Contrast Analysis: A Tutorial

Contrast analysis is a relatively simple but effective statistical method for testing theoretical predictions about differences between group means against the empirical data. Despite its advantages, contrast analysis is hardly used to date, perhaps because it is not implemented in a convenient manner in many statistical software packages. This tutorial demonstrates how to conduct contrast analysis through the specification of the so-called L (the contrast or test matrix) and M matrix (the transformation matrix) as implemented in many statistical software packages, including SPSS and Stata. Through a series of carefully chosen examples, the main principles and applications of contrast analysis are explained for data obtained with between- and within-subject designs, and for designs that involve a combination of between- and within-subject factors (i.e., mixed designs). SPSS and Stata syntaxes as well as simple manual calculations are provided for both significance testing and contras Accessed 4,950 times on https://pareonline.net from May 29, 2018 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right

What Does it Mean to Be Average? The Miles per Gallon versus Gallons per Mile Paradox Revisited

In the efficiency paradox, which was introduced by Hand (1994; J R Stat Soc A, 157, 317-356), two groups of engineers are in disagreement about the average fuel efficiency of a set of cars. One group measured efficiency on a miles per gallon scale, the other on a gallons per mile scale. In the present paper, I argue against an operationalistic explanation of the efficiency paradox, by showing that the paradox is neither the result of an ambiguously defined efficiency concept, nor the result of how fuel efficiency is measured (i.e., whether a miles per gallon, or gallons per mile scale is used). The actual paradox is that the two groups of engineers have asked different statistical questions, while using the same mathematical operation. The paradox results from the fact that fuel efficiency is a derived measure, like density and speed, for which end-to-end concatenation (i.e., addition) is not straightforward. Accessed 18,393 times on https://pareonline.net from April 08, 2008 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right

Does Mediated Social Touch Succesfully Approximate Natural Social Touch?

Mediated social touch (MST) devices are upcoming. To date, experiments aimed at demonstrating whether effects of naturalistic social touch can be replicated with MST provide mixed findings. A possible explanation could be a lack of realism of current haptic displays in combination with not sufficiently taking contextual factors of social touch into account. Using a qualitative approach, our study aims to gain more insight into the influence of contextual effects on the experience of an MST, by means of exploring female participants’ experiences of receiving an MST from a male stranger versus their romantic partner. Our findings show that simultaneously feeling and seeing the touch act performed on a corporeal object can be beneficial for the MST experience. However, our findings also demonstrate that it is not self-evident to regard MST as phenomenologically equal to natural social touch, as it often fails to meet the expectations people have formed based on naturalistic social touch.To date, experiments aimed at demonstrating whether effects of naturalistic social touch can be replicated with Mediated Social Touch (MST) provide mixed findings. A possible explanation could be a lack of realism of current haptic displays in combination with not sufficiently taking contextual factors of social touch into account. Using a qualitative approach, our study aims to gain more insight into the influence of contextual effects on experience of an MST, by means of exploring female participants’ experiences of receiving an MST from a male stranger versus their romantic partner. Our findings show simultaneously feeling and seeing the touch act performed on a corporeal object can be beneficial for MST experience. However, our findings also demonstrate that it is not self-evident to regard MST as phenomenologically equal to natural social touch, as it often fails to meet expectations people formed based on naturalistic social touch.Peer reviewe

A large-scale real-life crowd steering experiment via arrow-like stimuli

We introduce "Moving Light": an unprecedented real-life crowd steering experiment that involved about 140.000 participants among the visitors of the Glow 2017 Light Festival (Eindhoven, NL). Moving Light targets one outstanding question of paramount societal and technological importance: "can we seamlessly and systematically influence routing decisions in pedestrian crowds?" Establishing effective crowd steering methods is extremely relevant in the context of crowd management, e.g. when it comes to keeping floor usage within safety limits (e.g. during public events with high attendance) or at designated comfort levels (e.g. in leisure areas). In the Moving Light setup, visitors walking in a corridor face a choice between two symmetric exits defined by a large central obstacle. Stimuli, such as arrows, alternate at random and perturb the symmetry of the environment to bias choices. While visitors move in the experiment, they are tracked with high space and time resolution, such that the efficiency of each stimulus at steering individual routing decisions can be accurately evaluated a posteriori. In this contribution, we first describe the measurement concept in the Moving Light experiment and then we investigate quantitatively the steering capability of arrow indications.Comment: 8 page

The Influence of Macroscopic Pedestrian Structures on Train Boarding Efficiency

A deeper understanding of pedestrian dynamics is essential to improve crowd flows in public spaces such as train stations. It is essential to understand both the physical and the psychological processes present in this context. However, current research on train boarding behavior is limited in scope and mainly focuses on how group level variables such as number of boarders/deboarders influence train boarding efficiency. Viewing pedestrian dynamics through a psychological lens is important for a detailed understanding of the train boarding context and to recognize target areas for improving crowd flows. At Dutch train stations, boarders follow a social norm of waiting at the train door until deboarding is complete. Although people generally adhere to this norm, the way it is executed may not be optimal for deboarding efficiency. We investigate how waiting boarders form a deboarding channel (a corridor where deboarders exit the train) which is a macroscopic structure formed by pedestrians, and how this channel in turn influences the efficiency of deboarding. Analyzing a dataset with 3278 boarding events at Utrecht Centraal Station in the Netherlands from 2017 - 2020 (a subset of a trajectory dataset that captures 100,000 trajectories per day), we found that higher numbers of boarders and a higher ratio of boarders to deboarders, reduced the width of the deboarding channel, and a lower width was associated with lower deboarding efficiency. These results shift the focus from group level variables to identifying macroscopic structures that are formed when pedestrians interact within a social system and provide specific target areas where nudges/behavioral interventions could be implemented

