其他摘要 | Prospect theory (PT) and cumulative prospect theory (CPT) have revealed a sophisticated preference pattern among individuals that goes beyond the "twofold" pattern of risk-taking for gains and risk aversion for losses, as exemplified by buying lotteries and buying insurances. Instead, individuals exhibit a "fourfold pattern" preference that encompasses risk-taking and risk averse, respectively, of gains and losses for small probability; risk averse and risk-taking, respectively, of gains and losses for large probability, as termed by KT's "fourfold pattern" preference. CPT offers an account for this preference pattern by positing an overweighting of small probabilities in the weighting function, yet this proposition is directly challenged and
reshaped by Markowitz's "fourfold pattern" preference.
The two distinct versions of the "fourfold pattern" preferences have prompted a thorough reevaluation of the underlying decision-making mechanisms. Furthermore, the incapacity of CPT to explain both versions of "fourfold pattern" has motivated researchers to contemplate the possibility of abandoning alternative-based assumption (weighting and adding process), and instead embracing a dimension-based (non-compensatory) decision model for mechanism interpretation.
As one of the representative models of non-compensatory decision-making, equate-to-differentiate (ETD) model can theoretically explain the two distinct versions of the "fourfold pattern" preferences based solely on the perceived difference between the two options on the "best-possible-outcome" and "worst-possible-outcome". Therefore, a key scientific question in this doctoral dissertation is whether the "fourfold pattern" preferences in risky choice can be explained by ETD model. Is it better to explain them using a dimension-based/non-compensatory decision model or an alternative-based/compensatory decision model?
Study 1 aims to investigate whether the two distinct versions of the "fourfold pattern" preferences in risky choice can be explained by ETD model. Two sub一studies were designed to examine whether ETD model can account the two versions of the "fourfold pattern" preferences identified by KT (Sub-study 1.1) and Markowitz (Sub-study 1.2), respectively. Visual analog scales were utilized to measure the mediators, and mediation analyses were conducted. The findings indicate that, even if individuals' preference patterns did not entirely demonstrate the full "fourfold pattern" predicted by CPT, the observed preference patterns could be explained by ETD model, providing preliminary behavioral evidence for ETD model's explanation of the "fourfold pattern" preferences in risky choice.
Study 2 builds on the foundation laid by the Study 1 and investigates whether people's preference patterns under different ambiguous formats are consistent with those in risky choice. The theoretical rationale for this study is to test ETD model under more stringent condition (falsifiable) but also more lenient conditions for a model of "weighting and adding". Specifically, it is not a requirement that 1) the functions of Markowitz or KT in current format possess the capacity to accurately convert ambiguous probabilities or outcomes into precise "weighting" or "value", and 2) the prospects of the ambiguous options calculated via "weighting and adding" conform to the relationship corresponding to the "fourfold pattern" preference. However, ETD model suggests that individuals' preference patterns under ambiguous conditions should exhibit a consistent pattern as in risky choice as long as the differences between the two options on the "best-possible-outcome" dimension and the "worst-possible-outcome" dimension proportionally remain the same as "fourfold pattern" under risky conditions. The study comprises three experimental conditions: ambiguous probabilities (Sub-study 2.1.1), ambiguous outcomes (Sub-study 2.1.2), and full ambiguity for both probabilities and outcomes (Sub-study 2.2). In each condition, the corresponding information is presented in both verbal and numerical formats to verify whether the "fourfold pattern" preferences proposed by KT and Markowitz can be replicated. The results demonstrate that both KT's and Markowitz's "fourfold pattern" preference models can be detected or observed in most cases, providing supportive evidence for the ETD model's ability to explain the "fourfold pattern" preferences in decision-making under fuzziness.
The main purpose of Study 3 is to provide intuitive eye-movement process evidence for the explanatory mechanism of the "fourfold pattern" preferences. To this end, Study 3 constructs 16 sets of parameters for the "fourfold pattern" under both risky and ambiguous probability conditions in a pre-experiment, and uses a "probability-proportion" paradigm in the formal experiment, with a calculation rule-based proportion task of "XX% of XX Yuan" as the baseline. By comparing the eye-movement characteristics between risky and ambiguous choices, as well as between probability and proportion tasks, the results reveal that the information search process of ambiguous choices is more likely being dimension-based than risky choices; the information search process of probability tasks is more likely being dimension-based than proportion tasks, and the eye-tracking indicators of the ETD model can fit the choice results when people make free choices. This study provides direct and strong process evidence for the ETD model's explanation of the "fourfold pattern" preference model.
Study 4 attempts to apply the ETD model to intertemporal and spatial choices and explore whether similar intertemporal and spatial versions of the "fourfold pattern" preferences could be generated. The results indicated that, in both intertemporal and spatial choices, participants' preference patterns exhibited intertemporal and spatial versions of the KT's "fourfold pattern" preference, which is similar to the KT's "fourfold" pattern under risk.
This doctoral dissertation examines mechanism underlying both two versions of "fourfold pattern" preferences in risky choices and provides a coherent explanation of the "fourfold pattern" preferences using ETD model. Furthermore, following the "intra-dimensional comparison" approach, we generated similar "fourfold pattern" preference in intertemporal and spatial choices, akin to the KT's "fourfold pattern" preference under risk. It therefore not only brings new and unprecedented challenges to the "alternative-based and compensatory" intertemporal/spatial choice model but also made exploratory attempts to deepen the understanding of decision-making mechanisms in risky, intertemporal and spatial choices and to explain people's real economic behavior. |
修改评论