1,721,028 research outputs found
Burnout, learning and self-esteem at school: an empirical study
No full textIt is assumed that the level of school performance increases if the student has a good idea of self-esteem as well as his abilities, capabilities and skills in general. This paper investigates the relationship between level of self-esteem and school performance. The study, related to a survey conducted on a group of students aged from eight to thirteen, also aims to understand if the level of burnout of teachers influences the self-esteem and school performance of students. The causal relationships among the variables are investigated through a structural equation model (SEM)
Parametric functional analysis of variance for fish biodiversity assessment
No full textDue to the increasing impact of human activities, water conservation has become a primary aim of
environmental management policies. In this context, fish biodiversity represents a good measure of
water quality because changes in ecological factors involve qualitative modifications in species
composition. For this reason, the analysis of the interaction between biodiversity and environmental
characteristics becomes crucial. This paper aims to analyse the effects of habitat and seasonality on fish
biodiversity in freshwater environments. In particular, we applied functional data analysis to the beta
diversity profile. The proposed approach allows us to overcome the limitations of the classical
biodiversity indices, highlighting its multidimensional aspect. More in detail, our research focuses on
the functional data analysis of variance in order to quantify the effects exerted on a functional
observation by some factors. This model is applied to a real data set concerning ichthyic biodiversity of
104 streams in the province of Arezzo (Central Italy). We consider first the fish zonation and then the
seasonality as factors; the results show that species diversity fluctuates seasonally whereas the zonation
has no significant effect in influencing the biodiversity. Our proposal is a powerful tool for the analysis
of the relationship between qualitative variables and a functional response. Since the diversity profile is
a function of the relative abundance vector in a fixed domain, this method is particularly suited to the
beta profile and it could be very helpful to monitor or to identify areas of high environmental ris
Parametric functional analysis of variance for fish biodiversity
No full textConservation and restoration of biodiversity in marine environment is a crucial aspect of fishing and related activities. Human activities cause changes in fish population and deep transformation in the type and quality of the water. Fishing, restocking and pollution often bring to reduction and distribution changes of indigenous fish species to the benefit of the diffusion of exotic species. In this context protection and management of water environments become a primary objective. Therefore it is necessary to implement initiatives for protecting and restoring the quality and integrity of native species. Any decision-making process must be based on a careful analysis of the collected data. In this paper we propose a parametric functional approach to study the biodiversity in marine environment
BioFTF: An R Package for Biodiversity Assessment with the Functional Data Analysis Approach
No full textThis paper presents the R package BioFTF, which is a tool for statistical biodiversity assessment in the functional data analysis
framework. Diversity is a key topic in many research fields; however, in the literature, it is demonstrated that the existing indices do
not capture the different aspects of this concept. Thus, a main drawback is that different indicators may lead to different orderings
among communities according to their biodiversity. A possible method to evaluate biodiversity consists in using diversity profiles
that are curves depending on a specific parameter. In this setting, it is possible to adopt some functional instruments proposed in
the literature, such as the first and second derivatives, the curvature, the radius of curvature and the arc length. Specifically, the
derivatives and the curvature (or the radius of curvature) highlight any peculiar behaviour of the profiles, whereas the arc length
helps in ranking curves, given the richness. Because these instruments do not solve the issue of ranking communities with different
numbers of species, we propose an important methodological contribution that introduces the surface area. Indeed, this tools is a
scalar measure that reflects the information provided by the biodiversity profile and allows for ordering communities with different
richness. However, this approach requires mathematical skills that the average user may not have; thus, our idea is to provide a
user-friendly tool for both non-statistician and statistician practitioners to measure biodiversity in a functional context
Environmental monitoring through functional biodiversity tools
No full textThe foundational concept for our research, which is largely shared by statisticians and ecologists, is thatbiodiversity is one of the most important indicators for environmental assessment. Because this indicatordecreases in relation to ecosystem stressors, its measurement is essential for predicting future biologicalimpacts of environmental damages. Although many indices have been proposed, no universally acceptedmeasure for biodiversity has yet been established. In this context, the use of diversity profiles allows theanalyst to display a family of indices in a single graph. However, this approach presents two critical lim-itations: first, a community composition is not always interpretable; second, the diversity profiles couldlead to ranking issues when the curves intersect each other. The aim of this paper is to resolve theselimitations by introducing functional biodiversity tools. In particular, three functional measures are pro-posed: the derivatives, the radius of curvature and the curve length. The analysis of derivatives and ofthe radius of curvature addresses the first limitation and highlights the characteristics, the differencesand the similarities among communities. Arc length addresses the second limitation, providing a scalarmeasure that leads to a unique communities ranking for a given pattern of richness even if profiles inter-sect. The proposed functional models are applied to a real data set involving lichen biodiversity in theprovince of Genoa, Italy. Our approach allowed us to analyze the characteristics of lichen communities andto identify the biodiversity ranking. The combined use of these tools provides a useful method for iden-tifying areas of high environmental risk, with the potential to address the monitoring of environmentalpolicies
Burnout, learning and self-esteem at school: an empirical study
Full text linkIt is assumed that the level of school performance increases if the student has a good idea of self-esteem as well as his abilities, capabilities and skills in general. This paper investigates the relationship between level of self-esteem and school performance. The study, related to a survey conducted on a group of students aged from eight to thirteen, also aims to understand if the level of burnout of teachers influences the self-esteem and school performance of students. The causal relationships among the variables are investigated through a structural equation model (SEM)
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