Emotional reactions to cybersecurity breach situations: A scenario-based survey study

Background: With the ever-expanding interconnectedness through the internet, and especially with the recent development of the Internet of Things (IoT), people are increasingly at risk for cybersecurity breaches that can have far-reaching consequences for one’s personal and professional lives, with psychological and mental health ramifications. Objective: We aim to identify the dimensional structure of emotion processes triggered by one of the most emblematic scenarios of cybersecurity breach, the hacking of one’s smart security camera, and to explore which personality characteristics systematically relate to these emotion dimensions. Methods: A total of 902 participants from the United Kingdom and the Netherlands reported their emotion processes triggered by a cybersecurity breach scenario. Moreover, they reported on their Big Five personality traits, as well as on key indicators for resilient, over-controlling (internalizing problems), and under-controlling (aggression) personality types. Results: Principal component analyses revealed a clear three-dimensional structure of emotion processes: emotional intensity, proactive vs fight/flight reactions, and affective vs cognitive/motivational reactions. Regression analyses revealed that more internalizing problems (β = .33, p < .001), resilience (β = .22, P < .001), and agreeableness (β = .12, P < .001, and less emotional stability (β = -.25, P < .001) have significant predictive value for higher emotional intensity. More internalizing problems (β = .26, P < .001), aggression (β = .25, P < .001), extraversion (β = .07, p = .01), and less resilience (β = -.19, P < .001), agreeableness (β = -.34, P < .001), consciousness (β = -.19, P < .001), and openness (β = -.22, P < .001) have significant predictive value for comparatively more fight/flight than proactive reactions. Less internalizing problems (β = -.32, P < .001), and more emotional stability (β = .14, P < .001), and aggression (β = .13, P < .001) have significant predictive value for a comparatively higher salience for cognitive/motivational than affective reactions. Conclusion: To adequately describe the emotion processes triggered by a cybersecurity breach, two more dimensions are needed over and above the general negative affectivity dimension. This multidimensional structure is further supported by the differential relationships of the emotion dimensions with personality characteristics. The discovered emotion structure could be used for consistent predictions about who is at risk to develop long-term mental well-being issues due to a cybersecurity breach experience

The Influence of Macroscopic Pedestrian Structures on Train Boarding Efficiency

A deeper understanding of pedestrian dynamics is essential to improve crowd flows in public spaces such as train stations. It is essential to understand both the physical and the psychological processes present in this context. However, current research on train boarding behavior is limited in scope and mainly focuses on how group level variables such as number of boarders/deboarders influence train boarding efficiency. Viewing pedestrian dynamics through a psychological lens is important for a detailed understanding of the train boarding context and to recognize target areas for improving crowd flows. At Dutch train stations, boarders follow a social norm of waiting at the train door until deboarding is complete. Although people generally adhere to this norm, the way it is executed may not be optimal for deboarding efficiency. We investigate how waiting boarders form a deboarding channel (a corridor where deboarders exit the train) which is a macroscopic structure formed by pedestrians, and how this channel in turn influences the efficiency of deboarding. Analyzing a dataset with 3278 boarding events at Utrecht Centraal Station in the Netherlands from 2017 - 2020 (a subset of a trajectory dataset that captures 100,000 trajectories per day), we found that higher numbers of boarders and a higher ratio of boarders to deboarders, reduced the width of the deboarding channel, and a lower width was associated with lower deboarding efficiency. These results shift the focus from group level variables to identifying macroscopic structures that are formed when pedestrians interact within a social system and provide specific target areas where nudges/behavioral interventions could be implemented

A large-scale real-life crowd steering experiment via arrow-like stimuli

We introduce “Moving Light”: an unprecedented real-life crowd steering experiment that involved about 140.000 participants among the visitors of the Glow 2017 Light Festival (Eindhoven, NL). Moving Light targets one outstanding question of paramount societal and technological importance: “can we seamlessly and systematically influence routing decisions in pedestrian crowds?” Establishing effective crowd steering methods is extremely relevant in the context of crowd management, e.g. when it comes to keeping floor usage within safety limits (e.g. during public events with high attendance) or at designated comfort levels (e.g. in leisure areas). In the Moving Light setup, visitors walking in a corridor face a choice between two symmetric exits defined by a large central obstacle. Stimuli, such as arrows, alternate at random and perturb the symmetry of the environment to bias choices. While visitors move in the experiment, they are tracked with high space and time resolution, such that the efficiency of each stimulus at steering individual routing decisions can be accurately evaluated a posteriori. In this contribution, we first describe the measurement concept in the Moving Light experiment and then we investigate quantitatively the steering capability of arrow indications