MouseTracker: Software for studying real-time mental processing using a computer mouse-tracking method

In the present article, we present a software package, MouseTracker, that allows researchers to use a computer mouse-tracking method for assessing real-time processing in psychological tasks. By recording the streaming x-, y-coordinates of the computer mouse while participants move the mouse into one of multiple response alternatives, motor dynamics of the hand can reveal the time course of mental processes. MouseTracker provides researchers with fine-grained information about the real-time evolution of participant responses by sampling 60–75 times/sec the online competition between multiple response alternatives. MouseTracker allows researchers to develop and run experiments and subsequently analyze mouse trajectories in a user-interactive, graphics-based environment. Experiments may incorporate images, letter strings, and sounds. Mouse trajectories can be processed, averaged, visualized, and explored, and measures of spatial attraction/curvature, complexity, velocity, and acceleration can be computed. We describe the software and the method, and we provide details on mouse trajectory analysis. We validate the software by demonstrating the accuracy and reliability of its trajectory and reaction time data. The latest version of MouseTracker is freely available at http://mousetracker.jbfreeman.net.     

How to perform multiblock component analysis in practice

To explore structural differences and similarities in multivariate multiblock data (e.g., a number of variables have been measured for different groups of subjects, where the data for each group constitute a different data block), researchers have a variety of multiblock component analysis and factor analysis strategies at their disposal. In this article, we focus on three types of multiblock component methods—namely, principal component analysis on each data block separately, simultaneous component analysis, and the recently proposed clusterwise simultaneous component analysis, which is a generic and flexible approach that has no counterpart in the factor analysis tradition. We describe the steps to take when applying those methods in practice. Whereas plenty of software is available for fitting factor analysis solutions, up to now no easy-to-use software has existed for fitting these multiblock component analysis methods. Therefore, this article presents the MultiBlock Component Analysis program, which also includes procedures for missing data imputation and model selection.     

The influence of calibration method and eye physiology on eyetracking data quality

Recording eye movement data with high quality is often a prerequisite for producing valid and replicable results and for drawing well-founded conclusions about the oculomotor system. Today, many aspects of data quality are often informally discussed among researchers but are very seldom measured, quantified, and reported. Here we systematically investigated how the calibration method, aspects of participants’ eye physiologies, the influences of recording time and gaze direction, and the experience of operators affect the quality of data recorded with a common tower-mounted, video-based eyetracker. We quantified accuracy, precision, and the amount of valid data, and found an increase in data quality when the participant indicated that he or she was looking at a calibration target, as compared to leaving this decision to the operator or the eyetracker software. Moreover, our results provide statistical evidence of how factors such as glasses, contact lenses, eye color, eyelashes, and mascara influence data quality. This method and the results provide eye movement researchers with an understanding of what is required to record high-quality data, as well as providing manufacturers with the knowledge to build better eyetrackers.     

Quantification of brain lesions using interactive automated software

We developed an interactive program, Analysis of Brain Lesions (ABLe) so that researchers studying the effects of brain lesions on cognition could have a user-friendly tool that could quantitatively characterize such lesions. The program was prepared in Tcl/Tk and will run on any UNIX or PC LINUX platform with the MEDx medical imaging software package. The ABLe is almost completely automated and determines the brain lesion size as well as which cytoarchitectonic brain regions (Brodmann areas) are contained within the boundaries of the lesion. Lesion data from multiple subjects can be grouped together and the degree of lesion overlap displayed. All images are analyzed and displayed within standard Talairach coordinate space, and the precision of the match between the ABLe Brodmann area graphics and the subject/patient brain is easily confirmed. The program is the first easy-to-use software that contains these specific features and is available for interested researchers with a background in lesion analysis.     

