Null hypothesis significance testing uses the seemingly arbitrary probability of .05 as a means of objectively determining whether a tested effect is reliable. Within recent psychological articles, research has found an overrepresentation of p values around this cut-off. The present study examined whether this overrepresentation is a product of recent pressure to publish or whether it has existed throughout psychological research. Articles published in 1965 and 2005 from two prominent psychology journals were examined. Like previous research, the frequency of p values at and just below .05 was greater than expected compared to p frequencies in other ranges. While this overrepresentation was found for values published in both 1965 and 2005, it was much greater in 2005. Additionally, p values close to but over .05 were more likely to be rounded down to, or incorrectly reported as, significant in 2005 than in 1965. Modern statistical software and an increased pressure to publish may explain this pattern. The problem may be alleviated by reduced reliance on p values and increased reporting of confidence intervals and effect sizes.

Approach motivation leads to greater left hemisphere activation, whereas an avoidant motivational state activates the right hemisphere. Recent research, which served as the basis for the current experiment, suggests line bisection provides a simple measure of approach/avoidance lateralisation. Findings from Experiment 1 indicated that the landmark task was sensitive enough to identify lateral asymmetries evoked by happy and angry faces; however, follow-up experiments failed to replicate this finding. When task instructions were slightly modified or when a mixed design was used, motivation did not influence landmark task performance. The use of images in lieu of faces also failed to produce a significant effect. Importantly, a straight replication of Experiment 1 produced a null result. Line bisection does not appear to be a suitable measure of lateralised approach/avoidance biases, possibly due to the high individual variability inherent in visuospatial biases. Implications for null hypothesis significance testing are also discussed.

Gaze linking allows team members in a collaborative visual task to scan separate computer monitors simultaneously while their eye movements are tracked and projected onto each other’s displays. The present study explored the benefits of gaze linking to performance in unguided and guided visual search tasks. Participants completed either an unguided or guided serial search task as both independent and gaze-linked searchers. Although it produced shorter mean response times than independent search, gaze linked search was highly inefficient, and gaze linking did not differentially affect performance in guided and unguided groups. Results suggest that gaze linking is likely to be of little value in improving applied visual search.

Objective The aim was to test the value of shared gaze as a way to improve team performance in a visual monitoring task. Background Teams outperform individuals in monitoring tasks, but fall short of achievable levels. Shared-gaze displays offer a potential method of improving team efficiency. Within a shared-gaze arrangement, operators collaborate on a visual task, and each team member’s display includes a cursor to represent the other teammates’ point of regard. Past work has suggested that shared gaze allows operators to better communicate and coordinate their attentional scanning in a visual search task. The current experiments sought to replicate and extend earlier findings of inefficient team performance in a visual monitoring task, and asked whether shared gaze would improve team efficiency. Method Participants performed a visual monitoring task framed as a sonar operation. Displays were matrices of luminance patches varying in intensity. The participants’ task was to monitor for occasional critical signals, patches of high luminance. In Experiment 1, pairs of participants performed the task independently, or working as teams. In Experiment 2, teams of two participants performed the task with or without shared-gaze displays. Results In Experiment 1, teams detected more critical signals than individuals, but were statistically inefficient; detection rates were lower than predicted by a control model that assumed pairs of operators searching in isolation. In Experiment 2, shared gaze failed to increase target detection rates. Conclusion and application Operators collaborate inefficiently in visual monitoring tasks, and shared gaze does not improve their performance.

Two-person teams outperform individuals in search tasks, and even exceed expectations based on statistical limitations. Here, we aimed to replicate and extend this result. We used Bayesian hierarchical modelling of receiver operating characteristics to examine collaborative performance in a visual search task wherein top-down target information was constrained. Participants (N = 16 teams per experiment in Experiments 1 and 2; N = 24 teams in Experiment 3), working independently or collaboratively, performed a search task framed as a medical image reading task. Stimuli were polygons generated by randomly distorting a prototype shape. Observers judged whether an extreme distortion was present among a set of low-distortion distractor objects. Team members' individual sensitivity levels were used to predict collaborative sensitivity using two versions of a uniform judgment-weighting (UW) model, one that assumed stochastically independent judgments and one that accounted for correlations in the team members' judgments. Collaborative search was better than that from single observers in all three experiments, and consistently trended higher than predictions of the correlated UW model. Results imply that collaborative search can be highly efficient even when target foreknowledge is limited.

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