0000000000478914
AUTHOR
Plaia Antonella
showing 6 related works from this author
L'esperienza della VQR 2011-2014 nell'area delle Scienze Economiche e Statistiche:la situazione nei macrosettori Economico Aziendale e Statistico
2019
La prima parte del mio intervento, corredata da grafici e da tabelle, riguarda non soltanto le aree dei non bibliometrici, ma la valutazione in generale. Come è noto ogni prodotto scientifico è stato valutato secondi i seguenti parametri qualitativo-numerici: eccellente (1), elevato (0,7), discreto (0,4), accettabile (0,1), limitato (0). Da tutte le valutazioni espresse dai vari GEV per i prodotti conferiti dalle aree scientifiche, è stato ricavato, per ognuno dei Settori Disciplinari, un punteggio medio che tiene conto dei risultati a livello nazionale.
Weighted and unweighted distances based decision tree for ranking data
2018
Preference data represent a particular type of ranking data (widely used in sports, web search, social sciences), where a group of people gives their preferences over a set of alternatives. Within this framework, distance-based decision trees represent a non-parametric tool for identifying the profiles of subjects giving a similar ranking. This paper aims at detecting, in the framework of (complete and incomplete) ranking data, the impact of the differently structured weighted distances for building decision trees. The traditional metrics between rankings don’t take into account the importance of swapping elements similar among them (element weights) or elements belonging to the top (or to …
Multidimensional scaling and stock location assignment in a warehouse: an application
1999
By means of an application, in the present paper, the suitability of a multivariate statistical methodology, as multidimensional scaling (MDS), to solve an optimization problem is shown. In particular, considering the stock location assignment problem in the warehouse of a supermarket chain, the solution gained by applying MDS to a set of seven variables is compared with the one obtainable by considering the usual techniques applied in this context. A wide discussion of results is reported.
A Projection Pursuit Algorithm for Preference Data
2018
In the framework of preference rankings, the interest can lie in finding which predictors and which interactions are able to explain the observed preference structures. The last years have seen a remarkable owering of works about the use of decision tree for clustering preference vectors. As a matter of fact, decision trees are useful and intuitive, but they are very unstable: small perturbations bring big changes. This is the reason why it could be necessary to use more stable procedures in order to clustering ranking data. In this work, following the idea of Bolton (2003), a Projection Pursuit (PP) clustering algorithm for preference data will be proposed in order to extract useful inform…
DISTANCE‐BASED DECISION TREES FOR RANKING DATA: THE ROLE OF THE WEIGHT SYSTEMS
2018
In everyday life ranking and classification are basic cognitive skills that people use in order to grade everything that they experience. Grouping and ordering a set of elements is considered easy and communicative; thus, rankings of sport‐teams, universities, countries and so on are often observed. A particular case of ranking data is represented by preference data, where individuals show their preferences over a set of items. When individuals specific characteristics are available, an important issue concerns the identification of the profiles of respondents (or judges) giving the same/similar rankings. In order to incorporate respondent‐specific covariates distance‐based decision tree mo…
Mapping the relation between University access test and student’s university performance
2018
The access test is the most used tool to evaluate the initial preparation of an italian student before enrolling at the university. Although the necessity to select the most deserving students seem unquestionably reasonable, we have to wonder if it appears to be a good predictor of university performance. In order to answer this question, the university careers of the students enrolled at two Degree Courses at the University of Palermo (academic year 2013/2014) were analysed. The very aim of this paper is to propose a graphical tool, the Student Efficiency Nomogram, that shows the access test scores together with the first-year performance of the student.