TISK 1.0: An easy-to-use Python implementation of the time-invariant string kernel model of spoken word recognition

This article describes a new Python distribution of TISK, the time-invariant string kernel model of spoken word recognition (Hannagan et al. in Frontiers in Psychology, 4, 563, 2013). TISK is an interactive-activation model similar to the TRACE model (McClelland & Elman in Cognitive Psychology, 18, 1–86, 1986), but TISK replaces most of TRACE’s reduplicated, time-specific nodes with theoretically motivated time-invariant, open-diphone nodes. We discuss the utility of computational models as theory development tools, the relative merits of TISK as compared to other models, and the ways in which researchers might use this implementation to guide their own research and theory development. We describe a TISK model that includes features that facilitate in-line graphing of simulation results, integration with standard Python data formats, and graph and data export. The distribution can be downloaded from https://github.com/maglab-uconn/TISK1.0.     

Encoding lexical tones in jTRACE: a simulation of monosyllabic spoken word recognition in Mandarin Chinese

Despite its prevalence as one of the most highly influential models of spoken word recognition, the TRACE model has yet to be extended to consider tonal languages such as Mandarin Chinese. A key reason for this is that the model in its current state does not encode lexical tone. In this report, we present a modified version of the jTRACE model in which we borrowed on its existing architecture to code for Mandarin phonemes and tones. Units are coded in a way that is meant to capture the similarity in timing of access to vowel and tone information that has been observed in previous studies of Mandarin spoken word recognition. We validated the model by first simulating a recent experiment that had used the visual world paradigm to investigate how native Mandarin speakers process monosyllabic Mandarin words (Malins & Joanisse, 2010). We then subsequently simulated two psycholinguistic phenomena: (1) differences in the timing of resolution of tonal contrast pairs, and (2) the interaction between syllable frequency and tonal probability. In all cases, the model gave rise to results comparable to those of published data with human subjects, suggesting that it is a viable working model of spoken word recognition in Mandarin. It is our hope that this tool will be of use to practitioners studying the psycholinguistics of Mandarin Chinese and will help inspire similar models for other tonal languages, such as Cantonese and Thai.     

Employee commitment and motivation: a conceptual analysis and integrative model

Theorists and researchers interested in employee commitment and motivation have not made optimal use of each other's work. Commitment researchers seldom address the motivational processes through which commitment affects behavior, and motivation researchers have not recognized important distinctions in the forms, foci, and bases of commitment. To encourage greater cross-fertilization, the authors present an integrative framework in which commitment is presented as one of several energizing forces for motivated behavior. E. A. Locke's (1997) model of the work motivation process and J. P. Meyer and L. Herscovitch's (2001) model of workplace commitments serve as the foundation for the development of this new framework. To facilitate the merger, a new concept, goal regulation, is derived from self-determination theory (E. L. Deci & R. M. Ryan, 1985) and regulatory focus theory (E. I. Higgins, 1997). By including goal regulation, it is acknowledged that motivated behavior can be accompanied by different mindsets that have particularly important implications for the explanation and prediction of discretionary work behavior.     

Generalized eta and omega squared statistics: measures of effect size for some common research designs

The editorial policies of several prominent educational and psychological journals require that researchers report some measure of effect size along with tests for statistical significance. In analysis of variance contexts, this requirement might be met by using eta squared or omega squared statistics. Current procedures for computing these measures of effect often do not consider the effect that design features of the study have on the size of these statistics. Because research-design features can have a large effect on the estimated proportion of explained variance, the use of partial eta or omega squared can be misleading. The present article provides formulas for computing generalized eta and omega squared statistics, which provide estimates of effect size that are comparable across a variety of research designs.     

Language history questionnaire: A Web-based interface for bilingual research

A Web-based interface has been developed to facilitate researchers in collecting language history information online. Most researchers use their own versions of language history questionnaires for specific studies in second language acquisition. Although these versions of questionnaires all differ from one another in some respects, there is a significant amount of overlap between them. Here we identify the crucial dimensions that most investigators consider important to include in such a questionnaire. We have examined the most commonly asked questions in 41 published questionnaires, and on the basis of our analyses we propose a general L2 language history questionnaire. Subjects can enter some or all of the information on the Web, and the results are automatically generated as an RTF output file on the user’s desktop.     

