http://repub.eur.nl/res/aut/10395/ List of Publications en http://repub.eur.nl/static-eur/img/logo.png http://repub.eur.nl http://repub.eur.nl/res/pub/39962/ 2013-04-01T00:00:00Z There is both theoretical ground and empirical evidence to suggest that nonidentifications in police line-ups are diagnostic of the suspect's innocence. However, it is frequently assumed that both laypeople and legal decision makers fail to appreciate this diagnosticity. It is hypothesized that this underestimation is fuelled by a general reluctance to accept null findings. To test this idea, participants judged the importance of nonidentifications and foil identifications. As predicted, foil identifications were considered to have more diagnostic power than nonidentifications (Study 1). In Studies 2 and 3, the hypothesis was tested that nonidentifications intuitively generate more uncertainty than suspect and foil identifications. This hypothesis was confirmed in that participants were able to conjure up more alternative explanations for nonidentifications compared to suspect and foil identifications. Findings are discussed in the light of what can be called presence bias. http://repub.eur.nl/res/pub/23791/ 2010-10-01T00:00:00Z People involved in criminal proceedings (e.g. police officers, district attorneys, judges, and jury members) may run the risk of developing confirmation bias, or tunnel vision. That is, these parties may readily become convinced that the suspect is guilty, and may then no longer be open to alternative scenarios in which the suspect is actually innocent. This may be reflected in a preference for guilt-confirming investigation endeavours, as opposed to investigations that are aimed at confirming, or even excluding, alternative scenarios. In three studies, participants read a case file, and were subsequently instructed to select additional police investigations. Some of these additional endeavours were guilt-confirming (i.e. incriminating), whereas others were disconfirming (i.e. exonerating). Results suggest that additional investigation search was guided by an initial assessment of the suspect's guilt (Study 1). Furthermore, participants' tendency to select incriminating investigations increased with increased crime severity, and with the strength of the evidence present in the case file. Finally, the selection of incriminating investigations was associated with conviction rates (Study 3). However, in general, participants did not favour incriminating endeavours. That is, in the three studies, the percentages of selected incriminating endeavours did hardly or not exceed 50%. http://repub.eur.nl/res/pub/23073/ 2010-05-01T00:00:00Z Abstract The aim of this study was to gain more insight in the backgrounds and characteristics of arsonists. For this, the psychiatric, psychological, personal, and criminal backgrounds of all arsonists (n=25), sentenced to forced treatment in the maximum security forensic hospital "De Kijvelanden", were compared to the characteristics of a control group of patients (n=50), incarcerated at the same institution for other severe crimes. Apart from DSM-IV Axis I and Axis II disorders, family backgrounds, level of education, treatment history, intelligence (WAIS scores), and PCL-R scores were included in the comparisons. Furthermore, the apparent motives for the arson offences were explored. It was found that arsonists had more often received psychiatric treatment, prior to committing their index offence, and had a history of severe alcohol abuse more often in comparison to the controls. The arsonists turned out to be less likely to suffer from a major psychotic disorder. Both groups did not differ significantly on the other variables, among which the PCL-R total scores and factor scores. Exploratory analyses however, did suggest that arsonists may differentiate from non-arsonists on three items of the PCL-R, namely impulsivity (higher scores), superficial charm (lower scores), and juvenile delinquency (lower scores). Although the number of arsonists with a major psychotic disorder was relatively low (28%), delusional thinking of some form was judged to play a role in causing arson crimes in about half of the cases (52%). http://repub.eur.nl/res/pub/17463/ 2009-05-01T00:00:00Z According to public opinion, members of shooting organizations (i.e. shooters) are thought to be more aggressive than other groups in society. Also, guns are generally seen as stimuli that elicit aggressive behaviour. The present study examined whether shooters are really more aggressive than non-shooters. Shooters and non-shooters were compared on measures of aggressive behaviour, aggressive fantasies, impulsivity, and main personality dimensions (i.e. neuroticism, psychoticism, and extraversion). The results showed that members of shooting associations were less aggressive and impulsive than non-members, even when controlling for their tendency to present themselves in a more favourable manner. These findings suggest that there is no reason to consider hobby shooters a priori as more aggressive. A possible explanation could be that for shooters, their positively coloured experiences with guns have changed the aggression eliciting effect that normally occurs when interacting with guns (i.e. the weapons effect). These findings are discussed in light of the cognitive script theory of aggression by Huesmann. http://repub.eur.nl/res/pub/18343/ 2009-03-01T00:00:00Z The present study made an attempt to induce fear-related reasoning biases by providing children with negative information about a novel stimulus. For this purpose, non-clinical children aged 9-12 years (N = 318) were shown a picture of an unknown animal for which they received either negative, ambiguous, positive, or no information. Then children completed a series of tests for measuring various types of reasoning biases (i.e., confirmation bias and covariation bias) in relation to this animal. Results indicated that children in the negative and, to a lesser extent, the ambiguous information groups displayed higher scores on tests of fear-related reasoning biases than children in the positive and no information groups. Altogether, these results support the idea that