13,238 research outputs found
A computerized test of speed of language comprehension unconfounded by literacy
A computerised version of the Silly Sentences task developed for use with children
(Baddeley et al, 1995) is found to be equivalent to the pencil-and-paper version from the
SCOLP Test (Baddeley et al, 1992) with UK undergraduates, and is usable by a sample of
young UK children. Because the sentences are presented aloud instead of being written, the
computerised test is not affected by literacy skills. Translated into Kiswahili, the task was
used in Tanzanian schools, despite the absence of an electricity supply and a very different
cultural background. The decision latencies had a test-retest reliability of 0.69 over 5
months, and were independent of age and baseline decision speed. The task appears
appropriate for longitudinal studies, including those in developing countries. Given its
simplicity and the correlations with the original SCOLP version of the task, it may also
be useful in studies on literate adults
Residuals and goodness-of-fit tests for stationary marked Gibbs point processes
The inspection of residuals is a fundamental step to investigate the quality
of adjustment of a parametric model to data. For spatial point processes, the
concept of residuals has been recently proposed by Baddeley et al. (2005) as an
empirical counterpart of the {\it Campbell equilibrium} equation for marked
Gibbs point processes. The present paper focuses on stationary marked Gibbs
point processes and deals with asymptotic properties of residuals for such
processes. In particular, the consistency and the asymptotic normality are
obtained for a wide class of residuals including the classical ones (raw
residuals, inverse residuals, Pearson residuals). Based on these asymptotic
results, we define goodness-of-fit tests with Type-I error theoretically
controlled. One of these tests constitutes an extension of the quadrat counting
test widely used to test the null hypothesis of a homogeneous Poisson point
process
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Social Influence and Individual Difference in Experimental Juries
In a jury decision-making, individuals must compromise in order to reach a group consensus. If individuals compromise for non-rational reasons, such as a preference for conformity or due to erroneous information, then the final decision of the group may be biased. This paper presents original experimental data which shows that groups do have a significant tendency to compromise in jury-like settings. Econometric evidence also shows that features of groups, including the generosity of the group overall, will dictate the extent of compromise. The data also reveal that individual traits such as gender and capacity for empathy are associated with the extent of compromise in a jury-type setting. The implications are that interactions between individual and group characteristics limit the objectivity of decision-making
An architecturally constrained model of random number generation and its application to modeling the effect of generation rate
Random number generation (RNG) is a complex cognitive task for human subjects, requiring deliberative control to avoid production of habitual, stereotyped sequences. Under various manipulations (e.g., speeded responding, transcranial magnetic stimulation, or neurological damage) the performance of human subjects deteriorates, as reflected in a number of qualitatively distinct, dissociable biases. For example, the intrusion of stereotyped behavior (e.g., counting) increases at faster rates of generation. Theoretical accounts of the task postulate that it requires the integrated operation of multiple, computationally heterogeneous cognitive control (âexecutiveâ) processes. We present a computational model of RNG, within the framework of a novel, neuropsychologically-inspired cognitive architecture, ESPro. Manipulating the rate of sequence generation in the model reproduced a number of key effects observed in empirical studies, including increasing sequence stereotypy at faster rates. Within the model, this was due to time limitations on the interaction of supervisory control processes, namely, task setting, proposal of responses, monitoring, and response inhibition. The model thus supports the fractionation of executive function into multiple, computationally heterogeneous processes
Score, Pseudo-Score and Residual Diagnostics for Spatial Point Process Models
We develop new tools for formal inference and informal model validation in
the analysis of spatial point pattern data. The score test is generalized to a
"pseudo-score" test derived from Besag's pseudo-likelihood, and to a class of
diagnostics based on point process residuals. The results lend theoretical
support to the established practice of using functional summary statistics,
such as Ripley's -function, when testing for complete spatial randomness;
and they provide new tools such as the compensator of the -function for
testing other fitted models. The results also support localization methods such
as the scan statistic and smoothed residual plots. Software for computing the
diagnostics is provided.Comment: Published in at http://dx.doi.org/10.1214/11-STS367 the Statistical
Science (http://www.imstat.org/sts/) by the Institute of Mathematical
Statistics (http://www.imstat.org
Transitive simple subgroups of wreath products in product action
A transitive simple subgroup of a finite symmetric group is very rarely
contained in a full wreath product in product action. All such simple
permutation groups are determined in this paper. This remarkable conclusion is
reached after a definition and detailed examination of `Cartesian
decompositions' of the permuted set, relating them to certain `Cartesian
systemsof subgroups'. These concepts, and the bijective connections between
them, are explored in greater generality, with specific future applications in
mind.Comment: Submitte
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