Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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    Agent-Based Simulation of Local Soy Value Chains in Ghana
    Verwaart, Tim ; Dijkxhoorn, Youri ; Plaisier, Christine ; Wagenberg, Coen Van - \ 2019
    In: Progress in Artificial Intelligence. - Springer (Progress in Artificial Intelligence ) - ISBN 9783030302436 - p. 654 - 666.
    The assessment of changes in the relationships between supply chain agents is considered fundamental for market transformation. This paper reports on the application of a Value Chain Lab that supports the measurement of behavioral change in vertically structured supply-chain relationships. A participative gaming approach is used that enables to identify changes in mutual trust, transaction costs and risk behavior that result from value chain support and co-operation. The Value Chain Lab comprises value chain analysis, value chain games and multi-agent simulation. The paper describes the multi-agent simulation of a soy value chain in northern Ghana. The research was conducted in the context of the 2SCALE program, aiming to improve rural livelihoods and food and nutrition security in a number of African countries by developing agricultural supply chains including local smallholder farmers. The study confirms the positive effects of trust and loyalty in value chain relationships. Furthermore, it demonstrates the usefulness of agent-based simulations for exploring potential consequences of alternative interventions.
    The Lemon Car Game Across Cultures: Evidence of Relational Rationality
    Hofstede, G.J. ; Jonker, Catholijn ; Verwaart, T. ; Yorke-Smith, Neil - \ 2019
    Group Decision and Negotiation 28 (2019)5. - ISSN 0926-2644 - p. 849 - 877.
    Negotiation - Culture - Experimental studies - Power distance - Long-term orientation - Lemon car
    In cross-cultural business negotiation, culture is known to influence negotiation processes. As a lens to study this effect we deployed the Lemon Car Game, an online negotiation game developed for this purpose (Hofstede et al. in: Proceedings of 39th international simulation and gaming association conference (ISAGA). Technologia, Kaunas, pp 39–46, 2009a; Hofstede et al. in: David, Sichman (eds) Multi-agent-based simulation IX, international workshop, MABS 2008, revised selected papers, LNAI 5269. Springer, Berlin, pp 1–16, 2009b). In this article we report the results from the game, obtained from over 800 players from more than 70 countries. We employ several complementary analyses in a mixed-methods approach.Our findings show that to make sense of the players’ actions during negotiation, economic rationality falls short. A pan-cultural individual-level analysis of actions and stated intentions also fails to yield a coherent picture. Within countries, however, actions and intentions do cohere, as shown by an ecological country-level factor analysis, from which three factors emerge for the sellers at country level: trustworthiness, opportunism, and fairness. We conclude from these findings that, in this game, players are driven by what we call relational rationality: they are rational from the perspective of the social world in which they live, with interpersonal relationships weighing heavily. Relational rationality changes players’ perspective of economic rationality, and thus their observed behaviour in negotiation. Based on this evidence, we extrapolate that relational rationality significantly influences negotiation processes in all cultures.
    A reference architecture for IoT-based logistic information systems in agrifood supply chains
    Verdouw, C.N. ; Robbemond, R.M. ; Verwaart, T. ; Wolfert, J. ; Beulens, A.J.M. - \ 2018
    Enterprise information systems 12 (2018). - ISSN 1751-7575 - p. 755 - 779.
    Logistics in the food and agribusiness industry must address perishable products, unpredictable supply variations and stringent food safety and sustainability requirements. The Internet of Things (IoT) could contribute significantly to solve these challenges because it allows for remotely controlling the location and conditions of shipments and products. This paper develops a reference architecture for IoT-based logistic information systems in agri-food supply chains. It proposes a hybrid solution that combines the IoT and cloud computing. The architecture supports the provision of affordable tailor-made solutions by utilising technology enablers of the European Future Internet programme and by facilitating the reuse of domain-specific functionalities.