Approximated adjusted fractional Bayes factors: A general method for testing informative hypotheses

Informative hypotheses are increasingly being used in psychological sciences because they adequately capture researchers’ theories and expectations. In the Bayesian framework, the evaluation of informative hypotheses often makes use of default Bayes factors such as the fractional Bayes factor. This paper approximates and adjusts the fractional Bayes factor such that it can be used to evaluate informative hypotheses in general statistical models. In the fractional Bayes factor a fraction parameter must be specified which controls the amount of information in the data used for specifying an implicit prior. The remaining fraction is used for testing the informative hypotheses. We discuss different choices of this parameter and present a scheme for setting it. Furthermore, a software package is described which computes the approximated adjusted fractional Bayes factor. Using this software package, psychological researchers can evaluate informative hypotheses by means of Bayes factors in an easy manner. Two empirical examples are used to illustrate the procedure.     

CircE: An R implementation of Browne’s circular stochastic process model

In confirmatory analysis of whether data have a circumplex structure, Browne’s (1992) model has played a major role. However, implementation of this model requires a dedicated program, CIRCUM, because the analysis routine is not integrated in any of the most widely used statistical software packages. Hence, data entry and graphical representation of the results require the use of one or more additional programs. We propose a package for the R statistical environment, termed CircE, that can be used to enter or import data, implement Browne’s confirmatory analysis, and graphically represent the results. Using this new software, we put forward a new approach to assess the sustainability of theoretical models when the analysis is carried out at the level of questionnaire items. The CircE package (for either Mac OS X or Windows) and additional files may be downloaded from http://brm.psychonomic-journals.org/content/supplemental.     

Could millisecond timing errors in commonly used equipment be a cause of replication failure in some neuroscience studies?

Neuroscience is a rapidly expanding field in which complex studies and equipment setups are the norm. Often these push boundaries in terms of what technology can offer, and increasingly they make use of a wide range of stimulus materials and interconnected equipment (e.g., magnetic resonance imaging, electroencephalography, magnetoencephalography, eyetrackers, biofeedback, etc.). The software that bonds the various constituent parts together itself allows for ever more elaborate investigations to be carried out with apparent ease. However, research over the last decade has suggested a growing, yet underacknowledged, problem with obtaining millisecond-accurate timing in some computer-based studies. Crucially, timing inaccuracies can affect not just response time measurements, but also stimulus presentation and the synchronization between equipment. This is not a new problem, but rather one that researchers may have assumed had been solved with the advent of faster computers, state-of-the-art equipment, and more advanced software. In this article, we highlight the potential sources of error, their causes, and their likely impact on replication. Unfortunately, in many applications, inaccurate timing is not easily resolved by utilizing ever-faster computers, newer equipment, or post-hoc statistical manipulation. To ensure consistency across the field, we advocate that researchers self-validate the timing accuracy of their own equipment whilst running the actual paradigm in situ.     

ELIA: A software application for integrating spoken language and eye movements

We have developed a new software application, Eye-gaze Language Integration Analysis (ELIA), which allows for the rapid integration of gaze data with spoken language input (either live or prerecorded). Specifically, ELIA integrates E-Prime output and/or .csv files that include eye-gaze and real-time language information. The process of combining eye movements with real-time speech often involves multiple error-prone steps (e.g., cleaning, transposing, graphing) before a simple time course analysis plot can be viewed or before data can be imported into a statistical package. Some of the advantages of this freely available software include (1) reducing the amount of time spent preparing raw eye-tracking data for analysis; (2) allowing for the quick analysis of pilot data in order to identify issues with experimental design; (3) facilitating the separation of trial types, which allows for the examination of supplementary effects (e.g., order or gender effects); and (4) producing standard output files (i.e., .csv files) that can be read by numerous spreadsheet packages and transferred to any statistical software.     

