Simona Balbi

A multidisciplinary approach for the characterization of the coastal marine ecosystems of Monte Di Procida (Campania, Italy)

A multidisciplinary survey was carried out on the quality of water and sediments of a coastal protected marine area, embedded between the inputs from Bagnoli steel plant to the south and a sewage plant, Volturno River and Regi Lagni channel to the north. The study integrated chemical-sedimentological data with biological and ecotoxicological analyses to assess anthropogenic pressures and natural variability. Data reveal marked differences in anthropogenic pollution between southeastern and northwestern zone, with the north affected by both inorganic and organic flows and the south influenced by levels of As, Pb and Zn in the sediments above law limits, deriving from inputs of the Bagnoli brownfield site. Meiobenthic data revealed at south higher relative abundance of sensitive species to pollution and environmental stress to the south, i.e. Lobatula lobatula and Rosalina bradyi, whereas to the north relative abundance of stress tolerant Quinqueloculina lata, Quinqueloculina pygmaea and Cribroelphidium cuvilleri were determined.

Contributions of Textual Data Analysis to Text Retrieval

The aim of this paper is to show how Textual Data Analysis techniques, developed in Europe under the influence of the Analyse Multidimen-sionelle des Donnees School, can improve performance of the LSI retrieval method. A first improvement can be obtained by properly considering the data contained in a lexical table. LSI is based on Euclidean distance, which is not adequate for frequency data. By using the chi-squared metric, on which Correspondence Analysis is based, significant improvements can be achieved. Further improvements can be obtained by considering external information such as keywords, authors, etc. Here an approach to text retrieval with external information based on PLS regression is shown. The suggested strategies are applied in text retrieval experiments on medical journal abstracts.

Procrustes Techniques for Text Mining

This paper aims at exploring the capability of the so called Latent Semantic Analysis applied to a multilingual context. In particular we are interested in weighing how it could be useful in solving linguistic problems, moving from a statistical point of view. Here we focus on the possibility of evaluating the goodness of a translation by comparing the latent structures of the original text and its version in another natural language. Procrustes rotations are introduced in a statistical framework as a tool for reaching this goal. An application on one year of Le Monde Diplomatique and the corresponding Italian edition will show the effectiveness of our proposal.

Statistical Tools in the Joint Analysis of Closed and Open-Ended Questions

The paper aims at presenting some statistical exploratory methods useful in the joint analysis of data collected in a survey, by means of closed and open-ended questions. After a quick review of the main steps necessary for transforming texts in a numerical table, we focus our attention on Lexical Correspondence Analysis. This method is a popular technique for analysing a lexical table obtained by cross-classifying respondents and free responses. As our interest is often in measuring and visualising the association between socio-demographic characteristics and lexical behaviour, the modalities of one or more closed-ended questions are used both for aggregating individuals similar with respect to the considered variables and reducing the sparseness of the lexical table. Dealing with textual data, the effectiveness of a non symmetrical variant of correspondence analysis is introduced. Furthermore, the advantages of asking a free description of the desired product in a conjoint analysis questionnaire is shown, by applying a factorial conjoint analysis with the lexical table as external information.

A Doubly Projected Analysis for Lexical Tables

This chapter aims to show how external information contributes in analysing a lexical table by enriching the readability of factorial maps. The theoretical frame is given by principal component analysis onto a reference subspace, a method based on the orthogonal projection of a correlation structure on the space spanned by an external set of explanatory variables. In previous papers the idea of a projected lexical analysis has been introduced by using a single reference space for terms. Here we consider a double projection strategy by involving external informative structures both on documents and terms, i.e., on rows and columns of a lexical table.

Profiling and Labour Market Accessibility for the Graduates in Economics at Naples University

In this paper, after defining a pseudo-panel of groups observed at subsequent times, we propose a strategy for the construction of a set of association rules related to different survey occasions. First, we measure the similarity between systems built at different times for understanding the stability of the phenomenon. We apply a procedure developed for symbolic data analysis for this purpose. The procedure consists of two phases: the definition of the pseudo-panel and that of a system of rules referred to the semantic marking technique. Then, the agreement between the systems is measured. We applied such a strategy for studying the labour market accessibility for graduate in Economics, the University of Naples “Federico II”, and the market evolution during an eight-year time span.

Visualization Techniques for Non Symmetrical Relations

Many strategies of Text Retrieval are based on Latent Semantic In- dexing and its variations, by considering different weighting systems for words and documents. Correspondence Analysis and L.S.I. share the basic algebraic tool, i.e. the Singular Value Decomposition and its generalisation, related to the use of a different way for measuring the importance of each element, both in determining and representing similarities between documents and words. Aim of the paper is to propose a peculiar factorial approach for better visualizing the relations between textual data and documents, compared with classical Correspondence Analysis. Here we consider a term frequency/document frequency index scheme, mainly developed for Text Retrieval, in a textual data analysis context. An application on Italian Le Monde Diplomatique corpus (about 2000 articles published from 1998 to 2003 in the Italian edition of LMD) will show the effectiveness of the proposal.

Combining different evaluation systems on social media for measuring user satisfaction

Abstract Web 2.0 allows people to express and share their opinions about products and services they buy/use. These opinions can be expressed in various ways: numbers, texts, emoticons, pictures, videos, audios, and so on. There has been great interest in the strategies for extracting, organising and analysing this kind of information. In a social media mining framework, in particular, the use of textual data has been explored in depth and still represents a challenge. On a rating and review website, user satisfaction can be detected both from a rating scale and from the written text. However, in common practice, there is a lack of algorithms able to combine judgments provided with both comments and scores. In this paper we propose a strategy to jointly measure the user evaluations obtained from the two systems. Text polarity is detected with a sentiment-based approach, and then combined with the associated rating score. The new rating scale has a finer granularity. Moreover, also enables the reviews to be ranked. We show the effectiveness of our proposal by analysing a set of reviews about the Uffizi Gallery in Florence (Italy) published on TripAdvisor.

BMS: An improved Dunn index for Document Clustering validation

Abstract Document Clustering aims at organizing a large quantity of unlabeled documents into a smaller number of meaningful and coherent clusters. One of the main unsolved problems in the literature is the lack of a reliable methodology to evaluate the results, although a wide variety of validation measures has been proposed. Validation measures are often unsatisfactory with numerical data, and even underperforming with textual data. Our attention focuses on the use of cosine similarity into the clustering process. A new measure based on the same criterion is here proposed. The effectiveness of the proposal is shown by an extensive comparative study.

Competences and Professional Options of the Italian Graduates: Results from the Textual Analysis of the Degree Course Information Data

The present chapter, developed within a research project promoted by the National Committee for the Evaluation of the University System (CNVSU, the complete report is available on www.cnvsu.it), analyses the Italian university offer, focusing on the communication adopted by the Universities to publicise their objectives and the results expected, also with respect to the potential employments. The analysed documents are the course information sheets of all the 3-year degree courses and some specialised (2-year) degree courses, contained in the OFF.F database of the Ministry of the University (MIUR) for the academic year 2005/2006. The research pursued the following aims: