A Paradigm for Masking (Camouflaging) Information

This is an expository paper. Here we propose a decision-theoretic framework for addressing aspects of the confidentiality of information problems in publicly released data. Our basic premise is that the problem needs to be conceptualized by looking at the actions of three agents: a data collector, a legitimate data user, and an intruder. Here we aim to prescribe the actions of the first agent who desires to provide useful information to the second agent, but must protect against possible misuse by the third. The first agent is under the constraint that the released data has to be public to all; this in some societies may not be the case.
A novel aspect of our paper is that all utilities—fundamental to decision making—are in terms of Shannon's information entropy. Thus what gets released is a distribution whose entropy maximizes the expected utility of the first agent. This means that the distribution that gets released will be different from that which generates the collected data. The discrepancy between the two distributions can be assessed via the Kullback–Leibler cross-entropy function. Our proposed strategy therefore boils down to the notion that it is the information content of the data, not the actual data, that gets masked. Current practice of "statistical disclosure limitation" masks the observed data via transformations or cell suppression. These transformations are guided by balancing what are known as "disclosure risks" and "data utility". The entropy indexed utility functions we propose are isomorphic to the above two entities. Thus our approach provides a formal link to that which is currently practiced in statistical disclosure limitation.     

On the need for more economic assessment of quarantine policies

Quarantine policy reviews are becoming more sophisticated yet they still focus primarily on the effects of restrictions solely on import-competing producers. A fuller analysis that includes the consumers demonstrates that even if imported diseases were to wipe out a local industry, the gains to consumers might outweigh the losses to import-competing producers from removing a ban on imports. This article provides the simplest partial equilibrium framework for thinking more about the economics of quarantine policy measures using an empirical analysis of Australia's ban on imports of bananas.     

Consumer preferences for GM food and other attributes of the food system

While qualitative surveys regarding consumers' attitudes about gene technologies and their application to food production are plentiful, quantitative studies are less so. The present paper reports choice modelling methods to examine the conditions under which Australian consumers are willing to purchase genetically modified (GM) foods, if at all, and examines those preferences within the context of the food system as a whole. This allows us to compare consumer attitudes towards gene technology to consumer preferences for other features of the food they consume. The results of the choice modelling analysis suggest consumers require a discount on their weekly food bill before they will purchase GM food. Gene technology using animal as well as plant genes was found to be more objectionable to respondents than that using plant genes alone, especially among women. Age seems to affect the preferences for a certain type of food, with older people generally more accepting of the use of gene technology.