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Farm tourism: a cross-country empirical study in Germany and ItalySidali, Katia Laura <1974> 12 June 2009 (has links)
PROBLEM
In the last few years farm tourism or agritourism as it is also referred to has enjoyed increasing success because of its generally acknowledged role as a promoter of economic and social development of rural areas. As a consequence, a plethora of studies have been dedicated to this tourist sector, focusing on a variety of issues. Nevertheless, despite the difficulties of many farmers to orient their business towards potential customers, the contribution of the marketing literature has been moderate.
PURPOSE
This dissertation builds upon studies which advocate the necessity of farm tourism to innovate itself according to the increasingly demanding needs of customers. Henceforth, the purpose of this dissertation is to critically evaluate the level of professionalism reached in the farm tourism market within a marketing approach.
METHODOLOGY
This dissertation is a cross-country perspective incorporating the marketing of farm tourism studied in Germany and Italy. Hence, the marketing channels of this tourist sector are examined both from the supply and the demand side by means of five exploratory studies. The data collection has been conducted in the timeframe of 2006 to 2009 in manifold ways (online survey, catalogues of industry associations, face-to-face interviews, etc.) according to the purpose of the research of each study project. The data have been analyzed using multivariate statistical analysis.
FINDINGS
A comprehensive literature review provides the state of the art of the main differences and similarities of farm tourism in the two countries of study. The main findings contained in the empirical chapters provide insights on many aspects of agritourism including how the expectations of farm operators and customers differ, which development scenarios of farm tourism are more likely to meet individuals’ needs, how new technologies can impact the demand for farm tourism, etc.
ORIGINALITY/VALUE
The value of this study is in the investigation of the process by which farmers’ participation in the development of this sector intersects with consumer consumption patterns. Focusing on this process should allow farm operators and others including related businesses to more efficiently allocate resources.
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Modelli non lineari statici e dinamici su dati microeconomici: analisi delle condizioni finanziarie delle famiglie italianeGiarda, Elena <1968> 23 March 2010 (has links)
The thesis studies the economic and financial conditions of Italian households, by using microeconomic data of the Survey on Household Income and Wealth (SHIW) over the period 1998-2006. It develops along two lines of enquiry. First it studies the determinants of households holdings of assets and liabilities and estimates their correlation degree. After a review of the literature, it estimates two non-linear multivariate models on the interactions between assets and liabilities with repeated cross-sections. Second, it analyses households financial difficulties. It defines a quantitative measure of financial distress and tests, by means of non-linear dynamic probit models, whether the probability of experiencing financial difficulties is persistent over time.
Chapter 1 provides a critical review of the theoretical and empirical literature on the estimation of assets and liabilities holdings, on their interactions and on households net wealth. The review stresses the fact that a large part of the literature explain households debt holdings as a function, among others, of net wealth, an assumption that runs into possible endogeneity problems.
Chapter 2 defines two non-linear multivariate models to study the interactions between assets and liabilities held by Italian households. Estimation refers to a pooling of cross-sections of SHIW. The first model is a bivariate tobit that estimates factors affecting assets and liabilities and their degree of correlation with results coherent with theoretical expectations. To tackle the presence of non normality and heteroskedasticity in the error term, generating non consistent tobit estimators, semi-parametric estimates are provided that confirm the results of the tobit model. The second model is a quadrivariate probit on three different assets (safe, risky and real) and total liabilities; the results show the expected patterns of interdependence suggested by theoretical considerations.
Chapter 3 reviews the methodologies for estimating non-linear dynamic panel data models, drawing attention to the problems to be dealt with to obtain consistent estimators. Specific attention is given to the initial condition problem raised by the inclusion of the lagged dependent variable in the set of explanatory variables. The advantage of using dynamic panel data models lies in the fact that they allow to simultaneously account for true state dependence, via the lagged variable, and unobserved heterogeneity via individual effects specification.