中介效应的检验方法和效果量测量:回顾与展望

通过中介效应检验方法之间的比较和效果量指标之间的比较,建议放弃将总效应c显著作为中介效应检验的前提条件,放弃基于直接效应c'显著性的完全和部分中介的提法,推荐使用偏差校正的百分位Bootstrap法直接对中介效应ab进行检验,使用κ²、R_med²等中介效果量指标并报告效果量的置信区间。作为示例,用R软件的MBESS软件包对某消防员饮食健康调查进行了中介效应检验和效果量测量。随后展望了中介效应检验方法和效果量测量的拓展方向。     

Validating the Restricted Focus Viewer: A study using eye-movement tracking

Investigation of cognitive processes and visual attention during problem-solving tasks is an important part of understanding human reasoning. Eyetracking technology has proven to have many benefits in revealing visual attention patterns. However, the high price of accurate eyetrackers and the difficulties associated with using them represent major obstacles to their wider application. Therefore, previous studies have sought to find alternatives to eyetracking. The Restricted Focus Viewer (RFV) brings a small part of an otherwise blurred display to the focus of visual attention: A user controls what part of the screen is in focus by using a computer mouse and explicitly selecting the area to be shown in focus. Recently, some studies have employed the RFV to investigate cognitive behavior of users, and some researchers have even enhanced the tool to study usability. We replicated a previous RFV-based study while also recording gaze data. We compared the attention allocation in time and space as reported by the RFV and an eyetracker. Further, we investigated the effects of RFV’s display blurring on the visual attention allocation of 18 novice and expert programmers. Our results indicate that the data obtained from the two tools differ. Also, the RFV-blurring interferes with the strategies utilized by experts, and has an effect on fixation duration. However, task performance was preserved.     

Mousetrap: An integrated,open-source mouse-tracking package

Mouse-tracking – the analysis of mouse movements in computerized experiments – is becoming increasingly popular in the cognitive sciences. Mouse movements are taken as an indicator of commitment to or conflict between choice options during the decision process. Using mouse-tracking, researchers have gained insight into the temporal development of cognitive processes across a growing number of psychological domains. In the current article, we present software that offers easy and convenient means of recording and analyzing mouse movements in computerized laboratory experiments. In particular, we introduce and demonstrate the mousetrap plugin that adds mouse-tracking to OpenSesame, a popular general-purpose graphical experiment builder. By integrating with this existing experimental software, mousetrap allows for the creation of mouse-tracking studies through a graphical interface, without requiring programming skills. Thus, researchers can benefit from the core features of a validated software package and the many extensions available for it (e.g., the integration with auxiliary hardware such as eye-tracking, or the support of interactive experiments). In addition, the recorded data can be imported directly into the statistical programming language R using the mousetrap package, which greatly facilitates analysis. Mousetrap is cross-platform, open-source and available free of charge from https://github.com/pascalkieslich/mousetrap-os.     

Modelling human problem solving with data from an online game

Since the beginning of cognitive science, researchers have tried to understand human strategies in order to develop efficient and adequate computational methods. In the domain of problem solving, the travelling salesperson problem has been used for the investigation and modelling of human solutions. We propose to extend this effort with an online game, in which instances of the travelling salesperson problem have to be solved in the context of a game experience. We report on our effort to design and run such a game, present the data contained in the resulting openly available data set and provide an outlook on the use of games in general for cognitive science research. In addition, we present three geometrical models mapping the starting point preferences in the problems presented in the game as the result of an evaluation of the data set.     

Real-time sharing of gaze data between multiple eye trackers–evaluation,tools, and advice

Technological advancements in combination with significant reductions in price have made it practically feasible to run experiments with multiple eye trackers. This enables new types of experiments with simultaneous recordings of eye movement data from several participants, which is of interest for researchers in, e.g., social and educational psychology. The Lund University Humanities Laboratory recently acquired 25 remote eye trackers, which are connected over a local wireless network. As a first step toward running experiments with this setup, demanding situations with real time sharing of gaze data were investigated in terms of network performance as well as clock and screen synchronization. Results show that data can be shared with a sufficiently low packet loss (0.1 %) and latency (M = 3 ms, M A D = 2 ms) across 8 eye trackers at a rate of 60 Hz. For a similar performance using 24 computers, the send rate needs to be reduced to 20 Hz. To help researchers conduct similar measurements on their own multi-eye-tracker setup, open source software written in Python and PsychoPy are provided. Part of the software contains a minimal working example to help researchers kick-start experiments with two or more eye trackers.     

