EQUIWORD: A software application for the automatic creation of truly equivalent word lists

Word lists are most commonly used in the investigation of human memory. To prevent transfer effects, repeated measures of memory for words require multiple lists of different words. Yet, the psycholinguistic properties of all word lists employed should match as closely as possible to avoid confounding with the independent variable(s) in question. Although comprehensive databases for word norms exist, to our knowledge no tool is available that automates the creation of such equivalent word lists. Instead, matching different lists is often accomplished prima facie. We have therefore developed a Windows program called EQUIWORD that completely automates the creation of word lists that are truly parallel with respect to a wide range of attributes. EQUIWORD takes psycholinguistic databases of different formats as input and computes several coefficients of distance for every possible word pairing. Program output consists of a list of all word pairs sorted according to their distance. On that basis, creating equivalent word lists is simply done by selecting the pairs with the lowest distance coefficients.     

A note on ROC analysis and non-parametric estimate of sensitivity

In the signal detection paradigm, the non-parametric index of sensitivity A′, as first introduced by Pollack and Norman (1964), is a popular alternative to the more traditional d′ measure of sensitivity. Smith (1995) clarified a confusion about the interpretation of A′ in relation to the area beneath proper receiver operating characteristic (ROC) curves, and provided a formula (which he called A′′) for this commonly held interpretation. However, he made an error in his calculations. Here, we rectify this error by providing the correct formula (which we call A) and compare the discrepancy that would have resulted. The corresponding measure for bias b is also provided. Since all such calculations apply to “proper” ROC curves with non-decreasing slopes, we also prove, as a separate result, the slope-monotonicity of ROC curves generated by likelihood-ratio criterion.This revised article was published online in August 2005 with the PDF paginated correctly.     

Recombinative generalization of within-syllable units in prereading children

This study demonstrates recombinative generalization of within-syllable units in prereading children. Three kindergarten children learned to select printed consonant-vowel-consonant words upon hearing the corresponding spoken words. The words were taught in sets; there were six sets, presented consecutively. Within sets, the four words that were taught had overlapping letters, for example, sat, mat, sop, and sug. Tests for recombinative generalization determined whether the children selected novel words with the same components as the trained words (e.g., mop and mug). Two children demonstrated recombinative generalization after one training set, and the 3rd demonstrated it after two training sets. In contrast, 2 other children, who received tests but no training, showed low accuracy across six sets. The 3 experimental children then demonstrated highly accurate printed-word-to-picture matching, and named the majority of the printed words. These findings are a promising step in the development of a computerized instructional technology for reading.     

Knowledge junkies or careerbuilders? A mixed-methods approach to exploring the determinants of students' intention to earn a PhD

What are the determinants of students' interest in earning a PhD? In this study, we use a mixed-methods approach to pursue this question. Based on qualitative interview data, we develop a model in which academic motivation and academic achievement interact with contextual factors such as working conditions to influence career intentions. We then test this model using a sample of 229 students currently enrolled in master-level courses of study at a German university. Our results speak to the role of intrinsic versus extrinsic motivations in the context of PhD intentions. In contrast to our expectations, results suggest that while intrinsic life aspirations and the intellectual challenge of gaining a PhD play a significant role for students' intention to pursue a PhD, extrinsic life aspirations and contextual determinants seem to be less influential. Furthermore, results highlight the importance of gaining familiarity and experience with academic work for students' career decisions.     

Prismatic Equivalence – A New Case of Underdetermination: Goethe vs. Newton on the Prism Experiments

Goethe's objections to Newton's theory of light and colours are better than often acknowledged. You can accept the most important elements of these objections without disagreeing with Newton about light and colours. As I will argue, Goethe exposed a crucial weakness of Newton's methodological self-assessment. Newton believed that with the help of his prism experiments, he could prove that sunlight was composed of variously coloured rays of light. Goethe showed that this step from observation to theory is more problematic than Newton wanted to admit. By insisting that the step to theory is not forced upon us by the phenomena, Goethe revealed our own free, creative contribution to theory construction. And Goethe's insight is surprisingly significant, because he correctly claimed that all of the results of Newton's prism experiments fit a theoretical alternative equally well. If this is correct, then by suggesting an alternative to a well-established physical theory, Goethe developed the problem of underdetermination a century before Duhem and Quine's famous arguments.     

Only time will tell – why temporal information is essential for our neuroscientific understanding of semantics

Theoretical developments about the nature of semantic representations and processes should be accompanied by a discussion of how these theories can be validated on the basis of empirical data. Here, I elaborate on the link between theory and empirical research, highlighting the need for temporal information in order to distinguish fundamental aspects of semantics. The generic point that fast cognitive processes demand fast measurement techniques has been made many times before, although arguably more often in the psychophysiological community than in the metabolic neuroimaging community. Many reviews on the neuroscience of semantics mostly or even exclusively focus on metabolic neuroimaging data. Following an analysis of semantics in terms of the representations and processes involved, I argue that fundamental theoretical debates about the neuroscience of semantics can only be concluded on the basis of data with sufficient temporal resolution. Any “semantic effect” may result from a conflation of long-term memory representations, retrieval and working memory processes, mental imagery, and episodic memory. This poses challenges for all neuroimaging modalities, but especially for those with low temporal resolution. It also throws doubt on the usefulness of contrasts between meaningful and meaningless stimuli, which may differ on a number of semantic and non-semantic dimensions. I will discuss the consequences of this analysis for research on the role of convergence zones or hubs and distributed modal brain networks, top-down modulation of task and context as well as interactivity between levels of the processing hierarchy, for example in the framework of predictive coding.     

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.     

A Qualitative Study of Healthcare Providers’ Perspectives on the Implications of Genome-Wide Testing in Pediatric Clinical Practice

The utilization of genome-wide chromosomal microarray analysis (CMA) in pediatric clinical practice provides an opportunity to consider how genetic diagnostics is evolving, and to prepare for the clinical integration of genome-wide sequencing technologies. We conducted semi-structured interviews with 15 healthcare providers (7 genetic counselors, 4 medical geneticists, and 4 non-genetics providers) to investigate the impact of CMA on clinical practice, and implications for providers, patients and families. Interviews were analyzed qualitatively using content analysis. Most providers reported that genomic testing enhanced their professional experience and was beneficial to patients, primarily due to the improved diagnostic rate compared with earlier chromosomal studies. Other effects on practice included moving towards genotype-first diagnosis and broadening indications for chromosomal testing. Opinions varied concerning informed consent and disclosure of results. The duty to disclose incidental findings (IFs) was noted; however concerns were raised about potential psychosocial harms of disclosing pre-symptomatic findings. Tensions were revealed between the need for comprehensive informed consent for all families and the challenges of communicating time-consuming and potentially anxiety-provoking information regarding uncertain and incidental findings that may be relevant only in rare cases. Genetic counselors can play an important role in liaising with families, health professionals and testing laboratories, providing education and guidance to non-genetics providers, and enabling families to receive adequate pre-and post-test information and follow-up care.