Chapter 4 applies the models reviewed in Chapter 3 to analyse financial difficulties of Italian households, by using information on net wealth as provided in the panel component of the SHIW. The aim is to test whether households persistently experience financial difficulties over time. A thorough discussion is provided of the alternative approaches proposed by the literature (subjective/qualitative indicators versus quantitative indexes) to identify households in financial distress. Households in financial difficulties are identified as those holding amounts of net wealth lower than the value corresponding to the first quartile of net wealth distribution. Estimation is conducted via four different methods: the pooled probit model, the random effects probit model with exogenous initial conditions, the Heckman model and the recently developed Wooldridge model. Results obtained from all estimators accept the null hypothesis of true state dependence and show that, according with the literature, less sophisticated models, namely the pooled and exogenous models, over-estimate such persistence.
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Valutazione degli incentivi nel sistema delle cure primarie: analisi multilivello attraverso modelli logistici e panel con dati di conteggioIezzi, Elisa <1982> 23 March 2010 (has links)
No description available.
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Gli esiti scolastici nelle scuole di secondo grado di Bologna: un'applicazione della teoria dei modelli a curva latenteBorgia, Maria Serena <1972> 08 April 2011 (has links)
Nella presente analisi si è avuta l’eccezionale disponibilità di dati longitudinali su molti individui (6000studenti frequentanti le scuole superiori bolognesi).
Per ottenere un modello che al meglio spiegasse e riproducesse l’andamento degli esiti scolastici (promozione alla classe successiva) tenendo conto del percorso scolastico nel tempo, si è scelto il modello a curva latente condizionato. La variabile risposta è combinazione lineare dell’esito di fine anno (Promosso/Non promosso); riassume, per ogni studente/anno scolastico, classe frequentata ed esito finale. Le variabili esplicative sono state selezionate tra le informazioni disponibili per gli individui.
Vengono presentati alcuni dati aggregati, poi descritti i dati individuali che entreranno nel modello, evidenziando la composizione degli studenti.
La prima fase è la stima del modello logistico, con specificazione delle criticità, che hanno indotto alla scelta successiva del modello dipendente dal tempo.
Dopo la descrizione della metodologia principale utilizzata, la teoria del conditionalLCM, e la selezione degli indicatori di fitting, viene delineata la procedura di stima, e raggiunto il modello ottimale.
Le variabili significative per spiegare l’andamento delle promozioni individuali nel tempo risultano: cittadinanza (italiani con risultati significativamente migliori degli stranieri), sesso (ragazze con percorso scolastico mediamente migliore dei ragazzi: la differenza risulta però significativa soltanto negli istituti tecnici e professionali), tipologia di scuola frequentata (studenti del liceo con risultati significativamente migliori di chi frequenta altri tipi di istituto).
I risultati risultano fortemente dipendenti dai dati impiegati, specie riguardo al limite territoriale. Precedenti analisi evidenziavano una forte differenziazione dei risultati scolastici tra studenti del nord e del sud Italia, oltre che tra studenti dei comuni maggiormente popolati e studenti dei comuni di provincia. Sarebbe interessante disporre di dati individuali analoghi a quelli qui utilizzati, ma riferiti all’intero territorio nazionale, oppure ad un zona maggiormente vasta dell’Italia, onde saggiare l’entità dell’influenza sul percorso scolastico,ed in particolare sulla regolarità, della differenza territoriale.
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A moment symbolic representation of Lévy processes with applicationsOliva, Immacolata <1982> 06 June 2012 (has links)
By using a symbolic method, known in the literature as the classical umbral calculus, a symbolic representation of Lévy processes is given and a new family of time-space harmonic polynomials with respect to such processes, which includes and generalizes the exponential complete Bell polynomials, is introduced.
The usefulness of time-space harmonic polynomials with respect to Lévy processes is that it is a martingale the stochastic process obtained by replacing the indeterminate x of the polynomials with a Lévy process, whereas the Lévy process does not necessarily have this property. Therefore to find such polynomials could be particularly meaningful for applications.
This new family includes Hermite polynomials, time-space harmonic with respect to Brownian motion, Poisson-Charlier polynomials with respect to Poisson processes, Laguerre and actuarial polynomials with respect to Gamma processes , Meixner polynomials of the first kind with respect to Pascal processes, Euler, Bernoulli, Krawtchuk, and pseudo-Narumi polynomials with respect to suitable random walks.
