Communicative Language Teaching (CLT) in EFL Context: Exploring Afghan EFL Lecturers’ Perceived Challenges in Implementing CLT

Many studies have been conducted to investigate the implementation of Communicative Language Teaching (CLT) in ESL and EFL contexts, but those conducted in EFL context, have reported that the application of CLT was challenging. Still, as far as the Afghan EFL context is concerned, there is a lack of empirical research investigating the issue. Hence, the purpose of this study is to explore afghan EFL lecturers’ perceived challenges in practicing CLT. The study also aims to examine if there is any significant relationship among teachers use of CLT, the perceived challenges, and their demographic profiles. This study uses a quantitative research approach in which a survey questionnaire was given to EFL lecturers teaching in a public university. The results of the study revealed that the EFL lecturers had positive perceptions of using CLT activities, as there were evidence of a number of major CLT activities conducted in their classrooms. The results also revealed that they faced certain challenges that prevented them from implementing CLT effectively. Furthermore, significant correlation was found between students’ related challenges and teachers’ perceptions of using CLT; however, no significant correlations were found among teachers’ demographic profiles and CLT perceived challenges. This research is significant since it could be used as a resource presenting a comprehensive picture of CLT implementation in EFL classrooms in Afghanistan

Local Limit Theorem for the Lorentz Process and Its Recurrence in the Plane

For Young systems, i.e. for hyperbolic systems without/with singularities satisfying Lai-Sang Young's axioms (which imply exponential decay of correlation and the CLT) a local CLT is proven. In fact, a unified version of the local CLT is found, covering among others the absolutely contionuous and the arithmetic cases. For the planar Lorentz process with a finite horizon this result implies a.) the local CLT and b.) the recurrence. For the latter case ($d=2$, finite horizon), combining the global CLT with abstract ergodic theoretic ideas, K. Schmidt, and J.-P. Conze, could already establish recurrence

Adopting communicative language teaching (CLT) approach to enhance oral competencies among students: Teachers’ attitudes and beliefs

The idea of communicative competence is one of the most influential theoretical developments in language education as it helps redefine the objectives of second language (L2) instruction. Although most teachers acknowledge the importance of CLT, many do not genuinely practice it. This paper attempts to explore teachers’ reasons or reluctance in using CLT in the classroom. The role of CLT approach in enhancing oral competencies is examined by analyzing the attitudes and beliefs of the teachers. The data is gathered using interview sessions. A range of practical activities is proposed to help language teachers integrate CLT in their lessons

Central limit theorems for multilevel Monte Carlo methods

In this work, we show that uniform integrability is not a necessary condition for central limit theorems (CLT) to hold for normalized multilevel Monte Carlo (MLMC) estimators and we provide near optimal weaker conditions under which the CLT is achieved. In particular, if the variance decay rate dominates the computational cost rate (i.e., $\beta > \gamma$), we prove that the CLT applies to the standard (variance minimizing) MLMC estimator. For other settings where the CLT may not apply to the standard MLMC estimator, we propose an alternative estimator, called the mass-shifted MLMC estimator, to which the CLT always applies. This comes at a small efficiency loss: the computational cost of achieving mean square approximation error $\mathcal{O}(\epsilon^2)$ is at worst a factor $\mathcal{O}(\log(1/\epsilon))$ higher with the mass-shifted estimator than with the standard one

Central limit behavior of deterministic dynamical systems

We investigate the probability density of rescaled sums of iterates of deterministic dynamical systems, a problem relevant for many complex physical systems consisting of dependent random variables. A Central Limit Theorem (CLT) is only valid if the dynamical system under consideration is sufficiently mixing. For the fully developed logistic map and a cubic map we analytically calculate the leading-order corrections to the CLT if only a finite number of iterates is added and rescaled, and find excellent agreement with numerical experiments. At the critical point of period doubling accumulation, a CLT is not valid anymore due to strong temporal correlations between the iterates. Nevertheless, we provide numerical evidence that in this case the probability density converges to a $q$-Gaussian, thus leading to a power-law generalization of the CLT. The above behavior is universal and independent of the order of the maximum of the map considered, i.e. relevant for large classes of critical dynamical systems.Comment: 6 pages, 5 figure

Corrections to the Central Limit Theorem for Heavy-Tailed Probability Densities

Classical Edgeworth expansions provide asymptotic correction terms to the Central Limit Theorem (CLT) up to an order that depends on the number of moments available. In this paper, we provide subsequent correction terms beyond those given by a standard Edgeworth expansion in the general case of regularly varying distributions with diverging moments (beyond the second). The subsequent terms can be expressed in a simple closed form in terms of certain special functions (Dawson's integral and parabolic cylinder functions), and there are qualitative differences depending on whether the number of moments available is even, odd or not an integer, and whether the distributions are symmetric or not. If the increments have an even number of moments, then additional logarithmic corrections must also be incorporated in the expansion parameter. An interesting feature of our correction terms for the CLT is that they become dominant outside the central region and blend naturally with known large-deviation asymptotics when these are applied formally to the spatial scales of the CLT