    Value chain laboratory : alternative evaluation method for assessing value chain dynamics
    Dijkxhoorn, Youri ; Plaisier, Christine ; Wagenberg, Coen van; Verwaart, Tim ; Verstegen, Jos ; Ruben, Ruerd ; Oldenhof, Ruben - \ 2017
    Wageningen : Wageningen Eonomic Research (Wageningen Eonomic Research report 2017-031) - ISBN 9789463436465 - 75
    How social unrest started innovations in a food supply chain
    Buurma, Jan ; Hennen, Wil ; Verwaart, Tim - \ 2017
    Journal of Artificial Societies and Social Simulation 20 (2017)1. - ISSN 1460-7425
    Content analysis - Dramaturgical analysis - Food supply chain - Opinion dynamics - Sociotechnical innovation

    Transitions leading to sociotechnical innovations in food supply chains have been described in dramaturgical analyses on the basis of newspaper articles and parliamentary records. The time scale of the transitions driven by aroused public opinion on issues such as animal welfare, is typically a decade. Actors are primary producers (farmers), other supply chain parties, authorities, NGOs voicing particular opinions, political parties, and consumers. In this article, their interactions and reactions to external events are modelled in an agent-based simulation based on opinion dynamics. The purposes of the simulation are (1) to validate that hypothetical relations derived from the dramaturgical analysis indeed lead to the emergence of the observed transitions, and (2) to study how the system could have developed under different behaviours or a different course of external events. Simulation results and a sensitivity analysis are discussed.

    Simulating the role of trust in supply development
    Verwaart, T. ; Dijkxhoorn, Y. ; Plaisier, Christine ; Wagenberg, C.P.A. van - \ 2016
    - 12 p.
    Fostering of inclusive business aiming to involve low-income communities
    in value chains is a recent approach to alleviate poverty in developing countries.
    The approach requires new impact assessment tools to measure changes in
    farm income and transaction cost, and behavioural change in value chain relationships.
    An agent-based simulation combined with games is proposed for the
    assessment of a project developing sorghum production and marketing in Meru
    County, Kenya. Contracts between a local sorghum processor and smallholders
    have a central role. Trust between farmers and the processor and mutual trust in
    farmer groups are key success factors. The simulations indicate that the approach
    can lead to increased farm incomes. Continuity of the contract system depends on
    the extent to which contracted farmers can be trusted not to side-sell when market
    prices are high. However, the simulated production remains at an increased level
    even if the contract system breaks down.
    An updated generic architecture describingcompliance in Agri-Food Supply Chains : (D1.2.3)
    Kruize, J.W. ; Robbemond, R.M. ; Verwaart, T. - \ 2016
    Wageningen : LEI Wageningen UR (Report / LEI Wageningen UR 2016-061) - ISBN 9789462578289 - 21
    agro-industrial chains - food chains - food supply - computer software - efficiency - business economics - agro-industriële ketens - voedselketens - voedselvoorziening - computer software - efficiëntie - bedrijfseconomie
    In this report a generic architecture is presented comprising an inventory of the most important actors, roles, processes and information that are relevant in the processes of standardisation, certification and compliance in Agri-Food Supply Chains. This architecture becomes part of an architectural framework. The architectural framework aims to reduce the paper -based administration by improving digitalisation of compliance processes and to enable a more efficient and effective data exchange in the field of compliance.
    HortiCube: A Platform for Transparent, Trusted Data Sharing in the Food Supply Chain
    Verhoosel, J. ; Bekkum, M. van; Verwaart, T. - \ 2016
    - 5 p.
    Compliance in Agri Food Supply Chains
    Kruize, Jan Willem - \ 2015
    i.s.m. Robbert Robbemond, Youri Dijkxhoorn en Tim Verwaart
    Big Data opportunities for marketing of horticultural products
    Verwaart, Tim - \ 2015
    Agent-based simulation of competing sustainability enhancing strategies for the pork supply chain
    Verwaart, T. ; Broek, E.M.F. van den - \ 2015
    - p. 11 - 11.
    How Social Unrest Started Innovations in Food Supply Chains: Simulation of Opinion Dynamics
    Buurma, J.S. ; Hennen, W.H.G.J. ; Verwaart, T. - \ 2015
    - p. 12 - 12.