The Function of Fiction is the Abstraction and Simulation of Social Experience

ABSTRACT— Fiction literature has largely been ignored by psychology researchers because its only function seems to be entertainment, with no connection to empirical validity. We argue that literary narratives have a more important purpose. They offer models or simulations of the social world via abstraction, simplification, and compression. Narrative fiction also creates a deep and immersive simulative experience of social interactions for readers. This simulation facilitates the communication and understanding of social information and makes it more compelling, achieving a form of learning through experience. Engaging in the simulative experiences of fiction literature can facilitate the understanding of others who are different from ourselves and can augment our capacity for empathy and social inference.     

Calibration algorithm for eyetracking with unrestricted head movement

This article reports a calibration procedure that enables researchers to track movements of the eye while allowing relatively unrestricted head and/or body movement. The eye—head calibration algorithm calculates fixation point based on eye-position data acquired by a head-mounted eyetracker and corresponding head-position data acquired by a 3-D motion-tracking system. In a single experiment, we show that this procedure provides robust eye-position estimates while allowing free head movement. Although several companies offer ready-made systems for this purpose, there is no literature available that makes it possible for researchers to explore the details of the calibration procedures used by these systems. By making such details available, we hope to facilitate the development of cost-effective, nonproprietary eyetracking solutions.     

The stimulating and inhibiting effects of weapons on Aggressive behavior

Evidence is presented suggesting that firearms violence is an important social problem. Research strongly suggests that the effectiveness of firearms as a cause of death and injury may be due to their widespread availability, their lethality, and the impulsivity of their use. The investigation of a possible causal link between firearms and impulsive aggression led to Berkowitz and LePage's (1967) weapons effect experiment. The results suggested that weapons can increase the instigation to aggression in aroused an uninhibited individuals. The researchers reasoned that weapons might stimulate aggression by classical conditioning processes resulting from learned associations between aggressive acts and weapons. Although a few studies have failed to reproduce an aggression-enhancing effect of weapons, the original finding has been replicated in several countries with diverse subject groups both in field and laboratory settings. However, these studies also indicate that many individuals may react with anxiety or fear in the presence of weapons and inhibit aggressive reactions. Manipulations of evaluation apprehension, subject suspiciousness, and/or hypothesis awareness about the purpose of the weapons in the experiments all seem to lead to reduced levels of aggressive response in the presence of weapons. These findings offer a possible explanation for the few failures to replicate the original weapons effect; if researchers used apprehensive subjects or subjects who were aware of possible experimental deceptions, they were more likely to observe an inhibitory reaction rather than an aggression-enhancing effect of weapons.     

Estimating Success in Predicting a Variable with Nominal Measurement Using Other Variables with Nominal Measurements

In this article we are concerned with the situation where one is estimating the outcome of a variable Y, with nominal measurement, on the basis of the outcomes of several predictor variables, X 1, X 2, ..., X r, each with nominal measurement. We assume that we have a random sample from the population. Here we are interested in estimating p, the probability of successfully predicting a new Y from the population, given the X measurements for this new observation. We begin by proposing an estimator, p_a, which is the success rate in predicting Y from the current sample. We show that this estimator is always biased upwards. We then propose a second estimator, p_b, which divides the original sample into two groups, a holdout group and a training group, in order to estimate p. We show that procedures such as these are always biased downwards, no matter how we divide the original sample into the two groups. Because one of these estimators tends to overestimate p while the other tends to underestimate p, we propose as a heuristic solution to use the mean of these two estimators, p_c, as an estimator for p. We then perform several simulation studies to compare the three estimators with respect to both bias and MSE. These simulations seem to confirm that $ p c is a better estimator than either of the other two.     

Using focus groups to facilitate culturally anchored research

Scholars have acknowledged the need to anchor scientific knowledge about social and psychological processes in the norms, values, and experiences of the partticular population under study. This article describes how focus groups can be incorporated into the planning stages of a research pogram to facilitate these goals. After a brief overview of teh central components of focus group research, and example from a program of research involving dual-earner African American families is used to as an illustration. The article describes how (a) the identification of cultural knowledge and (b)access to the language participants use to think and talk about a topic can help researchers formulate a conceptual framework, identify important constructs, and develop appropriate instruments for assessing constructs. Some strengths and limitations of focus group research are discussed.     

