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Smith et al. (2019) found standing resulted in better performance than sitting in three different cognitive control paradigms: a Stroop task, a task-switching, and a visual search paradigm. Here, we conducted close replications of the authors' three experiments using larger sample sizes than the original work. Our sample sizes had essentially perfect power to detect the key postural effects reported by Smith et al. The results from our experiments revealed that, in contrast to Smith et al., the postural interactions were quite limited in magnitude in addition to being only a fraction of the size of the original effects. Moreover, our results from Experiment 1 are consistent with two recent replications (Caron et al., 2020; Straub et al., 2022), which reported no meaningful influences of posture on the Stroop effect. In all, the current research provides further converging evidence that postural influences on cognition do not appear to be as robust, as was initially reported in prior work.

We describe a web and standalone Shiny app for calculating the common, linear within-individual association for repeated assessments of paired measures with multiple individuals: repeated measures correlation (rmcorr). This tool makes rmcorr more widely accessible, providing a graphical interface for performing and visualizing the output of analysis with rmcorr. In contrast to rmcorr, most widely used correlation techniques assume paired data are independent. Incorrectly analyzing repeated measures data as independent will likely produce misleading results. Using aggregation or separate models to address the issue of independence may obscure meaningful patterns and will also tend to reduce statistical power. rmcorrShiny (repeated measures correlation Shiny) provides a simple and accessible solution for computing the repeated measures correlation. It is available at: https://lmarusich.shinyapps.io/shiny_rmcorr/., Competing Interests: No competing interests were disclosed., (Copyright: © 2021 Marusich LR and Bakdash JZ.)

We describe a web and standalone Shiny app for calculating the common, linear within-individual association for repeated assessments of paired measures with multiple individuals: repeated measures correlation (rmcorr). This tool makes rmcorr more widely accessible, providing a graphical interface for performing and visualizing the output of analysis with rmcorr. In contrast to rmcorr, most widely used correlation techniques assume paired data are independent. Incorrectly analyzing repeated measures data as independent will likely produce misleading results. Using aggregation or separate models to address the issue of independence may obscure meaningful patterns and will also tend to reduce statistical power. rmcorrShiny (repeated measures correlation Shiny) provides a simple and accessible solution for computing the repeated measures correlation. It is available at: https://lmarusich.shinyapps.io/shiny_rmcorr/., Competing Interests: No competing interests were disclosed., (Copyright: © 2021 Marusich LR and Bakdash JZ.)

Whether in meta-analysis or single experiments, selecting results based on statistical significance leads to overestimated effect sizes, impeding falsification. We critique a quantitative synthesis that used significance to score and select previously published effects for situation awareness-performance associations (Endsley, 2019). How much does selection using statistical significance quantitatively impact results in a meta-analytic context? We evaluate and compare results using significance-filtered effects versus analyses with all effects as-reported. Endsley reported high predictiveness scores and large positive mean correlations but used atypical methods: the hypothesis was used to select papers and effects. Papers were assigned the maximum predictiveness scores if they contained at-least-one significant effect, yet most papers reported multiple effects, and the number of non-significant effects did not impact the score. Thus, the predictiveness score was rarely less than the maximum. In addition, only significant effects were included in Endsley's quantitative synthesis. Filtering excluded half of all reported effects, with guaranteed minimum effect sizes based on sample size. Results for filtered compared to as-reported effects clearly diverged. Compared to the mean of as-reported effects, the filtered mean was overestimated by 56%. Furthermore, 92% (or 222 out of 241) of the as-reported effects were below the mean of filtered effects. We conclude that outcome-dependent selection of effects is circular, predetermining results and running contrary to the purpose of meta-analysis. Instead of using significance to score and filter effects, meta-analyses should follow established research practices., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2020 Bakdash, Marusich, Kenworthy, Twedt and Zaroukian.)

Peer-to-peer lending is hypothesized to help equalize economic opportunities for the world's poor. We empirically investigate the "flat-world" hypothesis, the idea that globalization eventually leads to economic equality, using crowdfinancing data for over 660,000 loans in 220 nations and territories made between 2005 and 2013. Contrary to the flat-world hypothesis, we find that peer-to-peer lending networks are moving away from flatness. Furthermore, decreasing flatness is strongly associated with multiple variables: relatively stable patterns in the difference in the per capita GDP between borrowing and lending nations, ongoing migration flows from borrowing to lending nations worldwide, and the existence of a tie as a historic colonial. Our regression analysis also indicates a spatial preference in lending for geographically proximal borrowers. To estimate the robustness for these patterns for future changes, we construct a network of borrower and lending nations based on the observed data. Then, to perturb the network, we stochastically simulate policy and event shocks (e.g., erecting walls) or regulatory shocks (e.g., Brexit). The simulations project a drift towards rather than away from flatness. However, levels of flatness persist only for randomly distributed shocks. By contrast, loss of the top borrowing nations produces more flatness, not less, indicating how the welfare of the overall system is tied to a few distinctive and critical country-pair relationships.

