No abstract

Relevance feedback techniques have demonstrated to be a powerful means to improve the results obtained when a user submits a query to an information retrieval system as the world wide web search engines. These kinds of techniques modify the user original query taking into account the relevance judgements provided by him on the retrieved documents, making it more similar to those he judged as relevant. This way, the new generated query permits to get new relevant documents thus improving the retrieval process by increasing recall. However, although powerful relevance feedback techniques have been developed for the vector space information retrieval model and some of them have been translated to the classical Boolean model, there is a lack of these tools in more advanced and powerful information retrieval models such as the fuzzy one. In this contribution we introduce a relevance feedback process for extended Boolean (fuzzy) information retrieval systems based on a hybrid evolutionary algorithm combining simulated annealing and genetic programming components. The performance of the proposed technique will be compared with the only previous existing approach to perform this task, Kraft et al.'s method, showing how our proposal outperforms the latter in terms of accuracy and sometimes also in time consumption. Moreover, it will be showed how the adaptation of the retrieval threshold by the relevance feedback mechanism allows the system effectiveness to be increased.

No abstract

Carmen Zarco es doctora en documentación científica y master en marketing y comportamiento del consumidor por la Universidad de Granada. Su vida profesional se ha desarrollado durante más de quince años en varias empresas como responsable de gestión del conocimiento. A lo largo de su carrera ha publicado una decena de artículos científicos, algunos de ellos en revistas JCR, y ha participado en varios proyectos y contratos de investigación. Es profesora asociada

No abstract

No abstract

No abstract

Communication is now a valuable element to demonstrate the degree of commitment and transparency that organizations have towards Sustainability. In a critical moment such that experienced with the COVID-19 crisis, companies recognized facing the challenge of continuous and committed communication on social networks as a sustainable activity. All the latter raises the question whether the brands recognized as the most sustainable have actually succeed on being aware of communicating at the most critical moments of the COVID-19 crisis. In this context, an analysis is made of the activity maintained by the main sustainable companies, both Spanish and Italian, within two of the most popular social networks, Twitter and Instagram, at the very early stages of the crisis in both countries. Our results show that most companies have managed to rise to the occasion and show their commitment to the population through social networks.