Volume 6, Issue 3

The identification of experts is crucial in many research projects and domain application areas. However, research reports often assert that the research participants were experts, when in fact the participants were graduate students, or individuals having only a few years of professional experience. This essay briefly discusses the conceptual definition of expertise, and questions the tendency of researchers to bifurcate humanity into novices versus experts. The essay then addresses the matter of how to identify experts, offering a method that is more robust and scientifically grounded than the common, and questionable reliance on the so-called “10-year” or "10,000 hours" rules for deciding who is, and who is not an expert. The approach presented here is based on five distinct classes of methods. The Pentapod Principle asserts that rigorous proficiency scaling should rely on methods from at least three of the classes. This approach should be useful in any investigation that intends to study experts and present conclusions about expertise.

This article contributes to our understanding of teachers’ visual expertise by measuring visual information processing in real-world classrooms (mobile eye-tracking) with the newly introduced Gaze Relational Index (GRI) metric, which is defined as the ratio of mean fixation duration to mean fixation number. In addition, the aim of this article was to provide a methodological contribution to future research by showing the extent to which the selected configurations (i.e., varying velocity thresholds and fixation merging) of the eye-movement-event-detection algorithm for detecting fixations and saccades influence the results of eye-tracking studies. Our study has two important take-home messages: First, by adopting a novice-expert paradigm (two novice teachers and two experienced teachers), we found that the GRI can serve as a sensitive measure of visual expertise. As hypothesized, experienced teachers’ GRI was lower than that of the novice teachers, suggesting that their more fine-graded organization of domain-specific knowledge allows them to fixate more rapidly and frequently in the classroom. Second, we found that the selected velocity threshold parameter alters and, in the worst-case scenario, biases the results of an eye-tracking study. Therefore, in the interest of the further generalizability of the results within visual-expertise research, we emphasize that it is highly important to report configurations that are relevant to the identification of eye movements.

Expert opinion evidence is ubiquitous in civil and criminal justice procedures. Its use is longstanding, widespread, and influential. However, non-expert factfinders have been criticized for their ineffective management of improper and unvalidated forensic science evidence. Some argue this mishandling arises from the epistemic incompetence of judges and juries. In this paper we use screenwriter Dale Launer’s persuasive expert character Mona Lisa Vito from the 1992 film My Cousin Vinny to explore the epistemic (in)competence of non-expert evaluators. When placed in the context of expert persuasion scholarship, this analysis reveals strengths and weaknesses of non-expert evaluations of expert witnesses. In particular, there are issues relating to the foundation of expert opinions, the certainty of expert conclusions, and tendency to stray outside one’s area of expertise. These matters are examined as potential targets for interventions to improve the reception and handling of expert opinion evidence, as well as the fairness and rectitude of criminal justice procedures.

In 2019, we published a paper in the Journal of Expertise (Ventura et al., 2019) showing that visual words show holistic processing, deemed a characteristic of faces, when the visual stimuli are within the limits of expertise of the Visual Word Form System (Cohen et al., 2008) and thus when there is fast parallel reading. In this commentary, we discuss this evidence considering the perspective of shared processing across both faces and words vs. the perspective of domain specificity for the processing of each domain. Considering the most recent evidence of mutual interference of holistic processing of words and faces (Ventura et al., 2023), we conclude for the first perspective; i.e., shared processing across both faces and words.