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Objective: A human factors engineering-based intervention aimed at the modification of task behavior to increase adherence to best practices and the reduction of central line-associated bloodstream infections (CLABSI). The hypothesis was tested that a central line maintenance kit would improve adherence and reduce CLABSI compared with a standard, nonkit-based method of performing central line maintenance., Design: The study design was a 29-month prospective, interventional, nonrandomized, observational, and clinical research study using a pre-post implementation assessment., Setting: The study was conducted at a tertiary hospital in the southwestern United States, with participants recruited from a total of 6 patient units (including intensive care units and general wards)., Participants: A total of 95 nurses and 151 patients volunteered to participate in the study., Intervention: A central line maintenance kit was developed that incorporated human factors engineering design principles. This kit was implemented hospitalwide during the clinical study to assess the intervention's influence on protocol adherence and clinical outcomes compared with a preimplementation control condition (no kit use)., Results: The results of this clinical observations study suggest that a human factors engineering-based kit improved adherence to best practices during central line maintenance. In addition, the number of CLABSIs was significantly reduced during the postimplementation period., Conclusions: The application of human factors engineering design principles in the development of medical kits can improve protocol adherence and clinical outcomes., (Published by Elsevier Inc.)

Most risk analysis models systematically underestimate the probability and impact of catastrophic events (e.g., economic crises, natural disasters, and terrorism) by not taking into account interconnectivity and interdependence of risks. To address this weakness, we propose the Cascading Alternating Renewal Process (CARP) to forecast interconnected global risks. However, assessments of the model's prediction precision are limited by lack of sufficient ground truth data. Here, we establish prediction precision as a function of input data size by using alternative long ground truth data generated by simulations of the CARP model with known parameters. We illustrate the approach on a model of fires in artificial cities assembled from basic city blocks with diverse housing. The results confirm that parameter recovery variance exhibits power law decay as a function of the length of available ground truth data. Using CARP, we also demonstrate estimation using a disparate dataset that also has dependencies: real-world prediction precision for the global risk model based on the World Economic Forum Global Risk Report. We conclude that the CARP model is an efficient method for predicting catastrophic cascading events with potential applications to emerging local and global interconnected risks.

Repeated measures correlation (rmcorr) is a statistical technique for determining the common within-individual association for paired measures assessed on two or more occasions for multiple individuals. Simple regression/correlation is often applied to non-independent observations or aggregated data; this may produce biased, specious results due to violation of independence and/or differing patterns between-participants versus within-participants. Unlike simple regression/correlation, rmcorr does not violate the assumption of independence of observations. Also, rmcorr tends to have much greater statistical power because neither averaging nor aggregation is necessary for an intra-individual research question. Rmcorr estimates the common regression slope, the association shared among individuals. To make rmcorr accessible, we provide background information for its assumptions and equations, visualization, power, and tradeoffs with rmcorr compared to multilevel modeling. We introduce the R package (rmcorr) and demonstrate its use for inferential statistics and visualization with two example datasets. The examples are used to illustrate research questions at different levels of analysis, intra-individual, and inter-individual. Rmcorr is well-suited for research questions regarding the common linear association in paired repeated measures data. All results are fully reproducible.

Objective: We investigated how increases in task-relevant information affect human decision-making performance, situation awareness (SA), and trust in a simulated command-and-control (C2) environment., Background: Increased information is often associated with an improvement of SA and decision-making performance in networked organizations. However, previous research suggests that increasing information without considering the task relevance and the presentation can impair performance., Method: We used a simulated C2 task across two experiments. Experiment 1 varied the information volume provided to individual participants and measured the speed and accuracy of decision making for task performance. Experiment 2 varied information volume and information reliability provided to two participants acting in different roles and assessed decision-making performance, SA, and trust between the paired participants., Results: In both experiments, increased task-relevant information volume did not improve task performance. In Experiment 2, increased task-relevant information volume reduced self-reported SA and trust, and incorrect source reliability information led to poorer task performance and SA., Conclusion: These results indicate that increasing the volume of information, even when it is accurate and task relevant, is not necessarily beneficial to decision-making performance. Moreover, it may even be detrimental to SA and trust among team members., Application: Given the high volume of available and shared information and the safety-critical and time-sensitive nature of many decisions, these results have implications for training and system design in C2 domains. To avoid decrements to SA, interpersonal trust, and decision-making performance, information presentation within C2 systems must reflect human cognitive processing limits and capabilities., (© 2016, Human Factors and Ergonomics Society.)

