Exploring the Efficacy of Binary Surveys versus Likert Scales in Assessing Student Perspectives Using Bayesian Analysis

[Abstract] Likert-scale surveys are the undeniable protagonists of online evaluations. They ask the respondent to express their degree of agreement with a series of statements related to the development of a subject. In contrast, in social networks, dichotomous surveys are mostly used. They force respondents to polarize their opinions by selecting “like” or “dislike”. This study compares the efficacy of binary and Likert surveys in gathering student opinions on mechanical engineering program subjects. Using Bayesian analysis, it analyzes the similarity of responses obtained from both formats. For each question and scale, the ratio of “I like” among the total responses collected was calculated. The Bayesian factor method was used to compare the ratios obtained. The null hypothesis was equality between the ratios obtained by the different scales for the same question. This hypothesis was rejected in only 7 of the 49 questions evaluated—less than 15%. Finally, the students were surveyed on the preference for use of both scales. More than 80% stated a preference for the use of the dichotomous format. In view of the results obtained, we recommend more frequent use of the dichotomous scale to gather students’ opinions

Multi-criteria risk assessment: Case study of a large hydroelectric project

This is a PDF file of an unedited manuscript that has been accepted for publication[Abstarct]: Run-of-river hydroelectric plants along Amazon River tributaries have been shown to be an ecologically viable alternative to meet Brazilian energy demand. These plants are a solution to add capacity. However, due to geographic and socioeconomic characteristics of this region, there are risks that cannot be disregarded. This study reports the application of multi-criteria analysis to identify risk events for the Santo Antonio Hydroelectric Plant under construction, related to service packs relevant to the project. The choice of the appropriate technique took into consideration the imprecision of subjective judgment. The fuzzy analytic hierarchy process (FAHP) enabled inserting a measure of inaccuracy, represented by the degree of fuzziness, assigned to each pairwise comparison. Fuzziness was incorporated into the process by means of a triangular membership function. The convergence of opinion was assessed by comparing the hierarchical order of the perceived risks identified by two distinct groups, the owner consortium, and the builder consortium. These groups have similar risk perceptions, despite having different roles and asymmetric risk sharing caused mainly by the characteristics and provisions contained in the engineering, procurement and construction (EPC) contract. The model was efficient in ranking the risk events from the perspective of the two groups, therefore constituting a rational and transparent approach for risk management in large projects

Search for composite and exotic fermions at LEP 2

A search for unstable heavy fermions with the DELPHI detector at LEP is reported. Sequential and non-canonical leptons, as well as excited leptons and quarks, are considered. The data analysed correspond to an integrated luminosity of about 48 pb^{-1} at an e^+e^- centre-of-mass energy of 183 GeV and about 20 pb^{-1} equally shared between the centre-of-mass energies of 172 GeV and 161 GeV. The search for pair-produced new leptons establishes 95% confidence level mass limits in the region between 70 GeV/c^2 and 90 GeV/c^2, depending on the channel. The search for singly produced excited leptons and quarks establishes upper limits on the ratio of the coupling of the excited fermio

Search for charginos in e+e- interactions at sqrt(s) = 189 GeV

An update of the searches for charginos and gravitinos is presented, based on a data sample corresponding to the 158 pb^{-1} recorded by the DELPHI detector in 1998, at a centre-of-mass energy of 189 GeV. No evidence for a signal was found. The lower mass limits are 4-5 GeV/c^2 higher than those obtained at a centre-of-mass energy of 183 GeV. The (\mu,M_2) MSSM domain excluded by combining the chargino searches with neutralino searches at the Z resonance implies a limit on the mass of the lightest neutralino which, for a heavy sneutrino, is constrained to be above 31.0 GeV/c^2 for tan(beta) \geq 1.Comment: 22 pages, 8 figure

Search for lightest neutralino and stau pair production in light gravitino scenarios with stau NLSP

Promptly decaying lightest neutralinos and long-lived staus are searched for in the context of light gravitino scenarios. It is assumed that the stau is the next to lightest supersymmetric particle (NLSP) and that the lightest neutralino is the next to NLSP (NNLSP). Data collected with the Delphi detector at centre-of-mass energies from 161 to 183 \GeV are analysed. No evidence of the production of these particles is found. Hence, lower mass limits for both kinds of particles are set at 95% C.L.. The mass of gaugino-like neutralinos is found to be greater than 71.5 GeV/c^2. In the search for long-lived stau, masses less than 70.0 to 77.5 \GeVcc are excluded for gravitino masses from 10 to 150 \eVcc . Combining this search with the searches for stable heavy leptons and Minimal Supersymmetric Standard Model staus a lower limit of 68.5 \GeVcc may be set for the stau mas

Design Thinking: experiencia en graos STEAM

[Resumo] Crear experiencias de aprendizaxe a través de proxectos na aula nas que os alumnos aprendan en equipo a resolver problemas complexos e desenvolvan o pensamento creativo e crítico, resulta un desafío. Design Thinking é unha metodoloxía cuxa meta é crear un deseño innovador baseado nas necesidades do usuario (User Experience). Empregando esta ferramenta, desenvolveuse na materia de Expresión Gráfica unha experiencia de deseño, modelado e impresión 3D ligada ao contexto actual de pandemia producida polo COVID-19. Nesta experiencia participaron estudantes de primeiro curso de tres graos do ámbito STEAM da Universidade de A Coruña. As actividades expuxéronse de tal maneira que se puidesen facer de forma presencial ou a distancia. A titorización e seguimento do progreso dos alumnos fíxose a través de Microsoft Teams e Moodle. Empregouse a ferramenta Taller de Moodle para a avaliación dos prototipos desenvolvidos. Os resultados da enquisa foron moi positivos. Os proxectos Design Thinking tamén tiveron un efecto positivo nas cualificacións.[Abstract] Creating learning experiences through classroom projects in which students learn as a team to solve complex problems and develop creative and critical thinking is a challenge. Design Thinking is a methodology whose goal is to create an innovative design based on the user's needs (User Experience). Using this tool, an experience of design, modeling and 3D printing linked to the current context of the pandemic produced by COVID-19 was developed in the subject of Graphic Expression. This experience involved first year students of three STEAM degrees of the University of A Coruña. The activities were planned in such a way that they could be done in person or remotely. Tutoring and monitoring of student progress was done through Microsoft Teams and Moodle. The Moodle Workshop tool was used for the evaluation of the developed prototypes. The survey results were very positive. Design Thinking projects also had a positive effect on the grades.http://hdl.handle.net/2183/2879