Connectionist modeling of speech perception.

Connectionist models of perception and cognition, including the process of deducing meaningful messages from patterns of acoustic waves emitted by vocal tracts, are developed and refined as human understanding of brain function, psychological processes, and the properties of massively parallel architectures advances. The present article presents several important contributions from diverse points of view in the area of connectionist modeling of speech perception and discusses their relative merits with respect to specific theoretical issues and empirical findings. TRACE, the Elman/Norris net, and Adaptive Resonance Theory constitute pivotal points exemplifying overall modeling success, progress in temporal representation, and plausible modeling of learning, respectively. Other modeling efforts are presented for the specific insights they offer, and the article concludes with a discussion of computational versus dynamic modeling of phonological processes.     

The Use of the Term Virtual Reality in Post-Stroke Rehabilitation: A Scoping Review and Commentary

Virtual reality (VR) offers many opportunities for post-stroke rehabilitation. However, “VR” can refer to several types of computer-based rehabilitation systems. Since these systems may impact the feasibility and the efficacy of VR interventions, consistent terminology is important. In this study, we aimed to optimize the terminology for VR-based post-stroke rehabilitation by assessing whether and how review papers on this topic defined VR and what types of mixed reality systems were discussed. In addition, this review can inspire the use of consistent terminology for other researchers working with VR. We assessed the use of the term VR in review papers on post-stroke rehabilitation extracted from Scopus, Web of Science and PubMed. We also developed a taxonomy distinguishing 16 mixed reality systems based on three factors: immersive versus semi-immersive displays, the way in which real and virtual information is mixed, and the main input device. 64% of the included review papers (N = 121) explicitly defined VR and 33% of them described different subtypes of VR, with immersive and non-immersive VR as the most common distinction. The most frequently discussed input devices were motion-capture cameras and handheld devices, while regular 2D monitors were the most frequently mentioned output devices. Our analysis revealed that reviews on post-stroke VR rehabilitation did not or only broadly defined “VR” and did not focus on a specific system. Since the efficacy and feasibility of rehabilitation may depend on the specific system, we propose a new data-driven taxonomy to distinguish different systems, which is expected to facilitate communication amongst researchers and clinicians working with virtual reality.     

Analysis and meta-analysis of single-case designs: An introduction

The last 10 years have seen great progress in the analysis and meta-analysis of single-case designs (SCDs). This special issue includes five articles that provide an overview of current work on that topic, including standardized mean difference statistics, multilevel models, Bayesian statistics, and generalized additive models. Each article analyzes a common example across articles and presents syntax or macros for how to do them. These articles are followed by commentaries from single-case design researchers and journal editors. This introduction briefly describes each article and then discusses several issues that must be addressed before we can know what analyses will eventually be best to use in SCD research. These issues include modeling trend, modeling error covariances, computing standardized effect size estimates, assessing statistical power, incorporating more accurate models of outcome distributions, exploring whether Bayesian statistics can improve estimation given the small samples common in SCDs, and the need for annotated syntax and graphical user interfaces that make complex statistics accessible to SCD researchers. The article then discusses reasons why SCD researchers are likely to incorporate statistical analyses into their research more often in the future, including changing expectations and contingencies regarding SCD research from outside SCD communities, changes and diversity within SCD communities, corrections of erroneous beliefs about the relationship between SCD research and statistics, and demonstrations of how statistics can help SCD researchers better meet their goals.     

