Future harvest : the fine line between myopia and utopia

Inaugural lecture upon taking up the post fo Personal Professor of Plant Production Systems at Wageningen University on 12 May 2011

When is the Bloch-Okounkov q-bracket modular?

We obtain a condition describing when the quasimodular forms given by the Bloch-Okounkov theorem as $q$-brackets of certain functions on partitions are actually modular. This condition involves the kernel of an operator {\Delta}. We describe an explicit basis for this kernel, which is very similar to the space of classical harmonic polynomials.Comment: 12 pages; corrected typo

Quantitative Results on Diophantine Equations in Many Variables

We consider a system of integer polynomials of the same degree with non-singular local zeros and in many variables. Generalising the work of Birch (1962) we find quantitative asymptotics (in terms of the maximum of the absolute value of the coefficients of these polynomials) for the number of integer zeros of this system within a growing box. Using a quantitative version of the Nullstellensatz, we obtain a quantitative strong approximation result, i.e. an upper bound on the smallest integer zero provided the system of polynomials is non-singular.Comment: Accepted for publication in Acta Arithmetica. Added a few pages so that familiarity with Birch's work is no longer assumed; 24 page

Crop models: main developments, their use in CGMS and integrated modeling

Het artikel beschrijft de voornaamste ontwikkelingen in gewasgroeimodellen (WOFOST), hun gebruik in CGMS en geïntegreerde modellerin

Consumer Food Safety Risk Attitudes and Perceptions Over Time: The Case of BSE Crisis

Recent research has shown that by decoupling the risk response behaviour of consumers into the separate components of risk perception and risk attitude, a more robust conceptualization and prediction of consumers’ reactions to food safety issues is possible. Furthermore, it has been argued that the influence of risk attitudes and risk perceptions on consumer risk behaviour for contaminated food products can be used to formulate effective agricultural policies and strategies in case of a food crisis. The question arises whether or not the influence and magnitude of these risk variables changes over time and, hence, whether policies and strategies must be adapted. The BSE (mad cow disease) crises in the USA, Germany and The Netherlands in 2001 and 2004 provided us with a natural experiment to examine the relationship between risk attitudes and perceptions and behaviour over time. The results show that in some countries consumers risk behaviour changed, whereas in others not. These results are useful to policy makers and decision makers in food industry in developing more efficient supply chain management and public policies

Assessing farmer behaviour as affected by policy and technological innovations: bio-economic farm models

Farm Management,

Consumer Food Safety Risk Attitudes and Perceptions Over Time: The Case of BSE Crisis

Recent research has shown that by decoupling the risk response behaviour of consumers into the separate components of risk perception and risk attitude, a more robust conceptualization and prediction of consumers’ reactions to food safety issues is possible. Furthermore, it has been argued that the influence of risk attitudes and risk perceptions on consumer risk behaviour for contaminated food products can be used to formulate effective agricultural policies and strategies in case of a food crisis. The question arises whether or not the influence and magnitude of these risk variables changes over time and, hence, whether policies and strategies must be adapted. The BSE (mad cow disease) crises in the USA, Germany and The Netherlands in 2001 and 2004 provided us with a natural experiment to examine the relationship between risk attitudes and perceptions and behaviour over time. The results show that in some countries consumers risk behaviour changed, whereas in others not. These results are useful to policy makers and decision makers in food industry in developing more efficient supply chain management and public policies.consumer risk behaviour, food safety, risk attitude, risk perception, time, Food Consumption/Nutrition/Food Safety,