1,296 research outputs found
How to Couple from the Past Using a Read-Once Source of Randomness
We give a new method for generating perfectly random samples from the
stationary distribution of a Markov chain. The method is related to coupling
from the past (CFTP), but only runs the Markov chain forwards in time, and
never restarts it at previous times in the past. The method is also related to
an idea known as PASTA (Poisson arrivals see time averages) in the operations
research literature. Because the new algorithm can be run using a read-once
stream of randomness, we call it read-once CFTP. The memory and time
requirements of read-once CFTP are on par with the requirements of the usual
form of CFTP, and for a variety of applications the requirements may be
noticeably less. Some perfect sampling algorithms for point processes are based
on an extension of CFTP known as coupling into and from the past; for
completeness, we give a read-once version of coupling into and from the past,
but it remains unpractical. For these point process applications, we give an
alternative coupling method with which read-once CFTP may be efficiently used.Comment: 28 pages, 2 figure
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Non-verbal communication in meetings of psychiatrists and patients with schizophrenia
Objective
Recent evidence found that patients with schizophrenia display non‐verbal behaviour designed to avoid social engagement during the opening moments of their meetings with psychiatrists. This study aimed to replicate, and build on, this finding, assessing the non‐verbal behaviour of patients and psychiatrists during meetings, exploring changes over time and its association with patients' symptoms and the quality of the therapeutic relationship.
Method
40‐videotaped routine out‐patient consultations, involving patients with schizophrenia, were analysed. Non‐verbal behaviour of patients and psychiatrists was assessed during three fixed, 2‐min intervals using a modified Ethological Coding System for Interviews. Symptoms, satisfaction with communication and the quality of the therapeutic relationship were also measured.
Results
Over time, patients' non‐verbal behaviour remained stable, whilst psychiatrists' flight behaviour decreased. Patients formed two groups based on their non‐verbal profiles, one group (n = 25) displaying pro‐social behaviour, inviting interaction and a second (n = 15) displaying flight behaviour, avoiding interaction. Psychiatrists interacting with pro‐social patients displayed more pro‐social behaviours (P < 0.001). Patients' pro‐social profile was associated reduced symptom severity (P < 0.05), greater satisfaction with communication (P < 0.001) and positive therapeutic relationships (P < 0.05).
Conclusion
Patients' non‐verbal behaviour during routine psychiatric consultations remains unchanged, and is linked to both their psychiatrist's non‐verbal behaviour and the quality of the therapeutic relationship
Association of treatment satisfaction and psychopathological sub-syndromes among involuntary patients with psychotic disorders
Publisher's version: http://www.springerlink.com/content/rx24036274667t10
Are Group Psychotherapeutic Treatments Effective for Patients with Schizophrenia? A Systematic Review and Meta-Analysis
<b><i>Background:</i></b> Different psychotherapeutic treatments for schizophrenia are delivered in groups. However, little is known about the effectiveness of these group therapies for people with schizophrenia across different treatments with varying therapeutic orientations. This review aimed to (1) estimate the effect of different group psychotherapeutic treatments for schizophrenia and (2) explore whether any overall ‘group effect' is moderated by treatment intensity, diagnostic homogeneity and therapeutic orientation. <b><i>Methods:</i></b> A systematic search of randomised controlled trials exploring the effectiveness of group psychotherapeutic treatments for people with schizophrenia was conducted. Random-effect meta-analyses on endpoint symptom scores compared group psychotherapeutic treatments with treatment as usual and active sham groups. Findings on social functioning were described narratively, and meta-regression analyses on group characteristics were carried out. <b><i>Results:</i></b> Thirty-four eligible trials were included. A weak-to-moderate significant between-group difference in favour of group psychotherapeutic treatments was found for negative symptom scores (standard mean difference = -0.37, 95% confidence interval -0.60, -0.14; p < 0.01, I<sup>2</sup> = 59.8%) only when compared to treatment as usual and not to active sham groups. Improved social functioning was reported as a treatment outcome in the majority of studies compared to treatment as usual. The ‘group effect' on negative symptoms was positively related to ‘treatment intensity' (β = 0.32, standard error = 0.121; p < 0.05). <b><i>Conclusion:</i></b> Group psychotherapeutic treatments can improve negative symptoms and social functioning deficits in the treatment of schizophrenia. The effect occurs across different treatments and appears to be non-specific. Future research should identify the underlying mechanisms for the positive effect of participating in groups and explore how they can be maximised to increase the therapeutic benefit.</jats:p
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