscosity. Furthermore, the temporal scheme requires only constant-coefficient Poisson and Helmholtz linear solvers, enabling a very efficient and simple FFT-based implementation on GPUs. We numerically investigate the performance of the method on several standard test problems...Comment: Contains a number of corrections and an additional Figure 7 (and associated discussion) relative to published versio

Effect of prolonged space flight on cardiac function and dimensions

Echocardiographic studies were performed preflight 5 days before launch and on recovery day and 1, 2, 4, 11, 31 and 68 days postflight. From these echocardiograms measurements were made. From these primary measurements, left ventricular end-diastolic volume, end-systolic volume, stroke volume, and mass were derived using the accepted assumptions. Findings in the Scientist Pilot and Pilot resemble those seen in trained distance runners. Wall thickness measurements were normal in all three crewmembers preflight. Postflight basal studies were unchanged in the Commander on recovery day through 68 days postflight in both the Scientist Pilot and Pilot, however, the left ventricular end-diastolic volume, stroke volume, and mass were decreased slightly. Left ventricular function curves were constructed for the Commander and Pilot by plotting stroke volume versus end-diastolic volume. In both astronauts, preflight and postflight data fell on the same straight line demonstrating that no deterioration in cardiac function had occurred. These data indicate that the cardiovascular system adapts well to prolonged weightlessness and suggest that alterations in cardiac dimensions and function are unlikely to limit man's future in space

Probability distributions for economic surplus changes: the case of technical change in the Australian wool industry

Mullen, Alston and Wohlgenant (1989) (MAW) examined the distribution of the benefits of technical change in the Australian wool industry. Their conclusions are revisited by examining the probability distributions of changes in the welfare measures, given uncertainty about their model parameters. Subjective probability distributions are specified for the parameters and correlations among some of the parameters are imposed. Hierarchical distributions are also used to model diverse views about the specification of the subjective distributions. A sensitivity elasticity is defined through the estimation of a response surface to measure the sensitivity of the estimated research benefits to individual parameters. MAW’s conclusions are found to be robust under the stochastic approach to sensitivity analysis demonstrated in this article.Livestock Production/Industries,

Dynamic general equilibrium analysis of improved weed management in Australia's winter cropping systems

A recent analysis indicated that the direct financial cost of weeds to Australia’s winter grain sectorwas approximately $A1.2bn in 1998–1999. Costs of thismagnitude represent a large recurring productivity loss in an agricultural sector that is sufficient to impact significantly on regional economies.Using amulti-regional dynamic computable general equilibrium model, we simulate the general equilibrium effects of a hypothetical successful campaign to reduce the economic costs of weeds. We assume that an additional$50m of R&D spread over five years is targeted at reducing the additional costs and reduced yields arising from weeds in various broadacre crops. Following this R&D effort, one-tenth of the losses arising from weeds is temporarily eliminated, with a diminishing benefit in succeeding years. At the national level, there is a welfare increase of $700m in discounted net present value terms. The regions with relatively high concentrations of winter crops experience small temporary macroeconomic gains.CGE modelling, dynamics, weed management, Crop Production/Industries,