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Unfairness towards subjective opinions in Machine Learning [article]

Agathe Balayn, Alessandro Bozzon, Zoltan Szlavik
2019 arXiv   pre-print
Despite the high interest for Machine Learning (ML) in academia and industry, many issues related to the application of ML to real-life problems are yet to be addressed. Here we put forward one limitation which arises from a lack of adaptation of ML models and datasets to specific applications. We formalise a new notion of unfairness as exclusion of opinions. We propose ways to quantify this unfairness, and aid understanding its causes through visualisation. These insights into the functioning
more » ... f ML-based systems hint at methods to mitigate unfairness.
arXiv:1911.02455v1 fatcat:5fjqhfk5orexrhsoxzqlxhn6la

Metadata Representations for Queryable ML Model Zoos [article]

Ziyu Li, Rihan Hai, Alessandro Bozzon, Asterios Katsifodimos
2022 arXiv   pre-print
Machine learning (ML) practitioners and organizations are building model zoos of pre-trained models, containing metadata describing properties of the ML models and datasets that are useful for reporting, auditing, reproducibility, and interpretability purposes. The metatada is currently not standardised; its expressivity is limited; and there is no interoperable way to store and query it. Consequently, model search, reuse, comparison, and composition are hindered. In this paper, we advocate for
more » ... standardized ML model meta-data representation and management, proposing a toolkit supported to help practitioners manage and query that metadata.
arXiv:2207.09315v1 fatcat:okbik52a2na57oiia7wfpta7ki

Modeling Search Computing Applications [chapter]

Alessandro Bozzon, Marco Brambilla, Alessandro Campi, Stefano Ceri, Francesco Corcoglioniti, Piero Fraternali, Salvatore Vadacca
2010 Lecture Notes in Computer Science  
Search Computing defines a new class of applications, which enable end users to perform exploratory search processes over multi-domain data sources available on the Web. These applications exploit suitable models, supported by a framework, that make it possible for expert users to configure the data sources to be searched and the interfaces for query submission and result visualization, by using for such source and interface configurations mash-up tools which do not require programming. This
more » ... er presents Search Computing design process and developer roles, together with the conceptual models that represent the foundation of a model-driven approach to Search Computing.
doi:10.1007/978-3-642-16985-4_6 fatcat:bwrd643ubvbcxpnfdkzqhhqcsy

Inferring Student Attention with ASQ [chapter]

Vasileios Triglianos, Cesare Pautasso, Alessandro Bozzon, Claudia Hauff
2016 Lecture Notes in Computer Science  
ASQ is a Web application for broadcasting and tracking interactive presentations, which can be used to support active learning pedagogies during lectures, labs and exercise sessions. Students connect their smartphones, tablets or laptops to receive the current slide as it is being explained by the teacher. Slides can include interactive teaching elements (usually questions of different forms). In contrast to other existing platforms, ASQ does not only collect, aggregate and visualize the
more » ... in real-time, it also supports the data analytics in the classroom paradigm by providing the teacher with a real-time analysis of student behaviour during the entire session. One vital aspect of student behaviour is (in)attention and in this paper we discuss how we infer -in real-time -student attention based on log traces ASQ collects.
doi:10.1007/978-3-319-45153-4_23 fatcat:y5qe2qjhl5gfxpdelkczu6a7di

Towards an Ontological Representation of Services in Search Computing [chapter]

Fabian Suchanek, Alessandro Bozzon, Emanuele Della Valle, Alessandro Campi, Stefania Ronchi
2011 Lecture Notes in Computer Science  
In the Search Computing project, Web services are modeled by the Semantic Resource Framework (SRF). In this article, we argue that the SRF could benefit from ontological concepts borrowed from the Semantic Web. We first present the knowledge representation used in the Semantic Web, notably in the YAGO ontology [14] . We show how this model is used in the ANGIE system [12] to represent Web Services in conjunction with YAGO. We draw parallels to the Service Mart [3] model used in SeCo. We propose
more » ... a symbiosis of the two models, discussing the challenges and advantages that come with the integrated model.
doi:10.1007/978-3-642-19668-3_9 fatcat:owosix2blfbgrp4anfkyi22tpy

A Model-Driven Approach for Crowdsourcing Search

Alessandro Bozzon, Marco Brambilla, Andrea Mauri
2012 The Web Conference  
Even though search systems are very efficient in retrieving world-wide information, they can not capture some peculiar aspects and features of user needs, such as subjective opinions and recommendations, or information that require local or domain specific expertise. In this kind of scenario, the human opinion provided by an expert or knowledgeable user can be more useful than any factual information retrieved by a search engine. In this paper we propose a model-driven approach for the
more » ... tion of crowd-search tasks, i.e. activities where real people -in real time -take part to the generalized search process that involve search engines. In particular we define two models: the "Query Task Model", representing the metamodel of the query that is submitted to the crowd and the associated answers; and the "User Interaction Model", which shows how the user can interact with the query model to fulfill her needs. Our solution allows for a top-down design approach, from the crowd-search task design, down to the crowd answering system design. Our approach also grants automatic code generation thus leading to quick prototyping of search applications based on human responses collected over social networking or crowdsourcing platforms.
dblp:conf/www/BozzonBM12 fatcat:tgbxxfhhxrgjrl4s6k2dnmpvju

