The threefold purpose of this initial chapter is to provide a review of the historical origins and the methodological beauty of sampling approaches to judgment and decision-making, to illuminate the most prominent recent developments, and to provide a preview of all chapters included in this volume. Accordingly, the chapter is organized into three parts. The historical review in the first part highlights the progress from purely intra-psychic to cognitive-ecological perspectives on adaptive cognition, conceived as a genuine interaction between environmental constraints and adaptive agents’ sampling strategies. The review of novel trends in the second part testifies to the fertility of sampling approaches and the impressive amount of progress it has inspired in terms of functional-level applications in various areas, but also in terms of mechanistic and computational modeling. A preview of all 22 chapters of the present volume in the final part is organized into six sections, covering the full spectrum of these innovative developments in rationality research during the last 15 years.

Information amount is a crucial determinant of decision outcomes. But how much information one should collect before arriving at a decision depends on a cost–benefit trade-off: Is the expected benefit of increased decision accuracy that can be gained from additional information higher than the additional information costs? To investigate this trade-off with temporal costs for information, we developed a speed–accuracy trade-off paradigm with sample-based decisions, in which the total payoff was the product of the average payoff per decision and the number of decisions completed in a restricted period. Increasing n served to increase the accuracy of choices, but also to decrease the number of completed choices. Yet, whereas the number of completed choices decreases linearly with increasing n, accuracy increases in a clearly sublinear fashion. As a consequence, the sample-based choice task calls for more weight given to speed than to accuracy. However, overly conservative sampling strategies prevented almost all participants from exploiting the speed advantage despite various guiding interventions. Even when the task was enriched by the social aspect of a teammate or rival, who demonstrated the optimal trade-off, participants remained too focussed on accuracy. We also investigate the cost–benefit trade-off with financial information costs, for which participants’ performance was less biased. We propose this to be related to how evaluable the information’s costs were relative to its benefits. Issues of adaptivity in contrast with optimality are addressed in a final discussion.

To understand and explain sample-based impression formation, it is necessary to consider both the Brunswikian uncertainty caused by sampling from the stimulus environment and the Thurstonian uncertainty arising from the cognitive processing thereof. Impression judgments must be formed in view of both sources of uncertainty. Even when an ecological sample of a target’s traits is held constant, the resulting distribution of target information in the judge’s mind can vary substantively as a function of semantic and affective responses, top-down inferences, and contextual influences. In the research reviewed in the present chapter, we investigate the interplay of Brunswikian and Thurstonian sampling in a person-impression task based on self-truncated trait samples, in which judges can stop sampling at the very moment when their internal mindset optimally prepares them to form a distinct impression. This task setting produces distinct self-truncation effects; the resulting impression judgments are polarized, conflict-free, and typically driven by small samples (after early truncation). When exactly the same traits are presented in a yoked-control design to other judges, who cannot exploit self-truncation effects, their judgment patterns are similar but clearly less pronounced, reflecting the same Brunswikian trait samples detached from the Thurstonian mindset.

Peer review supports decisions related to publications, grant proposals, awards, or personnel selection. Independent of the specific occasion, we propose validity as a chief evaluation criterion for reviews. While applicable to all occasions, the principles of validity-oriented quality control are particularly suited for journal reviews. Beyond evaluating validity and the scientific potential of a given piece of research, we address how peer reviewing serves important functions and is accountable for the growth of science at a more superordinate level. We also provide guidelines and concrete recommendations for how a good peer review may serve these functions. Good peer review, thereby, fosters both the advancement of scientific research and the quality, precision, and sincerity of the scientific literature. The end of the chapter is devoted to a core set of good reviewer practices, conceived as an essential feature of academic culture.