    Transitions leading to sociotechnical innovations in food supply chains have been described in dramaturgical analyses on the basis of newspaper articles and parliamentary records. The time scale of such transitions driven by aroused public opinion is typically a decade. Actors are primary producers (farmers), other supply chain parties, authorities, NGOs voicing particular opinions, political parties, and consumers. Their interactions and reactions to external events are modelled in an agent-based simulation. The purposes of the simulation are (1) to validate that hypothetical relations derived from the dramaturgical analysis indeed lead to the emergence of the observed transitions, and (2) to study how the system could have developed under different behaviours or a different course of external events. Simulation results and a sensitivity analysis are discussed. The simulation shows particularly sensitive for the participation of both moderate and activist NGOs.
    Luisteren naar consument en keten: Result-sheet van Tuinbouw Digitaal-project in PPS ‘a SMARTER Greenport’
    Schmeitz, H. ; Verwaart, T. - \ 2014
    Wageningen : LEI Wageningen UR
    Agent-based modelling and simulation for agricultural policy
    Verwaart, Tim - \ 2014
    Agent-based modelling and simulation
    Verwaart, Tim - \ 2014
    Evaluating Scenarios for Upgrading Sustainability of the Meat Supply Chain
    Broek, E.M.F. van den; Verwaart, T. - \ 2014
    In: Advances in Artificial Economics / Amblard, F., Miguel, F.J., Blanchet, A., Benoit, G., Heidelberg : Springer (Lecture Notes in Economics and Mathematical Systems 676) - ISBN 9783319095776
    Dutch Open Data on Agriculture: Policy, Practice, Pilot applications
    Verwaart, Tim - \ 2014
    Comparing two sensitivity analysis approaches for two scenarios with a spatially explicit rural agent-based model
    Schouten, M.A.H. ; Verwaart, T. ; Heijman, W.J.M. - \ 2014
    Environmental Modelling & Software 54 (2014)April. - ISSN 1364-8152 - p. 196 - 210.
    land-use - environmental-models - agricultural policies - simulation - biodiversity - schemes - uncertainty - landscapes - management - protocol
    In this paper two sensitivity analysis approaches are applied for scenario analysis in a spatially explicit rural agent-based simulation. The simulation aims to assess the socioeconomic and ecological impacts of agricultural policy interventions, market dynamics and environmental change on a regional scale. Two different methods of sensitivity analysis are investigated: i) a one-at-a-time approach where each parameter is varied one after the other, while all other parameters are kept at their nominal values; and ii) a procedure based on Monte Carlo sampling where random sets of input parameter values are related to outputs of the simulation. The complementarity of both approaches and their contribution to the overall interpretation of the model is shown in two scenarios simulating alternative European policy instruments for biodiversity conservation. Results show that a mixed approach of sensitivity analysis leads to a better understanding of the model’s behaviour, and further enhances the description of the simulation’s response to changes in inputs and parameter settings.
    Cross-validation of Gaming Simulation and Multi-agent Simulation
    Hofstede, G.J. ; Jonker, C.M. ; Verwaart, T. - \ 2014
    In: Perspectives on Culture and Agent-based Simulations / Dignum, V., Dignum, F., Dordrecht : Springer Science+Business Media (Studies in the Philosophy of Sociality 3) - ISBN 9783319019512 - 323 p.
    Information and Communication Technology as a Driver for Change in Agri-food Chains
    Poppe, Krijn J. ; Wolfert, J. ; Verdouw, Cor ; Verwaart, Tim - \ 2013
    EuroChoices 12 (2013)1. - ISSN 1478-0917 - p. 60 - 65.
    Agri-food chains will be changed in the coming years by Information and Communication Technology (ICT). Technological trends and economic analysis suggest that ICT will be a major driver for innovation. Satellites and sensors make precision agriculture possible. More and more data are being generated in agriculture and the rest of the food chain, which helps to steer production processes with greater precision. However, there is a low level of integration of these data between actors in the food chain. By improving this ‘interoperability’ of data, processes in the food chain can be optimised and new business models developed. Data-intensive food chains have the potential to alleviate many of the current sustainability and food safety issues and contribute to human health. The economic and policy effects of such developments still need to be explored. At first sight it could lead to more closely integrated supply chains that make the farmer act as a franchise taker with limited freedom. But the opposite could also be true, with more transparency and easier options for direct sales via consumer food webs, using smart solutions for the ‘last mile’ delivery. New issues like a trade-off between transparency and privacy or pricing data might well arise.
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