The notion of hypothetical bias (HB) constitutes, arguably, the most fundamental issue in relation to the use of hypothetical survey methods. Whether or to what extent choices of survey participants and subsequent inferred estimates translate to real-world settings continues to be debated. While HB has been extensively studied in the broader context of contingent valuation, it is much less understood in relation to choice experiments (CE). While the number of CE studies has rapidly increased, the critical issue of HB has been studied in only a small fraction of CE studies. This paper provides macro-scale insights into the literature of CE and reviews the empirical evidence for HB in CE in various fields of applied economics as well as experimental psychology and behavioural neuroscience. Results suggest mixed evidence on the prevalence, extent and direction of HB as well as considerable context and measurement dependency. While HB is found to be an undeniable issue when conducting CEs, the empirical evidence on HB does not render CEs unable to represent real-world preferences. While health-related choice experiments often find negligible degrees of HB, experiments in consumer behaviour and transport domains suggest significant degrees of HB. Environmental valuation studies provide mixed evidence. Also, across these disciplines many studies display HB in their total willingness to pay estimates and opt-in rates but not in their hypothetical marginal rates of substitution (subject to scale correction). Further, recent findings in psychology and brain imaging studies identify neurocognitive mechanisms underlying HB that may explain some of the discrepancies and unexpected findings in the mainstream CE literature.

假设偏差的概念(HB) 可以说是与使用假设调查方法相关的最基本问题。调查参与者的选择和随后的推断估计是否或在多大程度上转化为现实世界的设置，仍然存在争议。虽然 HB 已在条件估值的更广泛背景下进行了广泛研究，但与选择实验 (CE) 相关的理解却少得多。虽然 CE 研究的数量迅速增加，但只有一小部分 CE 研究研究了 HB 的关键问题。本文提供了对 CE 文献的宏观见解，并回顾了 CE 中 HB 在应用经济学以及实验心理学和行为神经科学的各个领域中的经验证据。结果表明流行的混合证据，HB 的范围和方向以及相当大的上下文和测量依赖性。虽然在进行 CE 时发现 HB 是一个不可否认的问题，但关于 HB 的经验证据并未使 CE 无法代表现实世界的偏好。虽然与健康相关的选择实验通常发现 HB 的程度可以忽略不计，但消费者行为和交通领域的实验表明 HB 的程度很高。环境评估研究提供了混合证据。此外，在这些学科中，许多研究在他们的总体支付意愿和选择率方面显示了 HB，但在他们假设的边际替代率（取决于比例修正）方面没有显示。更远，