Beyond the five-user assumption: Benefits of increased sample sizes in usability testing

It is widely assumed that 5 participants suffice for usability testing. In this study, 60 users were tested and random sets of 5 or more were sampled from the whole, to demonstrate the risks of using only 5 participants and the benefits of using more. Some of the randomly selected sets of 5 participants found 99% of the problems; other sets found only 55%. With 10 users, the lowest percentage of problems revealed by any one set was increased to 80%, and with 20 users, to 95%.     

Evidence for abstract, schematic knowledge of three spatial diagram representations

Spatial diagram representations such as hierarchies, matrices, and networks are important tools for thinking. Our data suggest that college students possess abstract schemas for these representations that include at least rudimentary information about their applicability conditions. In Experiment 1, subjects were better able to select the appropriate spatial diagram representation for a problem when cued to use general category information in memory about those representations than when cued to use specific example problems given during the experiment. The results of Experiment 2 showed that the superior performance in the general category condition was not based on a comparison of the test problems with examples in memory. The results of Experiment 3 showed that the superior performance was not due to learning that occurred during the experiment or to transfer appropriate processing. The General Discussion section considers the nature of students' representation schemas and the question of why college students have only rudimentary schemas for common and widely applicable diagrammatic representations.     

Does Alternating Between Masculine and Feminine Pronouns Eliminate Perceived Gender Bias in Text?

This study explores whether alternating betweenthe pronouns he and she ina text is an effective way to avoid sexist language.Participants were psychology students at a largemidwestern university and were predominately White and frommiddle-class backgrounds. Students read two versions ofan essay, one that alternated between masculine andfeminine pronouns and one that exclusively used paired, he or she-type pronouns. Readersperceived the alternating version to be biased in favorof females and lower in overall quality than the pairedversion. However, the alternating version appeared to be more effective at combating sexism,suggesting an alternating strategy may be desirable forauthors with this goal. If the author is not primarilyconcerned with increasing readers' awareness of gender issues, techniques such as pluralization or thesingular they may be moreappropriate.     

Comparison in the Development of Categories

Recent research on children's word learning has led to a paradox. Although word learning appears to be a deep source of insight into conceptual knowledge for children, preschoolers often categorize objects on the basis of shallow perceptual features such as shape. The current studies seek to resolve this discrepancy. We suggest that comparing multiple instances of a category enables children to extract deeper relational commonalities among category members. We examine 4-year-olds' categorization behaviors when asked to select a match for a target object (e.g., an apple) between a perceptually similar, out-of-kind object (e.g., a balloon) and a perceptually different category match (e.g., a banana). Children who learn a novel word as a label for multiple instances of the category are more likely to select the category match over the perceptual match. Children who learn a label for only one instance are equally likely to select either alternative. This effect is present even when individual target instances are more perceptually similar to the perceptual choice than to the category choice. We conclude that structural alignment processes may be important in the development of category understanding.     

Gender Differences in the Relation Between Neighborhood Quality and Cardiovascular Reactivity in African American Adolescents1

Although research on the influence of neighborhoods on the development of youth is growing, few researchers have examined the impact of neighborhood quality on physiological outcomes or across gender. The present experiment examined gender differences in the association of neighborhood quality and cardiovascular reactivity (increased blood pressure, BP, in response to stress) among 77 healthy African American adolescents (46% male; M age = 14 years). Participants took part in a cold-face stimulus task to determine reactivity scores. After controlling for baseline BP, family income, and parental education, poorer neighborhood quality was associated with increases in both systolic and diastolic BP to the cold-face task for females, and decreases in BP for males. Adolescents’ reports of life stress and support from family members did not explain the differential effect of neighborhood quality across gender. Implications for future research are discussed.     

The Powerful Other: How Divine Control Shapes the Relationship Between Personal Control and Psychological Distress

In the sociological study of mental health, the sense of personal control represents a core psychological resource, but some studies document a curvilinear association between personal control and depressive symptoms. This body of research is largely secular in orientation, even though research also demonstrates that some individuals believe in an involved and engaged Powerful Other (e.g., God). We evaluate if such beliefs moderate the relationship between personal control and depression. Using data from the 2005 Work, Stress, and Health Study in the United States (N = 1,791), we first demonstrate that the sense of personal control has an overall curvilinear association with depression, in line with previous research. Then, we document that divine control beliefs modify this association such that the curvilinear association is found primarily among individuals with low levels of divine control. By contrast, among those who more strongly endorse divine control, we observe no relationship between personal control and depression. We situate our findings in the differing and complicated perspectives on the implications of religious beliefs for psychological resources and well‐being.     

Prospective analysis of early lapse to drinking and smoking among individuals in concurrent alcohol and tobacco treatment

The aims of the current study were to examine, prospectively, (a) dynamic changes in affective state, self-efficacy, and urge in the hours before initial smoking and drinking lapses among individuals in concurrent alcohol and smoking treatment, and (b) the extent to which self-efficacy, urge to use, and/or the use of one substance predicted lapse to the other substance. Ninety-six men and women recruited for a clinical trial of concurrent alcohol and tobacco treatment were eligible for inclusion. Only data from those who experienced an initial lapse to drinking (n=29) or smoking (n=32) were included. Two outpatient substance abuse clinics provided concurrent alcohol and smoking treatment on a weekly basis for three months. Ecological Momentary Assessment (EMA) methods were employed over a 28-day monitoring period to assess antecedents to first drink, and a 14-day monitoring period was examined for initial smoking lapses. Baseline and EMA measures of positive and negative affect, alcohol/smoking urge, alcohol/smoking abstinence self-efficacy, nicotine withdrawal, and quantity/frequency of alcohol and tobacco use were examined as lapse predictors. Analyses of EMA ratings controlled for the corresponding baseline measure. Smoking lapse among individuals in concurrent alcohol and tobacco treatment was foreshadowed by higher urges to smoke, lower positive mood, and lower confidence to resist smoking. Drinking lapse was preceded by lower confidence to resist smoking, but only among individuals who reported recent smoking. Concurrent alcohol and smoking treatment should focus on the enhancement of abstinence self-efficacy, positive mood, and the curbing of urges in order to offset lapse risk.     

Specificity in rehabilitation of word production: a meta-analysis and a case study

Speech production impairment is a frequent deficit observed in aphasic patients and rehabilitation programs have been extensively developed. Nevertheless, there is still no agreement on the type of rehabilitation that yields the most successful outcomes. Here, we ran a detailed meta-analysis of 39 studies of word production rehabilitation involving 124 patients. We used a model-driven approach for analyzing each rehabilitation task by identifying which levels of our model each task tapped into. We found that (1) all rehabilitation tasks are not equally efficient and the most efficient ones involved the activation of the two levels of the word production system: the phonological output lexicon and the phonological output, and (2) the activation of the speech perception system as it occurs in many tasks used in rehabilitation is not successful in rehabilitating word production. In this meta-analysis, the effect of the activation of the phonological output lexicon and the phonological output cannot be assessed separately. We further conducted a rehabilitation study with DPI, a patient who suffers from a damage of the phonological output lexicon. Our results confirm that rehabilitation is more efficient, in terms of time and performance, when specifically addressing the impaired level of word production.