ANOVA and the variance homogeneity assumption: Exploring a better gatekeeper

Valid use of the traditional independent samples ANOVA procedure requires that the population variances are equal. Previous research has investigated whether variance homogeneity tests, such as Levene's test, are satisfactory as gatekeepers for identifying when to use or not to use the ANOVA procedure. This research focuses on a novel homogeneity of variance test that incorporates an equivalence testing approach. Instead of testing the null hypothesis that the variances are equal against an alternative hypothesis that the variances are not equal, the equivalence-based test evaluates the null hypothesis that the difference in the variances falls outside or on the border of a predetermined interval against an alternative hypothesis that the difference in the variances falls within the predetermined interval. Thus, with the equivalence-based procedure, the alternative hypothesis is aligned with the research hypothesis (variance equality). A simulation study demonstrated that the equivalence-based test of population variance homogeneity is a better gatekeeper for the ANOVA than traditional homogeneity of variance tests.     

Psychological ownership: The implicit association between self and already-owned versus newly-owned objects

Evidence from explicit measures (e.g. favourability ratings, valuations) has led to the prevalent hypothesis that owned objects become cognitively associated with self-concept. Using a novel version of the Implicit Association Test (self-object IAT), wherein participants categorized objects by colour, we evaluated implicit cognitive associations involving self with already-owned and newly-owned objects. We observed faster responses when self-related words required the same response key as the colour that incidentally corresponded to self-owned objects, irrespective of length of ownership. These findings suggest that participants efficiently form cognitive associations between self and self-owned objects within mere minutes of ownership induction and inspire questions about the extent to which length of ownership drives the strength of this association.     

Exploring the perceptual biases associated with believing and disbelieving in paranormal phenomena

Ninety-five participants (32 believers, 30 disbelievers and 33 neutral believers in the paranormal) participated in an experiment comprising one visual and one auditory block of trials. Each block included one ESP, two degraded stimuli and one random trial. Each trial included 8 screens or epochs of “random” noise. Participants entered a guess if they perceived a stimulus or changed their mind about stimulus identity, rated guesses for confidence and made notes during each trial. Believers and disbelievers did not differ in the number of guesses made, or in their ability to detect degraded stimuli. Believers displayed a trend toward making faster guesses for some conditions and significantly higher confidence and more misidentifications concerning guesses than disbelievers. Guesses, misidentifications and faster response latencies were generally more likely in the visual than auditory conditions. ESP performance was no different from chance. ESP performance did not differ between belief groups or sensory modalities.     

Answer Similarity Analysis at the Group Level

Answer similarity indices were developed to detect pairs of test takers who may have worked together on an exam or instances in which one test taker copied from another. For any pair of test takers, an answer similarity index can be used to estimate the probability that the pair would exhibit the observed response similarity or a greater degree of similarity under the assumption that the test takers worked independently. To identify groups of test takers with unusually similar response patterns, Wollack and Maynes suggested conducting cluster analysis using probabilities obtained from an answer similarity index as measures of distance. However, interpretation of results at the cluster level can be challenging because the method is sensitive to the choice of clustering procedure and only enables probabilistic statements about pairwise relationships. This article addresses these challenges by presenting a statistical test that can be applied to clusters of examinees rather than pairs. The method is illustrated with both simulated and real data.     

A RUNS‐TEST ALGORITHM: CONTINGENT REINFORCEMENT AND RESPONSE RUN STRUCTURES

Four rats' choices between two levers were differentially reinforced using a runs‐test algorithm. On each trial, a runs‐test score was calculated based on the last 20 choices. In Experiment 1, the onset of stimulus lights cued when the runs score was smaller than criterion. Following cuing, the correct choice was occasionally reinforced with food, and the incorrect choice resulted in a blackout. Results indicated that this contingency reduced sequential dependencies among successive choice responses. With one exception, subjects' choice rule was well described as biased coin flipping. In Experiment 2, cuing was removed and the reinforcement criterion was changed to a percentile score based on the last 20 reinforced responses. The results replicated those of Experiment 1 in successfully eliminating first‐order dependencies in all subjects. For 2 subjects, choice allocation was approximately consistent with nonbiased coin flipping. These results suggest that sequential dependencies may be a function of reinforcement contingency.     