Searching Repositories of Web Application Models [chapter]

Alessandro Bozzon, Marco Brambilla, Piero Fraternali
2010 Lecture Notes in Computer Science  
Project repositories are a central asset in software development, as they preserve the technical knowledge gathered in past development activities. However, locating relevant information in a vast project repository is problematic, because it requires manually tagging projects with accurate metadata, an activity which is time consuming and prone to errors and omissions. This paper investigates the use of classical Information Retrieval techniques for easing the discovery of useful information
more » ... om past projects. Differently from approaches based on textual search over the source code of applications or on querying structured metadata, we propose to index and search the models of applications, which are available in companies applying Model-Driven Engineering practices. We contrast alternative index structures and result presentations, and evaluate a prototype implementation on real-world experimental data.
doi:10.1007/978-3-642-13911-6_1 fatcat:za6y2qnsnzh4ve74c244o57x6u

Reactive crowdsourcing

Alessandro Bozzon, Marco Brambilla, Stefano Ceri, Andrea Mauri
2013 Proceedings of the 22nd international conference on World Wide Web - WWW '13  
An essential aspect for building effective crowdsourcing computations is the ability of "controlling the crowd", i.e. of dynamically adapting the behaviour of the crowdsourcing systems as response to the quantity and quality of completed tasks or to the availability and reliability of performers. Most crowdsourcing systems only provide limited and predefined controls; in contrast, we present an approach to crowdsourcing which provides fine-level, powerful and flexible controls. We model each
more » ... wdsourcing application as composition of elementary task types and we progressively transform these high level specifications into the features of a reactive execution environment that supports task planning, assignment and completion as well as performer monitoring and exclusion. Controls are specified as active rules on top of data structures which are derived from the model of the application; rules can be added, dropped or modified, thus guaranteeing maximal flexibility with limited effort. We also report on our prototype platform that implements the proposed framework and we show the results of our experimentations with different rule sets, demonstrating how simple changes to the rules can substantially affect time, effort and quality involved in crowdsourcing activities.
doi:10.1145/2488388.2488403 dblp:conf/www/BozzonBCM13 fatcat:xzvtm7xgn5gd7n5xmvbxisehrm

Liquid query

Alessandro Bozzon, Marco Brambilla, Stefano Ceri, Piero Fraternali
2010 Proceedings of the 19th international conference on World wide web - WWW '10  
In this paper we propose the Liquid Query paradigm, to support users in finding responses to multi-domain queries through exploratory information seeking across structured information sources (Web documents, deep Web data, and personal data repositories), wrapped by means of a uniform notion of search service. Liquid Query aims at filling the gap between generalpurpose search engines, which are unable to find information spanning multiple topics, and domain-specific search systems, which cannot
more » ... go beyond their domain limits. The Liquid Query interface consists of interaction primitives that let users pose questions and explore results spanning over multiple sources incrementally, thus getting closer and closer to the sought information. We demonstrate our approach with a prototype built upon the YQL (Yahoo! Query Language) framework.
doi:10.1145/1772690.1772708 dblp:conf/www/BozzonBCF10 fatcat:23m5obav4fhwfewbslyca5r7qu

Diversification for Multi-domain Result Sets [chapter]

Alessandro Bozzon, Marco Brambilla, Piero Fraternali, Marco Tagliasacchi
2012 Lecture Notes in Computer Science  
Multi-domain search answers to queries spanning multiple entities, like "Find an affordable house in a city with low criminality index, good schools and medical services", by producing ranked sets of entity combinations that maximize relevance, measured by a function expressing the user's preferences. Due to the combinatorial nature of results, good entity instances (e.g., inexpensive houses) tend to appear repeatedly in top-ranked combinations. To improve the quality of the result set, it is
more » ... portant to balance relevance (i.e., high values of the ranking function) with diversity, which promotes different, yet almost equally relevant, entities in the top-k combinations. This paper explores two different notions of diversity for multi-domain result sets, compares experimentally alternative algorithms for the trade-off between relevance and diversity, and performs a user study for evaluating the utility of diversification in multi-domain queries.
doi:10.1007/978-3-642-31753-8_10 fatcat:csabsrc4ejdynmp3leyxjr4eui