The role played by cumulants is stressed and brought to the light, either in the symbolic representation of Lévy processes and their infinite divisibility property, either in the generalization, via umbral Kailath-Segall formula, of the well-known formulae giving elementary symmetric polynomials in terms of power sum symmetric polynomials.
The expression of the family of time-space harmonic polynomials here introduced has some connections with the so-called moment representation of various families of multivariate polynomials. Such moment representation has been studied here for the first time in connection with the time-space harmonic property with respect to suitable symbolic multivariate Lévy processes. In particular, multivariate Hermite polynomials and their properties have been studied in connection with a symbolic version of the multivariate Brownian motion, while multivariate Bernoulli and Euler polynomials are represented as powers of multivariate polynomials which are time-space harmonic with respect to suitable multivariate Lévy processes.
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Modelli Gravitazionali per l'analisi del Commercio Internazionale / Spatial Gravity Models for Internationsl Trade analysisMetulini, Rodolfo <1983> 12 February 2013 (has links)
Il modello gravitazionale e' ormai diventato un "cavallo da battaglia" in economia internazionle ed e' comunemente utilizzato nella determinazione dei flussi commerciali. Recentemente, molti studi hanno mostrato l'importanza della dipendenza spaziale, che va' a considerare quegli effetti dovuti al cosiddetto "third country". Intervengono a questo scopo la modellistica e le tecniche di stima di Econometria Spaziale. Verra' fatto uso di tali tecniche allo scopo di stimare con un modello gravitazionale spaziale il commercio internazionale tra paesi dell'OCSE per un panel di 22 anni.
L'obiettivo e' quindi duplice: da un lato, si andra' ad applicare le piu' moderne tecniche di Econometria Spaziale, in un campo in cui tali contributi scarseggiano. Dall'altro lato,verra' fornita una interpretazione del comportamento del commercio internazionale tra paesi dell'OCSE, approfondendo gli aspetti relativi all'effetto del"third country" e del fenomeno migratorio. Inoltre , viene proposta un'analisi che ha lo scopo di validare l'ipotesi di omissione della distanza dal modello gravitazione strutturale. / The Gravity Model is the "workhorse for empirical studies" in International Economies and it is commonly used in explaining the trade flow between countries. Recently, several studies have showed the importance of taking into account the spatial effect. Spatial Econometric techniques meet this matter, proposing the specification of a set of models and estimators. We will make use of these Spatial Econometric techniques in order to estimate a Spatial Gravity of Trade for a 22-year-long panel of the OECD countries. The aim, therefore, is twofold: on one hand, we are going to use the newest Spatial Econometric techniques in a field where they aren't widely applicated. On the other hand, we provide an updated interpretation of the behaviour of the International Trade in an OECD context, going deeply on the explanation of the spatial spillover effect due to the third country dependence, and of the migratory phenomenon. Moreover, we propose an economically-based analysis whose aim is to avoid the use of the "distance" variable in the Gravity Model. The empirical results confirm the importance of taking into account the spatial dependence and they allow us to estimate the model wirhout the "distance", if properly replaced by a set of fixed effects.
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La Previsione dei Consumi Elettrici nel Mercato Energetico Italiano : un nuovo modello empirico con struttura triangolare / Forecasting Electricity Consumption in the Italian Energy Market : Results from a novel empirical modelMazzoni, Franco <1982> 12 February 2013 (has links)
L'obiettivo principale della tesi è lo sviluppo di un modello empirico previsivo di breve periodo che sia in grado di offrire previsioni precise ed affidabili dei consumi di energia elettrica su base oraria del mercato italiano. Questo modello riassume le conoscenze acquisite e l'esperienza fatta durante la mia attuale attività lavorativa presso il Romagna Energia S.C.p.A., uno dei maggiori player italiani del mercato energetico.
