Discrete choice surveys by telephone

In two consumer studies, discrete choice surveys were administered both by telephone and by traditional pencil and paper methods. Study participants responded to discrete choice surveys concerning pizza restaurants in the first study and fast food restaurants in the second. Neither aggregate level estimated utilities for the pizza restaurants, nor market shares for the fast food restaurants differed by method of administration. The results indicate that discrete choice surveys can be successfully administered by telephone. He received his Ph.D. in marketing from the University of Texas at Dallas. Dr. Perkins is interested in marketing research methodology and in the use of marketing research information in managerial decision making. Dr. Perkins has published articles in theJournal of Marketing Research andPsychometrika. He is a member of the American Marketing Association, the Marketing Research Association, and the TIMS College of Marketing. Jacqueline Roundy recently completed the M.S. degree in marketing from the Pennsylvania State University. In addition she holds an M.B.A. from the University of Utah. She is currently working in Europe.     

Maximising sustainability of Dutch dairy farming systems for different stakeholders: A modelling approach

A multi-attribute sustainability function is included into a dairy farm LP-model by using Weighted Goal Programming. The created Weighted Linear Goal Programming (WLGP)-model is used to maximise sustainability of different Dutch dairy farming systems and to analyse the impact of: (1) maximisation of individual sustainability aspects (economic, social and ecological sustainability) and (2) maximisation of overall sustainability using stakeholder preferences. Maximising the individual aspects of both dairy farming systems, i.e. conventional and organic, shows the trade-offs between different aspects of sustainability. For conventional as well as organic dairy farming maximum scores are highest for external social sustainability. The conventional dairy farm achieves a slightly higher score for overall sustainability than the organic dairy farm for all stakeholders (i.e. consumers and producers). This shows that it is possible for conventional dairy farms, similar to the conventional farm used in the analysis especially regarding the stocking density and under Dutch policy conditions, to achieve equal sustainability scores in comparison with organic dairy farms. It is concluded that the WLGP model is a suitable tool to analyse the sustainability of different dairy farming systems.     

Descriptive statistics of large data sets by scatter plots, an exploratory approach

In the analysis of large tables of M variables on N observations one is interested in the relations between the variables and it is usual to inspect the M(M-1)/2 scatter plots of N points. Clearly, the scatter plot approach relies on visual inspection and is to be preferred in so far as applicable to detect simple relations, namely when M is small. Other approaches are needed for large values of M .
We consider that only the relatively few scatter plots that present a 'structure' are of interest for an exploratory analysis and, by 'structure', we mean a domain of specially high local density in the plot. Based on this concept, we propose a method constructed around two steps: the selection of the possibly interesting pairs of variables and the validation of the corresponding scatter plots. The selection of the pairs results from an algorithm based on a binary partitioning tree. The validation of the corresponding scatter plots enables the production of only those where a structure is found the recognition of a structure is derived from a statistic based on the length of the Minimum Spanning Tree constructed on the N points of the candidate scatter plot.
For illustration, we report on an industrial application where the method is routinely applied for exploratory purposes.     

Evolution of urban housing stocks: A model applied to Baltimore and Houston

Historical simulations of urban residential growth in Baltimore and Houston based on a model of the growth process which has two distinct components are presented. The vintage component utilizes the growth of income and population, and an assumption that housing is putty-clay, to predict the age distribution of the housing stock in each period. The spatial component of the model determines where this housing construction will take place according to (1) housing is built on vacant land and (2) the pattern of construction obeys the rules of the standard monocentric models. Housing is demolished when economically obsolete. The putty-clay (vintage) aspect of the model produces fairly accurate city-wide vintage distributions, but there is much more mixing of vintages and income (in Baltimore) by location than predicted, even under monocentric assumptions most favorable to mixing.     

A Bug Is a Bug Is a Bug: Symbolic Responses to Contingent Valuation Questions about Forest Pest control programs?

Symbolic responses are one of many issues attending contingent valuation studies. The problem is that many objects that are the subject of contingent valuation surveys can act as symbols for larger issues. In this paper, we want to compare the attitudes of residents of five communities with two different forest pests, jack pine budworm and gypsy moth. Jack pine budworm affects commercially important forests in Canada, while gypsy moth generally affects recreational areas and has less commercial significance. All of the respondents were asked about both insects; however, not all of the communities had direct experience with both insects. The purpose is to examine whether respondents would differentiate their willingness to pay for control mechanisms between these different defoliators. The implication is that all bugs are alike and generally noxious, a notion that would not necessarily sit well with resource managers who have to deal with insect outbreaks. Respondents did not differentiate strongly between insect control programs that would impact their community and those that would not. While not conclusive, the results do suggest symbolic responses to this particular issue. This is further evidence that willingness-to-pay results from contingent valuation studies need to be cautiously interpreted as pseudo market values.     

Comparative Advantage in Demand: Experimental Evidence of Preferences for Genetically Modified Food in the United States and European Union

The United States (US) exports more than US$6 billion in agricultural commodities to the European Union(EU) each year, but one issue carries the potential to diminish this trade: use of biotechnology in food production. The EU has adopted more stringent policies towards biotechnology than the US. Understanding differences in European and American policies towards genetically modified (GM) foods requires a greater understanding of consumers’ attitudes and preferences. This paper reports results from the first large‐scale, cross‐Atlantic study to analyse consumer demand for genetically modified food in a non‐hypothetical market environment. We strongly reject the frequent if convenient assumption in trade theory that consumer preferences are identical across countries: the median level of compensation demanded by English and French consumers to consume a GM food is found to be more than twice that in any of the US locations. Results have important implications for trade theory, which typically focuses on differences in specialization, comparative advantage and factor endowments across countries, and for on‐going trade disputes at the World Trade Organization.     

Carbon sequestration and farm income in West Africa: Identifying best management practices for smallholder agricultural systems in northern Ghana

The interest in agricultural soils as global storage of carbon has increased in recent years, along with the prospect of farmers' participation in payment schemes under the Clean Development Mechanism of the Kyoto protocol. Thus, a better understanding of agricultural practices that can increase soil carbon and enhance the livelihoods of farmers is necessary, particularly in smallholder farming systems of West Africa. This study evaluates different crop management strategies both by their capacity to sequester carbon in agricultural soils and by their contribution to household income. A case study in Wa, Upper West Region of Ghana is used to test 48 different cropping strategies by means of a crop simulation model and a household-level multiple-criteria optimisation model. Each cropping strategy is evaluated after a 20-year simulation period by its capacity to accrue carbon in the soil, by its economic performance at the plot-level, and by its contribution to the farm income with and without carbon payments. A set of best management practices that concomitantly increase soil carbon and farm income are identified and classified by their cost of investment.