THE RELATIONSHIP BETWEEN FARM SIZE AND THE TECHNICAL INEFFICIENCY OF PRODUCTION OF WHEAT FARMERS IN THE EASTERN FREE STATE

Some comments are required to put in perspective the results obtained by Ngwenya, Battese and Fleming (1997). In particular, it is necessary to examine their main conclusion that in 1988/89 there was a significant inverse relationship between the technical inefficiency of wheat farmers in the Eastern Free State and farm size, because this is in direct contrast with the findings of Van Zyl, Binswanger and Thirtle (1995) who used the same dataset.Crop Production/Industries,

Cross sections for ionization in collisions between excited nitrogen molecules and argon atoms, oxygen molecules, and nitric oxide molecules

Ionization cross sections in collisions between excited nitrogen molecules and argon atoms, oxygen molecules, and nitric oxide molecule

Cross sections for ionization in collisions between excited nitrogen molecules and carbon monoxide and nitrogen ground-state molecules

Cross sections for ionization in collisions between excited nitrogen molecules and carbon monoxide and nitrogen ground state molecule

Diagnosis and Treatment of Diabetic Ketoacidosis

Diabetic ketoacidosis (DKA) is the most frequent hyperglycaemic acute diabetic complication. Furthermore it carries a significant risk of death, which can be prevented by early and effective management. All physicians, irrespective of the discipline they are working in and whether in primary, secondary or tertiary care institutions, should be able to recognise DKA early and initiate management immediately. South African Family Practice Vol. 50 (1) 2008: pp. 35-3

Assessing the benefits of research expenditures on maize production in South Africa

This paper focuses on assessing the benefits of research expenditures on maize production in South Africa. Both the production and supply function approaches are used to calculate elasticities of research expenditure on output and yield. Cointegration is used to establish long-run relationships between variables in these models. The lag structure of R&D expenditures on output is examined making use of the unrestricted, polynomial, beta and gamma distributions. The coefficients of these lag distributions were then used to calculate a rate of return to maize research expenditure, which was estimated as being between 28% and 39% per annum. These rates of return are high, mitigating in favour of more research expenditure rather than less.Crop Production/Industries, Research and Development/Tech Change/Emerging Technologies,

Constructing a Sophistication Index as a Method of Market Segmentation of Commercial Farming Businesses in South Africa

This study investigates the process of index construction as a means of measuring a hypothetical construct that can typically not be measured by a single question or item and applying it as a method of market segmentation. The availability of incidental secondary data provided a relevant quantitative basis to illustrate this process by constructing a commercial farming sophistication index for South Africa. It was evident that this approach offers an appropriate and useful means of segmenting a market. Several factors contribute to the appeal of this approach. Among others, it addresses important priorities in the area of future segmentation research. By offering classification rules based on characteristics that can easily be observed or elicited through asking a few key questions, new or potential buyers can be grouped by buying behaviour segment. Furthermore, the multi-step process that was employed provides a systematic and structured multivariate approach to segmentation. It also facilitates replication of the process when conducting future studies. Lastly, the outcome of this type of segmentation method offers researchers and marketing practitioners a procedure, in the form of an equation, to calculate index scores and provide rules to segment the market based on predefined intervals. Hence, the challenge to replicate segment formation across independent future studies is addressed.Keywords: Agribusiness, Commercial Farming, Index Construction, Segmentation, Sophisticatio

Magnetoplasmon excitations in an array of periodically modulated quantum wires

Motivated by the recent experiment of Hochgraefe et al., we have investigated the magnetoplasmon excitations in a periodic array of quantum wires with a periodic modulation along the wire direction. The equilibrium and dynamic properties of the system are treated self-consistently within the Thomas-Fermi-Dirac-von Weizsaecker approximation. A calculation of the dynamical response of the system to a far-infrared radiation field reveals a resonant anticrossing between the Kohn mode and a finite-wavevector longitudinal excitation which is induced by the density modulation along the wires. Our theoretical calculations are found to be in excellent agreement with experiment.Comment: 9 pages, 8 figure

Machinery and labour biases of technical change in South African agriculture: A cost function approach

This paper provides an empirical investigation into the long-standing notion of biases of technical change in South African agriculture. The second order cost function is used to derive relative bias measures between labour and machinery. The results suggest that large machinery-using biases in technology have been developed with minimal labour-using biases.Farm Management, Research and Development/Tech Change/Emerging Technologies,

A study of single-gender grouping for sixth grade math as a strategy for improving student achievement

Title from PDF of title page (University of Missouri--Columbia, viewed on May 31, 2012).The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file.Dissertation advisor: Dr. Jerry ValentineVita.Ph. D. University of Missouri-Columbia 2011."December 2011"Purpose of the study. The purpose of this study was to examine single-gender groupings for sixth grade mathematics classes as a strategy to improve student achievement. The method of research was quantitative, with MAP mathematics test data being used to determine if any relationship exists between the strategy and student achievement. Findings. From this study a firm conclusion about the value of single-gender classes is problematic. While the experimental group appeared to make a difference in the basic statistical analyses, the fact that the findings were not significant when a proxy measure for poverty (free and reduced lunch) and gender are both added to the statistical formulae raise substantial concerns about the value of single-gender classes. Further research is needed to better clarify the true value of single-gender classes compared to mixed-gender issues.Includes bibliographical reference

Female perceptions on employment equity: is the glass ceiling cracking?

The primary objective of this study was to assess if there were any perceptual differences between gender groups regarding employment equity practices. A sample of 4729 participants from different companies and industries completed the Employment Equity Questionnaire. Results from an ANOVA indicated that there were significant differences between gender groups, but only a small portion of the variance was explained by perceptual differences on employment equity practices. The instrument thus possesses some discriminant validity. Further analyses on an item level indicated that there were significant differences between gender groups, but these differences were not attributable to gender stereotypes. Specific employment equity practices were identified that need closer attention from management’s side to address gender discrimination