Durante l'ultimo ventennio vi sono stati drastici cambiamenti alla struttura del mercato elettrico in tutto il mondo. Nella maggior parte dei paesi industrializzati il settore dell'energia elettrica ha modificato la sua originale conformazione di monopolio in mercato competitivo liberalizzato, dove i consumatori hanno la libertà di scegliere il proprio fornitore.
La modellazione e la previsione della serie storica dei consumi di energia elettrica hanno quindi assunto un ruolo molto importante nel mercato, sia per i policy makers che per gli operatori.
Basandosi sulla letteratura già esistente, sfruttando le conoscenze acquisite 'sul campo' ed alcune intuizioni, si è analizzata e sviluppata una struttura modellistica di tipo triangolare, del tutto innovativa in questo ambito di ricerca, suggerita proprio dal meccanismo fisico attraverso il quale l'energia elettrica viene prodotta e consumata nell'arco delle 24 ore. Questo schema triangolare può essere visto come un particolare modello VARMA e possiede una duplice utilità, dal punto di vista interpretativo del fenomeno da una parte, e previsivo dall'altra. Vengono inoltre introdotti nuovi leading indicators legati a fattori meteorologici, con l'intento di migliorare le performance previsive dello stesso.
Utilizzando quindi la serie storica dei consumi di energia elettrica italiana, dall'1 Marzo 2010 al 30 Marzo 2012, sono stati stimati i parametri del modello dello schema previsivo proposto e valutati i risultati previsivi per il periodo dall'1 Aprile 2012 al 30 Aprile 2012, confrontandoli con quelli forniti da fonti ufficiali. / The subject of this thesis is forecasting daily electricity consumption in Italy, at an hourly basis. The analyses presented in this work summarize my working experience at Romagna Energia S.c.P.A.
Although several approaches have been proposed in the last two decades, forecasting energy consumption is a recent research subject, especially as concerns the Italian case.
Historically, the power sector was characterized by a highly vertically integrated market structure with limited competition. However, during the last two decades, revolutionary changes to the structure of the electricity business have taken place around the world. The electric power industry in many countries all over the world is moving from a centralized operational approach to a liberalized one. Italy makes not exception.
Modeling and predicting electricity consumption play an important role in developed and developing countries for policy makers and related organizations.
In this thesis I provide a twofold contribution.
First, I examine in detail the institutional features of the Italian Energy Market and its stylized facts.
Second, since electricity prices are formed at an hourly basis, I focus on daily
load dynamics at hourly frequency and propose a novel time series empirical
forecasting model which:
• features a ‘triangular scheme’, i.e. a VARMA-type structure which is suggested by the physical mechanism through which electricity is produced and delivered
over the 24 hours which allows one to exploit the possible inefficiencies
that might characterize the grid;
• includes new leading indicators related to weather conditions.
The sample used for parameters estimation is the time series of italian electricity consumptions from March 1st, 2010 to March 31st, 2012, corresponding to 18285 observations.
Finally, the forecasting models results for the load of April, 2012, are compared with the official Italian authority forecast.
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Multidimensional Measures of Firm Competitiveness: a Model-Based ApproachDonno, Annalisa <1983> 12 February 2013 (has links)
The concept of competitiveness, for a long time considered as strictly connected to economic and financial performances, evolved, above all in recent years, toward new, wider interpretations disclosing its multidimensional nature.
The shift to a multidimensional view of the phenomenon has excited an intense debate involving theoretical reflections on the features characterizing it, as well as methodological considerations on its assessment and measurement.
The present research has a twofold objective: going in depth with the study of tangible and intangible aspect characterizing multidimensional competitive phenomena by assuming a micro-level point of view, and measuring competitiveness through a model-based approach.
Specifically, we propose a non-parametric approach to Structural Equation Models techniques for the computation of multidimensional composite measures.
Structural Equation Models tools will be used for the development of the empirical application on the italian case: a model based micro-level competitiveness indicator for the measurement of the phenomenon on a large sample of Italian small and medium enterprises will be constructed.