learning via negatively tinted information plays a role in the development of fear-related cognitive distortions in youths. http://repub.eur.nl/res/pub/11976/ 2008-03-14T00:00:00Z Rede, in verkorte vorm uitgesproken ter gelegenheid van het aanvaarden van het ambt van bijzonder hoogleraar Rechtspsychologie aan de Erasmus Universiteit Rotterdam vanwege het Trustfonds EUR op 14 maart 2008. Juristen maken regelmatig gebruik van psychologische inzichten. Zo vraagt de rechter aan gedragswetenschappelijk deskundigen of een verdachte toerekeningsvatbaar is en of een getuigenverklaring geloofwaardig is. Toch kunnen ze dat soms maar beter niet doen, aldus prof.mr.dr. Eric Rassin. http://repub.eur.nl/res/pub/1898/ 2004-01-01T00:00:00Z This study investigated (1) the usefulness of the thought suppression paradigm in understanding impulsivity and aggression and (2) the relation between intrusions, suppression and other control strategies on the one hand, and psychopathology on the other. Ninety undergraduate students filled in the White Bear Suppression Inventory (WBSI), the Thought Control Questionnaire (TCQ), the Minnesota Multiphasic Personality Inventory-2 (MMPI-2), five traits from the Eysenck Personality Profiler (EPP), and the Barratt Impulsivity Scale (BIS). No relationship between intrusion and suppression, and impulsivity was found. However, significant correlations between intrusion and aggression were found. Intrusion, suppression, self-punishment, and psychopathology were all correlated positively. Implications of these findings for the dynamics between intrusion, thought control, and aggression are discussed. http://repub.eur.nl/res/pub/2866/ 2001-04-05T00:00:00Z Thought-action fusion (TAF) refers to a set of cognitive biases that are thought to play a role in the development of obsessional phenomena. To measure these biases, R. Shafran, D. S. Thordarson, and S. Rachman (1996; Journal of Anxiety Disorders, 10, 379–391) developed the TAF-scale. They concluded that the TAF-scale possesses adequate psychometric qualities. The current study sought to further explore the reliability and validity of the TAF-scale. Results indicate that the TAF-scale has good internal consistency. TAF-scores correlated with self-reports of obsessional problems. Furthermore, mean scores in a mixed sample of anxiety disordered patients were higher than those in a normal sample. However, temporal consistency was somewhat disappointing. Also, the question remains whether TAF is specific to obsessive–compulsive disorder or taps more pervasive biases that play a role in a variety of disorders. http://repub.eur.nl/res/pub/2878/ 2000-11-01T00:00:00Z The Eysenck Personality Profiler (EPP) is a questionnaire measuring 21 primary personality traits that are thought to constitute the three supertraits of Extraversion, Neuroticism and Psychoticism. The present study examined the reliability, factor structure and convergent validity of the Dutch translation of the EPP in a sample of introductory psychology students (N=215). Results indicate that the internal consistency of most EPP scales was satisfactory. Furthermore, exploratory and confirmatory factor analyses showed that the to-be-expected three-factor structure provided a reasonable fit for EPP data. Finally, Extraversion, Neuroticism and Psychoticism were found to correlate in a meaningful way with the "big 5" supertraits as indexed by the Five-Factor Personality Inventory. http://repub.eur.nl/res/pub/2881/ 2000-09-01T00:00:00Z Research has shown that there are strong similarities in content between the obsessions and compulsions that characterize obsessive–compulsive disorder and nonclinical obsessions and compulsions. However, clinical and nonclinical obsessions and compulsions do differ with respect to characteristics like frequency, intensity, discomfort and elicited resistance. Two separate concepts have been invoked to explain how normal obsessions and compulsions may develop into clinical phenomena. First, it is suggested that thought–action fusion (TAF) contributes to obsessive–compulsive symptoms. Second, thought suppression may intensify obsessive–compulsive symptoms due to its paradoxical effect on intrusive thoughts. Although both phenomena have been found to contribute to obsessive–compulsive symptoms, possible interactions between these two have never been investigated. The current study explored how TAF and thought suppression interact in the development of obsessive–compulsive symptoms. Undergraduate psychology students (N=173) completed questionnaires pertaining to TAF, thought suppression and obsessive–compulsive symptoms. Covariances between the scores on these questionnaires were analyzed by means of structural equation modeling. Results suggest that TAF triggers thought suppression, while thought suppression, in turn, promotes obsessive–compulsive symptoms. http://repub.eur.nl/res/pub/2882/ 2000-01-01T00:00:00Z In onderzoek is gebleken dat klinische obsessies en compulsies inhoudelijk niet verschillen van alledaagse intrusies en rituelen. De verschillen tussen beide betreffen veeleer kenmerken als frequentie, ervaren weerzin en opgeroepen weerstand. De verklaring van dergelijke verschillen in afwezigheid van een inhoudelijk onderscheid lijkt vooral te zijn gelegen in twee psychologische fenomenen. Ten eerste wordt verondersteld dat overdreven interpretaties van intrusies (samen te vatten in het concept thought-action fusion [taf]) leiden tot intensivering van obsessieve-compulsieve symptomen. Op de tweede plaats lijkt gedachtenonderdrukking (suppressie) te resulteren in meer, in plaats van minder, obsessieve-compulsieve symptomen. De potentiële interacties tussen taf en suppressie zijn nog niet in kaart gebracht. In het huidige onderzoek werd een poging ondernomen om te achterhalen of en op welke manier taf en suppressie samengaan in de ontwikkeling van obsessieve-compulsieve symptomen. Daartoe vulde een groep studenten (N = 173) verschillende vragenlijsten in. De data werden geanalyseerd met behulp van structural equation modelling. Uit de analyse volgde grosso modo dat taf aanleiding geeft tot suppressie, terwijl suppressie vervolgens leidt tot obsessieve-compulsieve symptomen.