Minimum aberration designs for discrete choice experiments

A discrete choice experiment (DCE) is a survey method that givesinsight into individual preferences for particular attributes.Traditionally, methods for constructing DCEs focus on identifyingthe individual effect of each attribute (a main effect). However, aninteraction effect between two attributes (a two-factor interaction)better represents real-life trade-offs, and provides us a better understandingof subjects’ competing preferences. In practice it is oftenunknown which two-factor interactions are significant. To address theuncertainty, we propose the use of minimum aberration blockeddesigns to construct DCEs. Such designs maximize the number ofmodels with estimable two-factor interactions in a DCE with two-levelattributes. We further extend the minimum aberration criteria toDCEs with mixed-level attributes and develop some general theoreticalresults

Delayed-choice gedanken experiments and their realizations

The wave-particle duality dates back to Einstein's explanation of the photoelectric effect through quanta of light and de Broglie's hypothesis of matter waves. Quantum mechanics uses an abstract description for the behavior of physical systems such as photons, electrons, or atoms. Whether quantum predictions for single systems in an interferometric experiment allow an intuitive understanding in terms of the particle or wave picture, depends on the specific configuration which is being used. In principle, this leaves open the possibility that quantum systems always either behave definitely as a particle or definitely as a wave in every experimental run by a priori adapting to the specific experimental situation. This is precisely what is tried to be excluded by delayed-choice experiments, in which the observer chooses to reveal the particle or wave character -- or even a continuous transformation between the two -- of a quantum system at a late stage of the experiment. We review the history of delayed-choice gedanken experiments, which can be traced back to the early days of quantum mechanics. Then we discuss their experimental realizations, in particular Wheeler's delayed choice in interferometric setups as well as delayed-choice quantum erasure and entanglement swapping. The latter is particularly interesting, because it elevates the wave-particle duality of a single quantum system to an entanglement-separability duality of multiple systems

Choice set awareness and ordering effects in discrete choice experiments in discrete choice experiments

The choice experiment elicitation format confronts survey respondents with repeated choice tasks. Particularly within the context of valuing pure public goods, this repetition raises two issues. First, does advanced awareness of multiple tasks influence stated preferences from the outset, and second, even in the absence of such awareness, does the process of working through a series of choice tasks influence stated preferences leading to choice outcomes that are dependent on the order in which a question is answered? The possible motivators of these effects include economic-theoretic reasons such as strategic behavior, as well as behavioral explanations such as response heuristics and learning effects. A case study of a familiar good (drinking water quality) combines a split sample treatment of the presence/absence of advanced awareness with a full factorial design permitting systematic variation of the order in which choices are presented to respondents. A further sample division allows examination of effects arising from variation in the scope of the initial good presented to respondents. Using discrete choice panel data estimators we show that both advanced awareness and order effects exist alongside interactions with the scope of the initial good

HYPOTHETICAL (NON)BIAS IN CHOICE EXPERIMENTS: EVIDENCE FROM FRESHWATER PRAWNS

A mail survey choice experiment and in-store controlled experiment were conducted concurrently in the same location to test for hypothetical bias in choice experiments using a new product—freshwater prawns. Findings suggest that hypothetical bias in the mail survey was not present for the new product, but some hypothetical bias was detected for substitute products, depending on the choice of econometric estimation method. However, the general conclusion is the choice experiments are an effective means of assessing potential market demand for new products with little evidence for hypothetical bias.hypothetical bias, choice experiments, in-store experiments, functional form choice

The Role of Choice in Social Dilemma Experiments

On the basis of problems related to asymmetric information, self-governance has been proposed and often empirically found to be superior to the external imposition of rules in social dilemma situations. The present paper suggests and experimentally analyses a different line of argument, namely to what extent behavioral aspects can explain these findings. We study this hypothesis using the simplest, most general dilemma form: the prisoner's dilemma (PD). We compare behavior when players are given the possibility of choosing between two different representations of the same PD, to behavior when players are externally assigned to play a specific game. We find that cooperation rates are significantly higher in the games that were chosen.Freedom of Choice, Self-governance, Social Dilemmas, Framing

Why the Linear Utility Function is a Risky Choice in Discrete-Choice Experiments

This article assesses how the form of the utility function in discrete-choice experiments (DCEs) affects estimates of willingness-to-pay (WTP). The utility function is usually assumed to be linear in its attributes. Non-linearities, in the guise of interactions and higher-order terms, are applied only rather ad hoc. This paper sheds some light on this issue by showing that the linear utility function can be a risky choice in DCEs. For this purpose, a DCE conducted in Switzerland to assess preferences for statutory social health insurance is estimated in two ways: first, using a linear utility function; and second, using a non-linear utility function specified according to model specification rules from the econometrics and statistics literature. The results show that not only does the non-linear function outperform the linear specification with regard to goodness-of-fit, but it also generates significantly different WTP. Hence, the functional form of the utility function may have significant impact on estimated WTP. In order to produce unbiased estimates of preferences and to make adequate decisions based on DCEs, the form of the utility function should become more prominent in future experiments.Discrete-Choice Experiment, Preference Measurement, Health Insurance, Model Specification

The Impact of Protest Responses in Choice Experiments

Not much attention has been given to protest responses in choice experiments (CE). Using follow-up statements, we are able to identify protest responses and compute welfare estimates with and without the inclusion of such protest responses. We conclude that protest responses are fairly common in CE, and their analysis affects the statistical performance of the empirical models. In particular, when the sample is corrected by protests, our results come from utility consistent models. Thus, future choice experiments should consider the role of protest responses as contingent valuation studies have done.Protest Responses, Choice Experiments

Effects of alternative elicitation formats in discrete choice experiments

An elicitation format prevalently applied in DCE is to offer each respondent a sequence of choice tasks containing more than two choice options. However, empirical evidence indicates that repeated choice tasks influence choice behavior through institutional learning, fatigue, value learning, and strategic response. The study reported in this paper employs a split sample approach based on field surveys using a single binary elicitation format with a majority vote implementation as the baseline to expand the research on effects of sequential binary DCE formats. We provide evidence for effects caused by institutional learning and either strategic behavior or value learning after respondents answered repeated choice questions. However, we did not find any indications for strategic behavior caused by awareness of having multiple choices. The choice between a sequential and a single elicitation format may thus imply a trade-off between decreased choice accuracy and potentially increased strategic behavior due to an incentive incompatible mechanism. Further research is needed to explore strategic behavior induced by incentive incompatible elicitation formats using alternative approaches that are not compromised by a confounded baseline, that facilitate the differentiation between value learning and strategic behavior, and that allow the use of less restrictive model specifications. Such research should also investigate the effects of varying incentives induced by the order in which choice questions are presented to respondents.discrete choice experiments, split sample approach, elicitation format, incentive compatibility, strategic behavior, learning effects, panel mixed logit models, Environmental Economics and Policy,