1,720,990 research outputs found
Design and Result of a Statistical Survey in a School
No full textAbstract. The competition between different schools in the same area and the required quality standards necessary to be rated in a satisfactory way by the National Ministry of Education, imposes to schools the activation of self assessment instruments to monitor the activities and the degree of customer satisfaction. In particular it is crucial to measure the customer satisfaction related to the “Piano dell’Offerta Formativa” (P.O.F.), a document describing pedagogical, organizational and managerial choices of the school, the educational aims, the general objectives related to teaching activities and the resources provided to achieve them. To this purpose, were designed and implemented a set of Questionnaires to be filled by students and a parents’ pool was selected via a stratified random sampling process to improve their response rate. The present paper propose to a broad audience the applied approach, since a good data quality was achieved with this survey, and weak and strong points of the school was highlighted. Descriptive statistics, as frequencies and means, were used to summarize questionnaire responses. A logistic regression analysis has been performed to model the relationship between a binary outcome as students’ attendance/not attendance to a specific school activity and some explanatory variables concerning school welcoming, relations, learning, teaching and involvement recognition
Valutazione del rischio di default delle PMI attraverso uno studio caso-controllo
No full textObiettivo di questo lavoro è proporre un processo di sviluppo di un modello statistico rigoroso per la valutazione del rischio di credito. Il lavoro è volto ad individuare la capacità predittiva degli indici di bilancio e indicare quale sottoinsieme sia in grado di misurare più accuratamente lo stato di salute di una azienda. Attraverso uno studio caso-controllo, gli autori propongono un metodo di analisi in grado di individuare le variabili più rilevanti in considerazione delle caratteristiche territoriali e settoriali del campione di analisi. Il lavoro presenta caratteristiche innovative riguardo al metodo di analisi adottato, alla numerosità degli indici analizzati, all’individuazione di un numero ristretto di variabili chiave e alla quantificazione degli effetti delle variazioni degli indici sulla misura della probabilità di default
MANAGEMENT CONTROL SYSTEM AS A PACKAGE AND PERFORMANCE IN THE SMALL AND MEDIUM SIZED ITALIAN MANUFACTURING ENTERPRISES
No full textVariable Selection in Binary Logistic Regression for Modelling Bankruptcy Risk
No full textAbstract. One of the most fascinating areas of study in the current economic
and nancial world is the forecasting of credit risk and the ability
to predict a company's insolvency. Meanwhile, one major challenge in
constructing predictive failure models is variable selection. Standard selection
methods exist alongside new approaches. In addition, the huge
availability of data often implies limitations due to processing time and
new high-performance procedures provide tools that can take advantage
of parallel processing. In the present paper, dierent variable selection
techniques were explored in the context of applying logistic regression
for binary data to a balanced data set including only rms active or
in bankruptcy. Models deriving from stepwise selection, the Least Absolute
Shrinkage and Selection Operator (LASSO) and an unsupervised
method, based on the maximum data variance explained, were compared.
Then a non-parametric approach was considered and the selection of variables
coming from a single decision tree and a forest of trees is compared
and discussed
RISK ANALYSIS AND RETROSPECTIVE UNBALANCED DATA
No full textThis paper considers three different techniques applicable in the context of credit scoring when the event under study is rare and therefore we have to cope with unbalanced data. Logistic regression for matched case-control studies, logistic regression for a random balanced data sample and logistic regression for a sample balanced by ROSE (Random OverSampling Examples, Lunardon, Menardi and Torelli, 2014) are tested. We applied the methods to real data: balance sheets indicators of small and medium-sized enterprises and their legal status are considered. The event of interest is the opening of insolvency proceedings of bankruptcy
La regressione logistica per la previsione del rischio di default degli enti locali italiani. Profili teorici ed evidenze empiriche
No full textIl presente lavoro intende testare l’affidabilità dei modelli econometrici per la previsione del rischio di default degli enti locali. L’obiettivo della ricerca è stato perseguito mediante un approccio metodologico di tipo deduttivo-induttivo. La fase deduttiva ha avuto ad oggetto l’analisi critica della letteratura, nazionale ed internazionale, in materia di crisi finanziaria dell’ente locale e modelli econometrici per la previsione delle crisi aziendali. Nella fase induttiva è stato sviluppato un modello logistico condizionato per studi caso-controllo in cui le variabili esplicative sono costituite da indicatori finanziari costruiti sui dati di bilancio. Il modello è stato testato su un campione casuale stratificato composto da 168 comuni italiani. I risultati dimostrano la validità del Cash Solvency (che misura la capacità di riscossione delle entrate correnti rispetto alle spese correnti), dell’indicatore di Incidenza delle entrate proprie sulle entrate totali e dell’indicatore di Indebitamento (che misura il peso dei debiti sulle entrate totali) come predittori del rischio di default
La capacità predittiva degli indicatori di bilancio: un metodo per le PMI
No full textThe aim of this work is to propose a rigorous statistical procedure to identify which
subset of balance sheet indicators is able to accurately measure the default probability of a
firm and to assess their predictive capacity. Through a case-control study on firms operating
in the Italian region of Umbria, and after performing a matching based on industry and
legal status, the authors propose a statistical procedure of analysis which allows to identify
the most influential variables and then study the functional form linking their effect to the
probability of default. The paper presents innovative features with respect to the number
of indicators considered, the identification of a limited number of key variables and the
quantification of their effect on the default probability
Forecasting Probability of Bankruptcy from unbalanced data
No full textWhen analysing the determinants of bankruptcy of small and medium enterprises, one of the most common problems is that of unbalanced data, as very often the event under study happens in only a small percentage of cases. The aim of this paper is to explore three different statistical methods of coping with unbalanced data and to identify which of these has the greatest predictive capability in the context of the bankrupcty event.
The dataset is composed of all firms which were active in Tuscany in 2006. For each of them we have a five-year series of balance sheet indicators. Bankruptcy is represented by their legal status at May 2010. We focused on some indicators previously identified as predictors of the state of bankruptcy (Pierri 2013; Pierri, Burchi and Stanghellini 2013) and we tested the same model using the following three methods: logistic regression for matched case-control studies, logistic regression for a random balanced data sample, logistic regression for a sample balanced by ROSE (Random OverSampling Examples, Menardi and Torelli 2014). We built a training sample to develop the models and a hold-out sample to compare their discriminatory ability through ROC curves
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
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