Diffusion model analysis with MATLAB: A DMAT primer

The Ratcliff diffusion model has proved to be a useful tool in reaction time analysis. However, its use has been limited by the practical difficulty of estimating the parameters. We present a software tool, the Diffusion Model Analysis Toolbox (DMAT), intended to make the Ratcliff diffusion model for reaction time and accuracy data more accessible to experimental psychologists. The tool takes the form of a MATLAB toolbox and can be freely downloaded from ppw.kuleuven.be/okp/dmatoolbox. Using the program does not require a background in mathematics, nor any advanced programming experience (but familiarity with MATLAB is useful). We demonstrate the basic use of DMAT with two examples.     

Safeguarding Tradition: Psychological Type Preferences of Male Vergers in the Church of England

The current study explores the psychological type profile of vergers within the Church of England. A sample of 42 male vergers completed the Myers-Briggs Type Indicator (Form G). The study shows that vergers tend to prefer introversion over extraversion, sensing over intuition, thinking over feeling, and judging over perceiving. The type preferences of vergers are compared and contrasted with the type preferences of clergy and laity. These findings are explored within the context of the role of the verger within the Church of England.     

Stimulus preference assessments and the utility of a moderate category

Recent studies have shown that moderate (Piazza, Fisher, Hagopian, Bowman, & Toole, 1996 ) and low (Taravella, Lerman, Contrucci, & Roane, 2000 ) ranked items on stimulus preference assessments may function as reinforcers. Following an initial preference assessment the current study analyzed whether moderate or low preference items were more likely to be ranked as high preference on subsequent preference assessments. Results show that for five of the seven participants additional high preference items were identified from the moderate preference set, while additional high preference items were identified from the low preference set for only one participant. Results are discussed in terms of the need to identify multiple reinforcers and the composition of the stimulus array during preference assessment. Copyright © 2006 John Wiley & Sons, Ltd.     

A revised semantic differential scale distinguishing between negative and positive God images

A sample of 755 school pupils between the ages of 11 and 18 years completed the Benson and Spilka semantic differential measure of God images. Factor analysis indicated the advantages of re‐scoring the measure as an eight item unidimensional index, defining semantic space relating to God images ranging from negative affect to positive affect.     

Gender Differences in Campaign Materials and Politicians’ Professional Orientation: The Case of a Hong Kong Election

This study examines gender differences in election campaigns with a specific focus on whether professional orientation, defined as the extent to which a politician sees politics as a career with its own ladder of advancement, would suppress gender differences. This is because candidates with higher levels of professional orientation may tend to see themselves primarily as “politicians” instead of as women or men. A content analysis of 836 candidates’ campaign leaflets in a local level election in Hong Kong was conducted. The results show some differences in the extent to which women and men candidates mentioned certain issues and used certain appeals in their platforms. However, when gender differences existed, they were more pronounced among candidates with weaker professional orientation.     

Kidnapping: a criminal profile of persons convicted 1979-2001

Kidnapping has been a neglected crime in criminological research. In fact, there has been a dramatic increase in the yearly numbers of police recorded kidnapping offences in England and Wales in the last 25 years, but this has not been matched by a similar increase in convictions. This study focuses on the official criminal histories of the 7042 males and 545 females who were convicted at least once for kidnapping between 1979 and 2001. Of these, 3.9% of the males and 2.6% of the females had convictions for kidnapping on more than one occasion.We examined two subgroups to ensure long observation periods for prior and subsequent convictions. Of those convicted of kidnapping in 2001, around one-half (51.1%) of the males and around one-third (36.6%) of the females had previous convictions. The previous convictions consist of a wide range of offences, with the most common being theft and violent offences. A 20-year follow-up of those convicted in 1979-81 showed that three in five males and one in three females are subsequently convicted on at least one more occasion for a standard-list offence.An examination of convictions for other offences brought to court at the same time as the kidnap offence enabled a typology of kidnaps to be proposed. Those kidnaps with co-convictions of an acquisitive nature declined over the period, whereas other types, including sexual and violent, showed rises. Changing shifts in the nature of kidnaps have important policy implications.     

The relationship between psychological type and the three major dimensions of personality

Five hundred and fifty-four undergraduate students attending a university-sector college in South Wales, United Kingdom, completed the Myers-Briggs Type Indicator (MBTI) (Form G) and the short-form Revised Eysenck Personality Questionnaire. The results showed a number of statistically significant relationships between the two models of personality and drew attention to two substantively significant relationships. In Eysenckian terms, the Myers-Briggs Type Indicator constructs of introversion and extraversion translated as “neurotic introversion” and as “stable extraversion.” The Myers-Briggs Type Indicator constructs of judging and perceiving translated as “low psychoticism” and “high psychoticism”. Based on their interpretation of findings, the authors argue that the MBTI and the Eysenckian models should be viewed as interacting in a dynamic and informative fashion, not as unrelated, totally disparate models.     

Long‐term stability of edible preferences in individuals with developmental disabilities

Multiple stimulus without replacement (MSWO) preference assessments were used to examine the stability of preference hierarchies in eight individuals with developmental disabilities. In Study 1, preference assessments using edible items were conducted 6 months apart; in Study 2, assessments were conducted 12 months apart. As in previous studies analyzing preference stability, individual differences in stability were found in both studies. However, mean rank order coefficients across participants revealed interesting findings in both comparisons. Generally, preference for edible items, particularly the most and least preferred stimuli, was more stable across time than has been found in other research conducted with leisure items. Stability was greater when only 6 months lapsed between assessments. Moreover, for three of the eight participants, rank order coefficients were significant across both studies indicating the possibility that some individuals may tend toward more stable preferences. Copyright © 2007 John Wiley & Sons, Ltd.     

What breaks a leader: the curvilinear relation between assertiveness and leadership

The authors propose that individual differences in assertiveness play a critical role in perceptions about leaders. In contrast to prior work that focused on linear effects, the authors argue that individuals seen either as markedly low in assertiveness or as high in assertiveness are generally appraised as less effective leaders. Moreover, the authors claim that observers' perceptions of leaders as having too much or too little assertiveness are widespread. The authors linked the curvilinear effects of assertiveness to underlying tradeoffs between social outcomes (a high level of assertiveness worsens relationships) and instrumental outcomes (a low level of assertiveness limits goal achievement). In 3 studies, the authors used qualitative and quantitative approaches and found support for their account. The results suggest that assertiveness (and other constructs with nonlinear effects) might have been overlooked in research that has been focused on identifying what makes a leader rather than on identifying what breaks a leader.