The language of implicit preferences

Are attitudes affected by the language in which they are expressed? In particular, do individual preferences shift to accord with the cultural values embedded in a given language? To examine these questions, two experiments tested bilingual participants, administering the same test of implicit attitudes in two languages. In both studies, participants manifested attitudes that favored social categories associated with the test language, e.g. more pro-Moroccan attitudes when tested in Arabic as compared with French (Study 1) and more pro-Spanish attitudes when tested in Spanish as compared with English (Study 2). The effects of language on elicited preference were large (mean d > .7), providing evidence that preferences are not merely transmitted through language but also shaped by it.     

A nonparametric method to analyze interactions: The adjusted rank transform test

Experimental social psychologists routinely rely on ANOVA to study interactions between factors even when the assumptions underlying the use of parametric tests are not met. Alternative nonparametric methods are often relatively difficult to conduct, have seldom been presented into detail in regular curriculum and have the reputation - sometimes incorrectly - of being less powerful than parametric tests. This article presents the adjusted rank transform test (ART); a nonparametric test, easy to conduct, having the advantage of being much more powerful than parametric tests when certain assumptions underlying the use of these tests are violated. To specify the conditions under which the adjusted rank transform test is superior to the usual parametric tests, results of a Monte Carlo simulation are presented.     

What do you think of followers? Examining the content,structure, and consequences of implicit followership theories

Implicit followership theories (IFTs) are defined as individuals’ personal assumptions about the traits and behaviors that characterize followers. Goals of this research were to: (1) Identify the content and structure of IFTs, (2) examine the relationship between IFTs and extant implicit theories in the leadership literature, and (3) establish a preliminary nomological network of leaders’ implicit followership theories by examining its consequences for leader–follower interpersonal outcomes. This study included 1362 participants across five separate studies and seven samples. Results provide evidence for content, convergent, discriminant, criterion, and incremental validity, as well as internal and temporal consistency of the IFTs instrument. IFTs are represented by a first-order structure (Industry, Enthusiasm, Good Citizen, Conformity, Insubordination, and Incompetence), and a second-order structure (Followership Prototype and Antiprototype). Leaders’ IFTs predicted interpersonal outcomes: liking, relationship quality, trust, and job satisfaction. Future research and practical implications are discussed for this understudied branch of leadership research.     

合理应用运动平板试验与冠脉CT诊断冠心病临床策略分析

本文针对临床诊断冠心病的两种常用手段即运动平板试验和冠脉CT进行分析,鉴于目前临床普遍存在重视采用冠脉CT,甚至达到滥用的地步,而逐渐忽视平板运动试验的现象,紧密结合临床,客观分析两者的特点,阐述各自优缺点。希冀通过本文以帮助临床医师正确选择应用,避免偏颇,最终达到将两者有机的结合,真正适合临床需要,提高冠心病患者的检出率,有利于更好地对冠心病进行二级预防。     

The structure of vocational interests in Germany: Different methodologies, different conclusions

The cross-cultural generalizability of vocational interest structures has received significant attention in recent years. This article adds to this research in four respects. First, data from a context that has not previously been investigated (Germany) was analyzed. Second, students at different stages of their educational career were examined. Third, the interest structure in male and females was compared. Fourth, two methods—the randomization test of hypothesized order relations (RTOR) and confirmatory factor analysis (CFA)—were applied to three competing structural conceptions: Holland’s circular representation, Gati’s hierarchical model, and Rounds and Tracey’s alternative hierarchical model. RTOR supported all three representations, whereas CFA supported only Holland’s model. CFAs indicated that the interest structure is reasonably invariant between high school and university students, but that the configurations for high school females and males differ. Substantive and methodological implications are discussed.