arXiv subjects

Fátima Velásquez-Rojas

Publications and source records attributed to Fátima Velásquez-Rojas.

4 recordsLinked to original sources

arXiv2022

Effects of the COVID-19 pandemic in higher education: a particular case from the perspective of complex systems

The COVID-19 pandemic abruptly changed the classroom context, understood as the meeting space between teachers and students where a fundamental part of the construction of new knowledge takes place. This presented enormous challenges for all actors in the educational process, who had to overcome multiple difficulties and adapt to a new daily life in which the incorporation of new strategies and tools was essential. In this work we study the knowledge acquisition process in two different contexts: face-to-face (before the onset of the pandemic) and virtual (during confinement), for a particular case in higher education in Argentina. We developed an analytical model for the knowledge acquisition process, based on a series of surveys and information on academic performance. We analyzed the significance of the model by means of Artificial Neural Networks and a Multiple Linear Regression Method. We found that the virtual context produced a decrease in motivation to learn. We also found that the structure of the emerging contact network from peer interaction presents very different characteristics in both contexts. Finally, we show that in all cases, interaction with teachers is of utmost importance in the process of acquiring knowledge.

physics.soc-ph↗

arXiv2021

The knowledge acquisition process from a complex system perspective: observations and models

In this work we study the knowledge acquisition process in a teaching-learning scenario that takes place within the classroom. We explore two complementary approaches, which include classroom observations and student surveys, and the formulation of theoretical models through the use of Statistical Physics tools. We develop an analytical model and a set of dynamics agent-based models that allow us to understand global behaviors, as well as to follow individual trajectories in the knowledge acquisition process. As a proxy of the final achievements of the students we use their final grade, allowing us to assess the validity of our approach. Our models, supported by observations and surveys, reproduce fairly well the process of acquiring knowledge of the students. This work sheds light on the internal dynamics of the classroom and allows us to understand some global aspects of the teaching-learning process.

physics.ed-ph↗

arXiv2020

Disease and information spreading at different speeds in multiplex networks

Nowadays, one of the challenges we face when carrying out modeling of epidemic spreading is to develop methods to control disease transmission. In this article we study how the spreading of knowledge of a disease affects the propagation of that disease in a population of interacting individuals. For that, we analyze the interaction between two different processes on multiplex networks: the propagation of an epidemic using the susceptible-infected-susceptible dynamics and the dissemination of information about the disease --and its prevention methods-- using the unaware-aware-unaware dynamics, so that informed individuals are less likely to be infected. Unlike previous related models where disease and information spread at the same time scale, we introduce here a parameter that controls the relative speed between the propagation of the two processes. We study the behavior of this model using a mean-field approach that gives results in good agreement with Monte Carlo simulations on homogeneous complex networks. We find that increasing the rate of information dissemination reduces the disease prevalence, as one may expect. However, increasing the speed of the information process as compared to that of the epidemic process has the counter intuitive effect of increasing the disease prevalence. This result opens an interesting discussion about the effects of information spreading on disease propagation.

physics.soc-ph↗

arXiv2018

Opinion dynamics in two dimensions: domain coarsening leads to stable bi-polarization and anomalous scaling exponents

We study an opinion dynamics model that explores the competition between persuasion and compromise in a population of agents with nearest-neighbor interactions on a two-dimensional square lattice. Each agent can hold either a positive or a negative opinion orientation, and can have two levels of intensity --moderate and extremist. When two interacting agents have the same orientation become extremists with persuasion probability $p$, while if they have opposite orientations become moderate with compromise probability $q$. These updating rules lead to the formation of same-opinion domains with a coarsening dynamics that depends on the ratio $r=p/q$. The population initially evolves to a centralized state for small $r$, where domains are composed by moderate agents and coarsening is without surface tension, and to a bi-polarized state for large $r$, where domains are formed by extremist agents and coarsening is driven by curvature. Consensus in an extreme opinion is finally reached in a time that scales with the population size $N$ and $r$ as $τ\simeq r^{-1} \ln N$ for small $r$ and as $τ\sim r^2 N^{1.64}$ for large $r$. Bi-polarization could be quite stable when the system falls into a striped state where agents organize into single-opinion horizontal, vertical or diagonal bands. An analysis of the stripes dynamics towards consensus allows to obtain an approximate expression for $τ$ which shows that the exponent $1.64$ is a result of the diffusion of the stripe interfaces combined with their roughness properties.

physics.soc-ph↗