1,722,533 research outputs found
From Pipeline Optimization To Problem-oriented Automl: Advancing Clustering Automation
Full text linkAutomated Machine Learning (AutoML) aims to lower the entry barrier of machine
learning by automating the design of pipelines, including the selection of techniques,
algorithms and their parameters. While substantial progress has been made in supervised
learning, unsupervised learning remains challenging due to the absence of universal goals
such as accuracy. In this context, meta-learning plays a crucial role by leveraging prior
knowledge to recommend algorithms or configurations based on dataset characteristics.
Yet clustering is inherently subjective: success often depends on user goals. Since Au-
toML’s mission is to place the user at the center, this thesis explores how AutoML and
meta-learning can be unified to automatically provide users with problem-oriented clus-
tering pipelines.
We first investigate pipeline synthesis by extending evolutionary optimisation meth-
ods from supervised learning to clustering. Benchmarking across diverse datasets shows
that optimising for individual clustering validity indices or their ensembles is insufficient.
These results motivate the use of meta-objectives and surrogate models to flexibly guide
search in alignment with user intent.
Next, we study what is required to build robust meta-spaces and meta-objectives.
Through a systematic review of AutoClustering literature, we propose a taxonomy of
datasets and meta-features, analyse their influence, and show how meta-models can be
simplified without substantial performance loss.
Finally, we integrate these insights into the Problem-oriented AutoML in Clustering
(PoAC) framework, which aligns meta-features, objectives, and optimisation strategies
with problem-specific requirements, enabling adaptive, algorithm-agnostic clustering au-
tomation.Automated Machine Learning (AutoML) aims to lower the entry barrier of machine
learning by automating the design of pipelines, including the selection of techniques,
algorithms and their parameters. While substantial progress has been made in supervised
learning, unsupervised learning remains challenging due to the absence of universal goals
such as accuracy. In this context, meta-learning plays a crucial role by leveraging prior
knowledge to recommend algorithms or configurations based on dataset characteristics.
Yet clustering is inherently subjective: success often depends on user goals. Since Au-
toML’s mission is to place the user at the center, this thesis explores how AutoML and
meta-learning can be unified to automatically provide users with problem-oriented clus-
tering pipelines.
We first investigate pipeline synthesis by extending evolutionary optimisation meth-
ods from supervised learning to clustering. Benchmarking across diverse datasets shows
that optimising for individual clustering validity indices or their ensembles is insufficient.
These results motivate the use of meta-objectives and surrogate models to flexibly guide
search in alignment with user intent.
Next, we study what is required to build robust meta-spaces and meta-objectives.
Through a systematic review of AutoClustering literature, we propose a taxonomy of
datasets and meta-features, analyse their influence, and show how meta-models can be
simplified without substantial performance loss.
Finally, we integrate these insights into the Problem-oriented AutoML in Clustering
(PoAC) framework, which aligns meta-features, objectives, and optimisation strategies
with problem-specific requirements, enabling adaptive, algorithm-agnostic clustering au-
tomation
Um estudo de pontos críticos degenerados e não degenerados
Full text linkSILVA, Matheus Maia. Um estudo de pontos críticos degenerados e não degenerados. 2024, 69f. Monografia - Curso de Matemática, Instituto De Ciências Exatas E
Da Natureza, Universidade da Integração Internacional da Lusofonia
Afro-Brasileira, Redenção-Ceará, 2024.Neste trabalho, realizamos um estudo aprofundado sobre a classificação dos pontos críticos,
com foco em sua distinção entre degenerados e não degenerados. Para os pontos críticos
não degenerados, empregamos o Lema de Morse, que permite uma classificação precisa
desses pontos a partir das características locais da função, quando a matriz Hessiana é diferente de zero. Já para os pontos críticos degenerados, aplicamos o “Splitting Lemma”,
uma ferramenta essencial que facilita a compreensão e o tratamento de pontos críticos
onde a matriz Hessiana se anula, apresentando uma estrutura mais complexa e deman-
dando uma análise diferenciada. Esse trabalho inclui um estudo detalhado dos germes de
funções, com foco específico nas funções de codimensão menor ou igual a cinco. Ao limitar
o estudo a esse intervalo, conseguimos uma análise rica e compreensiva das singularidades
de baixa a média complexidade, abordando tipos de singularidades que têm aplicações
em diversas áreas, como física e geometria
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Deficiências no atendimento público voltado a saúde da população lgbt e suas possíveis melhorias: uma revisão sistemática
Full text linkSILVA, Matheus Soares da. Deficiências no atendimento público voltado a saúde da
população lgbt e suas possíveis melhorias: uma revisão sistemática. 2020. 18f. TCC - Curso de Especialização em Gestão em Saúde, Instituto de Educação a Distância, Universidade da Integração Internacional da Lusofonia Afro-Brasileira,
Redenção-Ceará, 2020.Introdução: O direito à saúde no Brasil é resultado das lutas do Movimento da Reforma Sanitarista e está garantida na Constituição Federal de 1988. No texto a saúde não é entendida somente como promoção da assistência médico sanitária, mas de forma ampliada, o direito à saúde é decorrente do acesso das pessoas e coletividades aos bens e serviços públicos universais. Objetivos: Esta pesquisa teve como objetivo principal o intuito de Identificar, na literatura científica, as deficiências no atendimento público voltado a saúde LGBT, sendo possível através da identificação das
deficiências encontradas pelos membros da comunidade LGBT no atendimento oferecido pelo SUS e a possibilidade de defrontar-se com estratégias disponibilizadas nos materiais que podem vir a auxiliar no enfrentamento das mesmas. Metodologia: Este foi um estudo organizado através de uma revisão bibliográfica sistemática, utilizando-se das bases de dados Scielo, LILACS e BVS, tendo enquanto critérios de inclusão os seguintes: publicações de artigos científicos entre os anos de 2010 a 2019, que estivessem disponíveis na íntegra e na língua portuguesa. Principais
resultados: Conseguiu-se constatar que o atendimento da população LGBT no âmbito da saúde público ainda passa por dificuldades, incluindo preconceitos e discriminações de vários tipos, somando assim para uma maior evasão da busca pela saúde. Considerações finais: Acredita-se que a saúde LGBT tem ganhado espaço no SUS e na mídia, mais ainda há muito o que ser feito para que o atendimento e busca pela saúde não seja torturante e vexatória
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
- …
