1,040 research outputs found
The effect of the handwriting without tears program on student cursive writing achievement at Central Institute for the Deaf (CID)
Handwriting Without Tears (HWT) is a multi-sensory program that provides a simpler approach to the instruction of cursive handwriting. It was administered to a sample of third graders to assess the effectiveness of the program and determine if it would be a viable option for handwriting instruction at CID
The relationship between the Jacobi and the successive overrelaxation (SOR) matrices of a k-cyclic matrix
AbstractLet A be a (k−l, l)-generalized consistently ordered matrix with T and Lω its associated Jacobi and SOR matrices whose eigenvalues μ and λ satisfy the well-known relationship (λ+ω−1)k=ωkμkλk−1. For a subclass of the above matrices A we prove that the matrix analogue of the previous relationship holds. Exploiting the matrix relationship we show that the SOR method is equivalent to a certain monoparametric k-step iterative one when used for the solution of the fixed-point problem x=Tx+c
Spatial Mixing and Non-local Markov chains
We consider spin systems with nearest-neighbor interactions on an -vertex
-dimensional cube of the integer lattice graph . We study the
effects that exponential decay with distance of spin correlations, specifically
the strong spatial mixing condition (SSM), has on the rate of convergence to
equilibrium distribution of non-local Markov chains. We prove that SSM implies
mixing of a block dynamics whose steps can be implemented
efficiently. We then develop a methodology, consisting of several new
comparison inequalities concerning various block dynamics, that allow us to
extend this result to other non-local dynamics. As a first application of our
method we prove that, if SSM holds, then the relaxation time (i.e., the inverse
spectral gap) of general block dynamics is , where is the number of
blocks. A second application of our technology concerns the Swendsen-Wang
dynamics for the ferromagnetic Ising and Potts models. We show that SSM implies
an bound for the relaxation time. As a by-product of this implication we
observe that the relaxation time of the Swendsen-Wang dynamics in square boxes
of is throughout the subcritical regime of the -state
Potts model, for all . We also prove that for monotone spin systems
SSM implies that the mixing time of systematic scan dynamics is . Systematic scan dynamics are widely employed in practice but have
proved hard to analyze. Our proofs use a variety of techniques for the analysis
of Markov chains including coupling, functional analysis and linear algebra
Assimilation of radar altimeter data in numerical wave models: an impact study in two different wave climate regions
An operational assimilation system incorporating significant wave height observations in high resolution numerical wave models is studied and evaluated. In particular, altimeter satellite data provided by the European Space Agency (ESA-ENVISAT) are assimilated in the wave model WAM which operates in two different wave climate areas: the Mediterranean Sea and the Indian Ocean. The first is a wind-sea dominated area while in the second, swell is the principal part of the sea state, a fact that seriously affects the performance of the assimilation scheme. A detailed study of the different impact is presented and the resulting forecasts are evaluated against available buoy and satellite observations. The corresponding results show a considerable improvement in wave forecasting for the Indian Ocean while in the Mediterranean Sea the assimilation impact is restricted to isolated areas
Lee-yang zeros and the complexity of the ferromagnetic ising model on bounded-degree graphs
We study the computational complexity of approximating the partition function of the ferromagnetic Ising model in the Lee-Yang circle of zeros given by |λ| = 1, where λ is the external field of the model. Complex-valued parameters for the Ising model are relevant for quantum circuit computations and phase transitions in statistical physics, but have also been key in the recent deterministic approximation scheme for all |λ| ≠ 1 by Liu, Sinclair, and Srivastava. Here, we focus on the unresolved complexity picture on the unit circle, and on the tantalising question of what happens in the circular arc around λ = 1, where on one hand the classical algorithm of Jerrum and Sinclair gives a randomised approximation scheme on the real axis suggesting tractability, and on the other hand the presence of Lee-Yang zeros alludes to computational hardness. Our main result establishes a sharp computational transition at the point λ = 1; in fact, our techniques apply more generally to the whole unit circle |λ| = 1. We show #P-hardness for approximating the partition function on graphs of maximum degree Δ when b, the edge-interaction parameter, is in the interval [EQUATION] and λ is a non-real on the unit circle. This result contrasts with known approximation algorithms when |λ| ≠ 1 or [EQUATION], and shows that the Lee-Yang circle of zeros is computationally intractable, even on bounded-degree graphs. Our inapproximability result is based on constructing rooted tree gadgets via a detailed understanding of the underlying dynamical systems, which are further parameterised by the degree of the root. The ferromagnetic Ising model has radically different behaviour than previously considered anti-ferromagnetic models, and showing our #P-hardness results in the whole Lee-Yang circle requires a new high-level strategy to construct the gadgets. To this end, we devise an elaborate inductive procedure to construct the required gadgets by taking into account the dependence between the degree of the root of the tree and the magnitude of the derivative at the fixpoint of the corresponding dynamical system
Translation and Validation of the Greek Version of the Antipsychotics and Sexual Functioning Questionnaire (ASFQ)
Introduction
Sexual dysfunction in patients with psychoses may be associated with the psychiatric illness itself (negative symptoms, such as apathy, and avolition), comorbid somatic health, psychosocial factors (stigmatization, discrimination), and the use of psychotropic drugs. In Greece, research into the study of antipsychotic-induced sexual dysfunction is not sufficient.
Aim
This study was conducted to translate and validate the Greek version of the Antipsychotics and Sexual Functioning Questionnaire (ASFQ) in a sample of patients receiving antipsychotic treatment.
Methods
A “forward-backward translation” method was applied. A pilot study was conducted with 15 outpatients with schizophrenia and bipolar disorder under antipsychotics treatment. Patients also completed the “Subjects’ Response to Antipsychotics (SRA)” questionnaire in order to assess the validity of the ASFQ. The ASFQ and the SRA questionnaire were completed twice within 2 weeks.
Main outcome measures
Reliability (internal consistency and test-retest) and validity were assessed.
Results
The Greek translation of ASFQ was reliable, with excellent internal consistency (Cronbach's a = 0.90 for men and 0.95 for women in both measurements). In addition, the Spearman correlation coefficient was 1 (P< .001) in all Likert-type questions in both assessments. Finally, Spearman correlation coefficients between ASFQ and SRA were moderately positive to strongly positive (between 0.25 and 1) in both assessments, demonstrating moderate to high validity.
Conclusions
The Greek version of the ASFQ has proved to be a reliable and valid clinical instrument, hence it can be used in further studies in the Greek population. Angelaki M, Galanis P, Igoumenou A, et al. Translation and Validation of the Greek Version of the Antipsychotics and Sexual Functioning Questionnaire (ASFQ). J Sex Med 2021;9:100334
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