Substitution of food products will be key to realising widespread adoption of sustainable diets. We present an agent-based model of decision-making and influences on food choice, and apply it to historically observed trends of British whole and skimmed (including semi) milk consumption from 1974 to 2005. We aim to give a plausible representation of milk choice substitution, and test di erent mechanisms of choice consideration. Agents are consumers that perceive information regarding the two milk choices, and hold values that inform their position on the health and environmental impact of those choices. Habit, social influence and post-decision evaluation are modelled. Representative survey data on human values and long-running public concerns empirically inform the model. An experiment was run to compare two model variants by how they perform in reproducing these trends. This was measured by recording mean weekly milk consumption per person. The variants di ered in how agents became disposed to consider alternative milk choices. One followed a threshold approach, the otherwas probability based. All othermodel aspects remained unchanged. An optimisation exercise via an evolutionary algorithmwas used to calibrate themodel variants independently to observed data. Following calibration, uncertainty and global variance-based temporal sensitivity analysis were conducted. Both model variants were able to reproduce the general pattern of historical milk consumption, however, the probability-based approach gave a closer fit to the observed data, but over a wider range of uncertainty. This responds to, and further highlights, the need for research that looks at, and compares, di erent models of human decision-making in agent-based and simulationmodels. This study is the first to present an agent-based modelling of food choice substitution in the context of British milk consumption. It can serve as a valuable pre-curser to the modelling of dietary shi and sustainable product substitution to plant-based alternatives in Britain.

中文翻译：

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比较英国基于代理的牛奶消费和替代模型中的食物选择机制

食品替代品将是实现可持续饮食广泛采用的关键。我们提出了一个基于代理的决策模型和对食物选择的影响，并将其应用于从 1974 年到 2005 年英国全脂和脱脂（包括半）牛奶消费的历史观察趋势。我们的目标是给出牛奶选择的合理表示替代，并测试不同的选择考虑机制。代理人是消费者，他们感知有关两种牛奶选择的信息，并持有表明他们对这些选择对健康和环境影响的立场的价值观。习惯、社会影响和决策后评估被建模。关于人类价值观和长期公众关注的代表性调查数据从经验上为模型提供了信息。进行了一项实验，通过它们在再现这些趋势方面的表现来比较两个模型变体。这是通过记录每人每周平均牛奶消耗量来衡量的。这些变体在代理商如何倾向于考虑替代牛奶选择方面有所不同。一种遵循阈值方法，另一种是基于概率的方法。所有其他模型方面保持不变。通过进化算法的优化练习被用来独立于观察到的数据校准模型变体。在校准之后，进行了基于不确定性和全局方差的时间敏感性分析。两种模型变体都能够重现历史牛奶消费的一般模式，但是，基于概率的方法更接近于观察到的数据，但不确定性范围更广。这回应，并进一步强调，需要研究并比较基于代理和模拟模型中人类决策的不同模型。这项研究首次提出了在英国牛奶消费背景下基于代理的食物选择替代模型。它可以作为英国膳食营养模型和可持续产品替代植物替代品的有价值的先驱。