The decoy effect reveals a potential violation of the regularity assumption, which is a building block of canonical discrete choice models. This effect has been detected in various choice contexts, but the susceptibility to it and its subjective valuation have been scarcely studied before. This paper proposes, illustrates and assesses two methodologies aimed to fill this gap: systematic taste variations and latent classes. The first approach uses a logit model that accounts for the decoy effect by an emergent value term which coefficient varies among groups of individuals defined by exogenous variables. The second method uses a similar scheme but accounts for heterogeneity, instead, by using three variations of the latent classes approach. This article illustrates and assesses the proposed methods using a case study build from a stated preferences route choice problem that depicts a hypothetical Saturday afternoon car shopping trip. Results show first that both methods are feasible for analyzing the decoy effect and that only respondent's age and response time seem to play a clear role in decoy's susceptibility in the case study. On the contrary, no noticeable impact on susceptibility is detected for gender, imputed income, motorization rate, household size and whether the survey was conducted in person or online. Finally, regarding decoy's subjective valuation, evidence from this case study suggests that presenting the decoy was, on average, as large as reducing about one fourth of the travel time, or between one fourth and one half of the travel cost displayed to the interviewees.

诱饵效应表明有可能违反正则性假设，这是规范离散选择模型的基础。已经在各种选择环境中检测到了这种影响，但是以前很少研究其敏感性和主观评价。本文提出，说明和评估了旨在填补这一空白的两种方法：系统的口味变化和潜在类别。第一种方法使用logit模型，该模型通过紧急值项解释诱骗效果，该紧急值项的系数在由外源变量定义的个体组之间变化。第二种方法使用类似的方案，但考虑到了异构性，而是使用了潜在类方法的三种变体。本文使用一个案例研究来说明和评估所提出的方法，该案例是根据描述了一个假设的周六下午购车旅行的陈述的偏好路线选择问题构建的。结果首先表明，两种方法都可用于分析诱饵效果，并且在案例研究中，只有受访者的年龄和响应时间似乎对诱饵的易感性起明显作用。相反，在性别，估算收入，机动化率，家庭人数以及该调查是亲自还是在线进行的调查中，均未发现对药敏性有明显影响。最后，关于诱饵的主观评估，本案例研究的证据表明，展示诱饵的平均时间大约可减少旅行时间的四分之一，