Deliberately vague or vaguely deliberative: A review of motivation and design choices in deliberative monetary valuation studies

Deliberative Monetary Valuation (DMV) was developed in response to critique on traditional stated preference methods and combines elements of deliberative institutions with the elicitation of monetary values. In the theoretical DMV literature, two strands based on different motivations for employing deliberation were identified: preference economization studies, where the goal is to help participants form informed and stable individual preferences; and preference moralization studies, where deliberation is meant to help uncover preferences that transcend individual interests and take into account a broader set of values. The common assumption is that these different motivations are reflected in distinct study design choices. However, this assumption has not been systematically verified. We present a review of the empirical DMV literature in which we systematically identify and assess the design choices made in DMV studies to verify whether the different motivations translate into different patterns in study design. We find some trends, but also a large heterogeneity within each category. The study designs seem to mainly reflect the particular focus of each study. We argue that this is linked to the lack of agreed-upon standards for DMV studies. Our review demonstrates the need for an empirically verified framework that associates motivations for deliberation with study design choices.