Social Smart Meter

Andrea Mauri, Achilleas Psyllidis, Alessandro Bozzon
2018 Companion of the The Web Conference 2018 on The Web Conference 2018 - WWW '18  
Having a thorough understanding of energy consumption behavior is an important element of sustainability studies. Traditional sources of information about energy consumption, such as smart meter devices and surveys, can be costly to deploy, may lack contextual information or have infrequent updates. In this paper, we examine the possibility of extracting energy consumption-related information from user-generated content. More specifically, we develop a pipeline that helps identify
more » ... content in Twitter posts and classify it into four categories (dwelling, food, leisure, and mobility), according to the type of activity performed. We further demonstrate a web-based application -called Social Smart Meter -that implements the proposed pipeline and enables different stakeholders to gain an insight into daily energy consumption behavior, as well as showcase it in case studies involving several world cities.
doi:10.1145/3184558.3186977 dblp:conf/www/0001PB18 fatcat:fdrvskotdraobin7mhuckkpdam

Efficient Execution of Top-K SPARQL Queries [chapter]

Sara Magliacane, Alessandro Bozzon, Emanuele Della Valle
2012 Lecture Notes in Computer Science  
Top-k queries, i.e. queries returning the top k results ordered by a user-defined scoring function, are an important category of queries. Order is an important property of data that can be exploited to speed up query processing. State-of-the-art SPARQL engines underuse order, and top-k queries are mostly managed with a materialize-then-sort processing scheme that computes all the matching solutions (e.g. thousands) even if only a limited number k (e.g. ten) are requested. The SPARQL-RANK
more » ... is an extended SPARQL algebra that treats order as a first class citizen, enabling efficient split-and-interleave processing schemes that can be adopted to improve the performance of top-k SPARQL queries. In this paper we propose an incremental execution model for SPARQL-RANK queries, we compare the performance of alternative physical operators, and we propose a rank-aware join algorithm optimized for native RDF stores. Experiments conducted with an open source implementation of a SPARQL-RANK query engine based on ARQ show that the evaluation of top-k queries can be sped up by orders of magnitude. 1 SELECT ?product ?of fer (g1(?avgRat1) + g2(?avgRat2) + g3(?price1) AS ?score) 2 WHERE { ?product hasAvgRating1 ?avgRat1 . 3 ?product hasAvgRating2 ?avgRat2 . 4 ?product hasName ?name . 5 ?product hasOffers ?of fer . 6 ?of fer hasPrice ?price1 } 7 ORDER BY DESC(?score) LIMIT 10 Listing 1.1. A top-k SPARQL query that retrieves the best ten offers of products ordered by a function of user ratings and offer price; gi are normalization functions and the bold letters represent the abbreviations used in the following examples P. Cudré-Mauroux et al. (Eds.): ISWC 2012, Part I, LNCS 7649, pp. 344-360, 2012.
doi:10.1007/978-3-642-35176-1_22 fatcat:wtfyzolrvbhopnrvhm3dxfio3i

On Development Practices for End Users [chapter]

Alessandro Bozzon, Marco Brambilla, Muhammad Imran, Florian Daniel, Fabio Casati
2011 Lecture Notes in Computer Science  
The paper discusses some trends in end user programming (EUP) and takes inspiration from the discussions in a panel and in a vertical session on research evaluation within the second Search Computing workshop. We discuss the controversial successes and failures in this field and we elaborate on which facilities could foster adoption of end user programming. We discuss various dimensions of end user programming, including vertical versus horizontal language definition, declarative versus
more » ... ve approaches. We exemplify our discussion in the realistic scenario of research evaluation by comparing the Search Computing and ResEval approaches.
doi:10.1007/978-3-642-19668-3_18 fatcat:2wii24cjrffv7b4v45i5lwj2vu

CitRec 2017

Jie Yang, Zhu Sun, Alessandro Bozzon, Jie Zhang, Martha Larson
2017 Proceedings of the Eleventh ACM Conference on Recommender Systems - RecSys '17  
Bozzon, Jie Zhang, and Martha Larson recommendation based techniques to enhance citizens' living experiences.  ...  Thus they describe comprehensively citizens' behaviors and their relationships with the environment, providing opportunities for RecSys '17, August 27-31, 2017, Como, Italy Jie Yang, Zhu Sun, Alessandro  ... 
doi:10.1145/3109859.3109969 dblp:conf/recsys/YangSBZL17 fatcat:w7glpy4gmjfmvn6eccvl53i4ni

Designing Evaluations of Machine Learning Models for Subjective Inference: The Case of Sentence Toxicity [article]

Agathe Balayn, Alessandro Bozzon
2019 arXiv   pre-print
Machine Learning (ML) is increasingly applied in real-life scenarios, raising concerns about bias in automatic decision making. We focus on bias as a notion of opinion exclusion, that stems from the direct application of traditional ML pipelines to infer subjective properties. We argue that such ML systems should be evaluated with subjectivity and bias in mind. Considering the lack of evaluation standards yet to create evaluation benchmarks, we propose an initial list of specifications to
more » ... prior to creating evaluation datasets, in order to later accurately evaluate the biases. With the example of a sentence toxicity inference system, we illustrate how the specifications support the analysis of biases related to subjectivity. We highlight difficulties in instantiating these specifications and list future work for the crowdsourcing community to help the creation of appropriate evaluation datasets.
arXiv:1911.02471v1 fatcat:cjac3tgjmjgoxnhswqcocjemcu
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