Twice random,once mixed: Applying mixed models to simultaneously analyze random effects of language and participants

Psychologists, psycholinguists, and other researchers using language stimuli have been struggling for more than 30 years with the problem of how to analyze experimental data that contain two crossed random effects (items and participants). The classical analysis of variance does not apply; alternatives have been proposed but have failed to catch on, and a statistically unsatisfactory procedure of using two approximations (known as F ₁ and F ₂) has become the standard. A simple and elegant solution using mixed model analysis has been available for 15 years, and recent improvements in statistical software have made mixed models analysis widely available. The aim of this article is to increase the use of mixed models by giving a concise practical introduction and by giving clear directions for undertaking the analysis in the most popular statistical packages. The article also introduces the djmixed add-on package for SPSS, which makes entering the models and reporting their results as straightforward as possible.     

InterFace: A software package for face image warping,averaging, and principal components analysis

We describe InterFace, a software package for research in face recognition. The package supports image warping, reshaping, averaging of multiple face images, and morphing between faces. It also supports principal components analysis (PCA) of face images, along with tools for exploring the “face space” produced by PCA. The package uses a simple graphical user interface, allowing users to perform these sophisticated image manipulations without any need for programming knowledge. The program is available for download in the form of an app, which requires that users also have access to the (freely available) MATLAB Runtime environment.     

The use of Tholos software for combining measures of mental workload: Toward theoretical and methodological improvements

Mental workload is a concept central to a range of disciplines (including cognitive psychology and ergonomics) that has given rise to various theoretical and methodological debates. As a result, researchers have used a number of techniques for measuring mental workload. Traditionally, three categories of measurement technique have been recognized: performance measures (e.g., the dual-task paradigm), subjective measures (e.g., rating scales), and physiological measures (e.g., heart, respiration, and blink rates). Each technique has advantages and limitations; however, some limitations may prevent an accurate evaluation of the mental workload. In this article, we focus on the benefits of combining multiple measures of mental workload. However, because combining several techniques is a very complex process, we have developed the Tholos software in an attempt to reduce this complexity. This software package uses measures from each of the three categories: a dual-task paradigm with auditory signals; the National Aeronautics and Space Administration task load index (NASA-TLX) scale and its simplified version, the “raw” task load index (RTLX); and physiological (such as pupil-dilation) measurements with which our software can merge results from the dual-task paradigm. To illustrate the benefits of using Tholos, we describe a puzzle-solving experiment in which we combined multiple measures of mental workload. The results indicate the importance of combining multiple measures to build upon the theoretical and methodological foundations of mental workload.     

Nonnaïveté among Amazon Mechanical Turk workers: Consequences and solutions for behavioral researchers

Crowdsourcing services—particularly Amazon Mechanical Turk—have made it easy for behavioral scientists to recruit research participants. However, researchers have overlooked crucial differences between crowdsourcing and traditional recruitment methods that provide unique opportunities and challenges. We show that crowdsourced workers are likely to participate across multiple related experiments and that researchers are overzealous in the exclusion of research participants. We describe how both of these problems can be avoided using advanced interface features that also allow prescreening and longitudinal data collection. Using these techniques can minimize the effects of previously ignored drawbacks and expand the scope of crowdsourcing as a tool for psychological research.     

Bayesian inference for psychology. Part I: Theoretical advantages and practical ramifications

Bayesian parameter estimation and Bayesian hypothesis testing present attractive alternatives to classical inference using confidence intervals and p values. In part I of this series we outline ten prominent advantages of the Bayesian approach. Many of these advantages translate to concrete opportunities for pragmatic researchers. For instance, Bayesian hypothesis testing allows researchers to quantify evidence and monitor its progression as data come in, without needing to know the intention with which the data were collected. We end by countering several objections to Bayesian hypothesis testing. Part II of this series discusses JASP, a free and open source software program that makes it easy to conduct Bayesian estimation and testing for a range of popular statistical scenarios (Wagenmakers et al. this issue).