448 research outputs found

    Error in Monte Carlo, quasi-error in Quasi-Monte Carlo

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    While the Quasi-Monte Carlo method of numerical integration achieves smaller integration error than standard Monte Carlo, its use in particle physics phenomenology has been hindered by the abscence of a reliable way to estimate that error. The standard Monte Carlo error estimator relies on the assumption that the points are generated independently of each other and, therefore, fails to account for the error improvement advertised by the Quasi-Monte Carlo method. We advocate the construction of an estimator of stochastic nature, based on the ensemble of pointsets with a particular discrepancy value. We investigate the consequences of this choice and give some first empirical results on the suggested estimators.Comment: 41 pages, 19 figure

    Measuring Paranoid Beliefs in Adolescents:A Comparison of the Revised-Green et al.’s Paranoid Thoughts Scale (R-GPTS) and the Bird Checklist of Adolescent Paranoia (B-CAP)

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    Research on paranoid beliefs in adolescents is in its infancy. Valid and reliable assessments are essential to advancing the field, yet there is no current consensus as to which are optimal to use in this population. This study compared the psychometric properties of two measures of paranoia in a general population adolescent sample. A cross-sectional study with quota sampling (gender and age) recruited adolescents (14-17 years) from the UK (n=262) and USA (n=200), who completed the Revised Green et al. Paranoid Thoughts Scale (R-GPTS) and the Bird Checklist for Adolescent Paranoia (B-CAP). We assessed factor structures, intercorrelations, overlap of participants identified as at-risk for paranoid thoughts via both scales, convergent validity (scales with one another) and discriminant validity (distress, wellbeing, bullying and discrimination). Both scales performed equally well in terms of factorial validity. Intercorrelations between the subscales and with general distress were high for both measures. However, a substantial percentage of participants were identified as having paranoid beliefs according to the R-GPTS but not the B-CAP. Furthermore, the B-CAP showed a very high correlations (0.69≤r≤0.79) with self-reported bullying experiences, which bordered on multicollinearity. Findings highlight the possibility that B-CAP may risk confounding paranoid beliefs with exposure to bullying more so than R-GPTS, and that B-CAP may miss instances of elevated paranoia that are captured by the R-GPTS. Future research needs to further explore this by validating both scales with an external (e.g., interview-based) criterion for paranoia

    Cross-cultural validation of the Revised Green et al., Paranoid Thoughts Scale

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    Background. With efforts increasing worldwide to understand and treat paranoia, there is a pressing need for culturally valid assessments of paranoid beliefs. The recently developed Revised Green et al. Paranoid Thoughts Scale (R-GPTS) constitutes an easy to administer self-report assessment of mild ideas of reference and more severe persecutory thoughts. Moreover, it comes with clinical cut-offs for increased usability in research and clinical practice. With multiple translations of the R-GPTS already available and in use, a formal test of its measurement invariance is now needed.Methods. Using data from a multinational cross-sectional online survey in the UK, USA, Australia, Germany, and Hong Kong (N=2510), we performed confirmatory factory analyses on the R-GPTS and tested for measurement invariance across sites.Results. We found sufficient fit for the two-factor structure (ideas of reference, persecutory thoughts) of the R-GPTS across cultures. Measurement invariance was found for the persecutory thoughts subscale, indicating that it does measure the same construct across the tested samples in the same way. For ideas of reference, we found no scalar invariance, which was traced back to (mostly higher) item intercepts in the Hong Kong sample.Conclusion. We found sufficient invariance for the persecutory thoughts scale, which is of substantial practical importance, as it is used for the screening of clinical paranoia. A direct comparison of the ideas of reference sum-scores between cultures, however, may lead to an over-estimation of these milder forms of paranoia in some (non-western) cultures

    Pandemic Paranoia in the General Population:International Prevalence and Sociodemographic Profile

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    BACKGROUND: The term ‘pandemic paranoia’ has been coined to refer to heightened levels of mistrust and suspicion towards other people specifically due to the COVID-19 pandemic. In this study, we examine the international prevalence of pandemic paranoia in the general population and its associated sociodemographic profile. METHODS: A representative international sample of general population adults (N = 2510) from five sites (USA N = 535, Germany N = 516, UK N = 512, Australia N = 502 and Hong Kong N = 445) were recruited using stratified quota sampling (for age, sex, educational attainment) and completed the Pandemic Paranoia Scale (PPS). RESULTS: The overall prevalence rate of pandemic paranoia was 19%, and was highest in Australia and lowest in Germany. On the subscales of the PPS, prevalence was 11% for persecutory threat, 29% for paranoid conspiracy and 37% for interpersonal mistrust. Site and general paranoia significantly predicted pandemic paranoia. Sociodemographic variables (lower age, higher population size and income, being male, employed and no migrant status) explained additional variance and significantly improved prediction of pandemic paranoia. CONCLUSIONS: Pandemic paranoia was relatively common in a representative sample of the general population across five international sites. Sociodemographic variables explained a small but significant amount of the variance in pandemic paranoia

    RELATE-a randomised controlled feasibility trial of a Relating Therapy module for distressing auditory verbal hallucinations: a study protocol

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    Introduction Auditory verbal hallucinations (AVHs) are associated with distress and reduced functioning. Research suggests that distress is associated with the voice hearer's responding to AVH in a passive and subordinate manner. A novel approach focuses on relating to AVH and teaches assertive responses to AVH using experiential role-plays. A small pilot study found a large effect of this approach on AVH distress but an independent multicentre study is required to ascertain effectiveness across different settings. We aim to estimate the expected effect for a subsequent trial to demonstrate that adding a module of Relating Therapy (RT) to treatment as usual (TAU) is superior to TAU alone in reducing AVH distress. We also test the feasibility of patient recruitment, therapist training, and therapy monitoring in different psychological and psychiatric outpatient facilities in Germany. Methods and analysis We will recruit 75 patients diagnosed with a schizophrenia spectrum disorder and persistent distressing AVH across four sites. Patients will be randomised to receive either 16 sessions of RT plus TAU or TAU alone within a 5-month period. Randomisation will be stratified by sites. Single-blind assessments will take place at baseline, at 5 months (T1) and at 9 months (T2). The primary outcome is the distress factor score of the AVH subscale of the Psychotic Symptoms Rating Scale at T2 adjusted for the baseline value. Secondary outcomes are change in depressive symptoms, quality of life, time spent in structured activities as well as negative relating to voices and to other people. Ethics and dissemination The trial has received ethical approval from the German Psychological Society Ethics Committee. The trial results will be disseminated through conference presentations, peer-reviewed publications and social media
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