The Bioterrorism Threat and Dual-use Biotechnological Research: An Israeli Perspective

Israel has a long history of concern with chemical and biological threats, since several hostile states in the Middle East are likely to possess such weapons. The Twin-Tower terrorist attacks and Anthrax envelope scares of 2001 were a watershed for public perceptions of the threat of unconventional terror in general and of biological terror in particular. New advances in biotechnology will only increase the ability of terrorists to exploit the burgeoning availability of related information to develop ever-more destructive bioweapons. Many areas of modern biological research are unavoidably dual-use by nature. They thus have a great potential for both help and harm; and facilitating the former while preventing the latter remains a serious challenge to researchers and governments alike. This article addresses how Israel might best (1) prevent hostile elements from obtaining, from Israel’s biological research system, materials, information and technologies that might facilitate their carrying out a biological attack, while (2) continuing to promote academic openness, excellence and other hallmarks of that system. This important and sensitive issue was assessed by a special national committee, and their recommendations are presented and discussed. One particularly innovative element is the restructuring and use of Israel’s extensive biosafety system to also address biosecurity goals, with minimal disruption or delay.     

Family therapy and the notion of accountability: With reference to trends in individual psychotherapy

Family therapy both overseas and within Australia has seen a rapid rise in popularity and general acceptance as an important therapeutic intervention. Along with the growth in interest, however, has come an increased demand for accountability. The foundation stone for the accountability issue surrounds the questions of therapy efficacy. How effective is family therapy, and, indeed, if it is effective, what are the active elements or ingredients which facilitate positive client change? Three groups, in particular, have vested interests in questions relating to the effectiveness of family therapy: researchers, therapists, and consumers. Although both researchers and therapists, for a variety of reasons, have been concerned with the effectiveness of treatment for some time, it has only been relatively recently that there has been a concerted push from various sections of the consumer group, including administrators, legislators, and policy makers. The consumer group is now providing pressure on professionals as to what we have done, and are doing, to demonstrate that family therapy really “works.”     

Addressing Moderated Mediation Hypotheses: Theory,Methods, and Prescriptions

This article provides researchers with a guide to properly construe and conduct analyses of conditional indirect effects, commonly known as moderated mediation effects. We disentangle conflicting definitions of moderated mediation and describe approaches for estimating and testing a variety of hypotheses involving conditional indirect effects. We introduce standard errors for hypothesis testing and construction of confidence intervals in large samples but advocate that researchers use bootstrapping whenever possible. We also describe methods for probing significant conditional indirect effects by employing direct extensions of the simple slopes method and Johnson-Neyman technique for probing significant interactions. Finally, we provide an SPSS macro to facilitate the implementation of the recommended asymptotic and bootstrapping methods. We illustrate the application of these methods with an example drawn from the Michigan Study of Adolescent Life Transitions, showing that the indirect effect of intrinsic student interest on mathematics performance through teacher perceptions of talent is moderated by student math self-concept.     

Changing the logic of replication: A case from infant studies

Among infant researchers there is growing concern regarding the widespread practice of undertaking studies that have small sample sizes and employ tests with low statistical power (to detect a wide range of possible effects). For many researchers, issues of confidence may be partially resolved by relying on replications. Here, we bring further evidence that the classical logic of confirmation, according to which the result of a replication study confirms the original finding when it reaches statistical significance, could be usefully abandoned. With real examples taken from the infant literature and Monte Carlo simulations, we show that a very wide range of possible replication results would in a formal statistical sense constitute confirmation as they can be explained simply due to sampling error. Thus, often no useful conclusion can be derived from a single or small number of replication studies. We suggest that, in order to accumulate and generate new knowledge, the dichotomous view of replication as confirmatory/disconfirmatory can be replaced by an approach that emphasizes the estimation of effect sizes via meta-analysis. Moreover, we discuss possible solutions for reducing problems affecting the validity of conclusions drawn from meta-analyses in infant research.     

Common and distinctive features in stimulus similarity: A modified version of the contrast model

Featural representations of similarity data assume that people represent stimuli in terms of a set of discrete properties. In this article, we consider the differences in featural representations that arise from making four different assumptions about how similarity is measured. Three of these similarity models— the common features model, the distinctive features model, and Tversky’s seminal contrast model—have been considered previously. The other model is new and modifies the contrast model by assuming that each individual feature only ever acts as a common or distinctive feature. Each of the four models is tested on previously examined similarity data, relating to kinship terms, and on a new data set, relating to faces. In fitting the models, we have used the geometric complexity criterion to balance the competing demands of data-fit and model complexity. The results show that both common and distinctive features are important for stimulus representation, and we argue that the modified contrast model combines these two components in a more effective and interpretable way than Tversky’s original formulation.