An Examination of the Interaction Between Modelling and Its Relationship with Construction Kits: Lessons from the Past and for the Future

Construction kits have played a significant part in nurturing the growth and development of the minds and manipulation-based skills of children (and adults) in formal and non-formal education settings. These kits have origins rooted in the representation of the built world and now have a diversity of form and function, including technical versions with moving parts. This article examines some of the historically based ideas that lie behind the role that kits may have in terms of physical modelling. The article traces the transformation of kits from simple bricks and blocks into more complicated pieces for space-filling and achieving the transfer of forces and motion. This transformation occurred during the Victorian era when the influence of the ideas of educationalists and, perhaps rather strangely, exponents of early aviation, played major roles in determining the diversity of forms of construction kit and modelled possibilities that are now to be seen in classrooms and homes. The article ends with a review of some of the lessons from the past and present that will need to be considered in relation to concrete modelling in schools for the future. This revised version was published online in July 2006 with corrections to the Cover Date.     

The Impact of the Implementation of Technology Education on In-Service Teacher Education in South Africa (Impact of Technology Education in the RSA)

In this article the impact of technology education, as a new learning area (subject) in the curriculum, on in-service teacher education in South Africa is described in order to ascertain the extent of the impact. The research on which this article is based draws on a variety of experiences and observations in the field at grassroots level (in particular an outreach project in rural communities). The envisaged impact of technology education on South African schools, communities, teacher educators and teachers, the range of in-service teacher education that is required, and the impacts in urban and rural areas are discussed. Finally a number of concluding remarks are made about the extent of the impact of the inclusion of technology education in the new National Curriculum Statement and whether the situation has changed since the implementation of a pilot technology education project in 1998. This revised version was published online in July 2006 with corrections to the Cover Date.     

Relative risk aversion, relative prudence and comparative statics under uncertainty: The case of (μ, σ)‐preferences

From the expected‐utility approach, relative risk aversion being smaller than one and relative prudence being smaller than two emerge as preference restrictions that fully determine the optimal responses of decisions under uncertainty to certain shifts in probability distributions. We characterize the magnitudes of relative risk aversion and relative prudence in terms of the two‐parameter, mean‐standard deviation approach. We demonstrate that this characterization is instrumental in obtaining comparative static results in the two‐parameter setting. We further relate our findings to the results in the expected‐utility framework.     

Economic Implications of Alternative Allocation Schemes for Emission Allowances*

For reasons of political feasibility, emission trading systems may have to rely on free initial allocation of emission allowances in order to ameliorate adverse production and employment effects in dirty industries. Against the background of an emerging European‐wide emission trading system, we examine the trade‐off between such compensation and economic efficiency under output‐based and emissions‐based allocation rules. We show that the emissions‐based allocation rule is more costly than the output‐based rule in terms of maintaining output and employment in energy‐intensive industries. When the international allowance price increases, the inferiority of emissions‐based allocation vis‐à‐vis output‐based allocation becomes more pronounced, as emission subsidies drastically restrict efficiency gains from international trade in emission allowances.     

Lies,damned lies and statistics: the accuracy of survey responses

That survey research is error prone is not a new idea and different varieties of non-sampling error have been investigated in the literature as well as consideration being given in many statistics textbooks to the issue of sampling error. The paper here considers research upon corporate environmental reporting. It compares information provided by corporate environmental reports with information that survey respondents claim their organization’s environmental report contains. This enables the accuracy of the claims to be assessed. Consideration is given to two different industries the Water industry and the Energy industry. Errors due to inaccurate reporting by survey respondents are shown to be relatively infrequent and respondents appear just about as likely to claim they report information that they do not, in fact, report as to fail to indicate that they report information that is, in fact, actually reported.