People have a lifetime of experience in which to calibrate their self-produced locomotion with the resultant optical flow. Contrary to walking across the ground, however, walking on a treadmill produces minimal optical flow, and consequentially, a perceptual-motor aftereffect results. We demonstrate that the magnitude of this perceptual-motor aftereffect-measured by forward drift while attempting to march in-place following treadmill walking-decreases as experience walking on a treadmill is acquired over time. Experience with treadmill walking enables walking in this context to become sufficiently distinguished from walking in other contexts. Consequently, two distinct perceptual-motor calibration states are maintained, each linked to the context in which walking occurs. Experience with treadmill walking maintains perceptual-motor calibration accuracy in both walking contexts, despite changes to the relationship between perception and action.

Many amateur athletes believe that using a professional athlete's equipment can improve their performance. Such equipment can be said to be affected with positive contagion, which refers to the belief of transference of beneficial properties between animate persons/objects to previously neutral objects. In this experiment, positive contagion was induced by telling participants in one group that a putter previously belonged to a professional golfer. The effect of positive contagion was examined for perception and performance in a golf putting task. Individuals who believed they were using the professional golfer's putter perceived the size of the golf hole to be larger than golfers without such a belief and also had better performance, sinking more putts. These results provide empirical support for anecdotes, which allege that using objects with positive contagion can improve performance, and further suggest perception can be modulated by positive contagion.

Previous research has suggested that perceived distances are scaled by the action capabilities of the body. The present studies showed that when "reachability" is constrained due to a difficult grasp required to pick up an object, perceived distance to the object increases. Participants estimated the distances to tools with handle orientations that made them either easy or difficult to grasp with their dominant and nondominant hands. Right-handed participants perceived tools that were more difficult to grasp to be farther away than tools that were easier to grasp. However, perceived distance did not differ in left-handed participants. These studies suggest that, when reaching toward a target, the distance to that target is scaled in terms of how far one can effectively reach, given the type of reaching posture that is executed. Furthermore, this effect is modulated by handedness.

Perception of one's body is related not only to the physical appearance of the body, but also to the neural representation of the body. The brain contains many body maps that systematically differ between right- and left-handed people. In general, the cortical representations of the right arm and right hand tend to be of greater area in the left hemisphere than in the right hemisphere for right-handed people, whereas these cortical representations tend to be symmetrical across hemispheres for left-handers. We took advantage of these naturally occurring differences and examined perceived arm length in right- and left-handed people. When looking at each arm and hand individually, right-handed participants perceived their right arms and right hands to be longer than their left arms and left hands, whereas left-handed participants perceived both arms accurately. These experiments reveal a possible relationship between implicit body maps in the brain and conscious perception of the body.

Spatial perception is sensitive to the energetic costs required to perform intended actions. For example, hills look steeper to people who are fatigued or burdened by a heavy load. Similarly, perceived distance is also influenced by the energy required to walk or throw to a target. Such experiments demonstrate that perception is a function, not just of optical information, but also of the perceiver's potential to act and the energetic costs associated with the intended action. In the current paper, we expand on the notion of "cost" by examining perceived distance in patients diagnosed with chronic pain, a multifactorial disease, which is experienced while walking. We found that chronic pain patients perceive target distances to be farther away compared with a control group. These results indicate the physical, and perhaps emotional, costs of chronic pain affect spatial perceptions.

When people are engaged in a skilled behavior, such as occurs in sports, their perceptions relate optical information to their performance. In the present research, we demonstrate the effects of performance on size perception in golfers. We found that golfers who played better judged the hole to be bigger than did golfers who did not play as well. In follow-up laboratory experiments, participants putted on a golf mat from a location near or far from the hole and then judged the size of the hole. Participants who putted from the near location perceived the hole to be bigger than did participants who putted from the far location. Our results demonstrate that perception is influenced by the perceiver's current ability to act effectively in the environment.

This work investigates whether large-scale indoor layouts can be learned and navigated non-visually, using verbal descriptions of layout geometry that are updated, e.g. contingent on a participant's location in a building. In previous research, verbal information has been used to facilitate route following, not to support free exploration and wayfinding. Our results with blindfolded-sighted participants demonstrate that accurate learning and wayfinding performance is possible using verbal descriptions and that it is sufficient to describe only local geometric detail. In addition, no differences in learning or navigation performance were observed between the verbal study and a control study using visual input. Verbal learning was also compared to the performance of a random walk model, demonstrating that human search behavior is not based on chance decision-making. However, the model performed more like human participants after adding a constraint that biased it against reversing direction.