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Multilevel Analysis in Household Survey: An Application to Health Condition Data / Analisi multilivello nelle indagini sulle famiglie: una applicazione ai dati sulle condizioni di salutePiombo, Sara <1969> 25 February 2013 (has links)
The aim of this thesis is to apply multilevel regression model in context of household surveys. Hierarchical structure in this type of data is characterized by many small groups. In last years comparative and multilevel analysis in the field of perceived health have grown in size. The purpose of this thesis is to develop a multilevel analysis with three level of hierarchy for Physical Component Summary outcome to: evaluate magnitude of within and between variance at each level (individual, household and municipality); explore which covariates affect on perceived physical health at each level; compare model-based and design-based approach in order to establish informativeness of sampling design; estimate a quantile regression for hierarchical data. The target population are the Italian residents aged 18 years and older. Our study shows a high degree of homogeneity within level 1 units belonging from the same group, with an intraclass correlation of 27% in a level-2 null model. Almost all variance is explained by level 1 covariates. In
fact, in our model the explanatory variables having more impact on the outcome
are disability, unable to work, age and chronic diseases (18 pathologies). An additional analysis are performed by using novel procedure of analysis :"Linear Quantile Mixed Model", named "Multilevel Linear Quantile Regression", estimate. This give us the possibility to describe more generally the conditional distribution of the response through the estimation of its quantiles, while accounting for the dependence among the observations. This has represented a great advantage of our models with respect to classic multilevel regression. The median regression with random effects reveals to be more efficient than the mean regression in representation of the outcome central tendency. A more detailed analysis of the conditional distribution of the response on other quantiles highlighted a differential effect of some covariate along the distribution. / Lo scopo di questa tesi è quello di applicare il modello di regressione multilivello nel contesto di indagini sulle famiglie. La struttura gerarchica in questo tipo di dati è caratterizzato da numerosi piccoli gruppi. Negli ultimi anni analisi comparative e multilivello sullo stato di salute percepito sono aumentate molto. L’obiettivo di questa tesi è di applicare un'analisi multilivello a tre livelli per la variabile risposta Physical Component Summary allo scopo di: valutare entità all'interno e tra varianza ad ogni livello (individuale, familiare e comune); indagare quali covariate influiscono sulla percezione dello stato di salute fisica ogni livello; confrontare le analisi model-based e di design-based al fine di stabilire se i pesi campionari siano informativiti per il modello di interesse; stimare una regressione quantile per i dati gerarchici. La popolazione target sono i residenti italiani di età compresa tra 18 anni. Il nostro studio rileva un’elevata omogeneità tra le unità di livello 1 e una correlazione intraclasse del 27% nel modello nullo a 2livelli. Quasi tutta la varianza è spiegata dalle covariate di livello. Nel nostro modello le variabili esplicative hanno un impatto maggiore sulla variabile risposta sono la disabilità, inabilità al lavoro, l’età e le malattie croniche (18 patologie). Un'ulteriore analisi viene eseguita utilizzando una nuova procedura di analisi: "Regressione lineare quantile multilivello”. Questa analisi ci dà la possibilità di descrivere più in generale la distribuzione condizionata della variabile risposta attraverso la stima dei suoi quantili. Questo ha portato un grande vantaggio nei nostri modelli rispetto al classico modello di regressione multilivello. La regressione mediana con effetti casuali si rivela più efficiente del regressione media nella rappresentazione della tendenza centrale. Un'analisi più dettagliata della distribuzione condizionata della variabile risposta in corrispondenza di altri quantili ha evidenziato che certe covariate hanno un effetto diverso lungo la distribuzione.
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In defence of modeling simultaneity for a correct approximation of cultural aspects: implications for food consumers studies with latent variablesVassallo, Marco <1971> 04 July 2013 (has links)
Dealing with latent constructs (loaded by reflective and congeneric measures) cross-culturally compared means studying how these unobserved variables vary, and/or covary each other, after controlling for possibly disturbing cultural forces. This yields to the so-called ‘measurement invariance’ matter that refers to the extent to which data collected by the same multi-item measurement instrument (i.e., self-reported questionnaire of items underlying common latent constructs) are comparable across different cultural environments. As a matter of fact, it would be unthinkable exploring latent variables heterogeneity (e.g., latent means; latent levels of deviations from the means (i.e., latent variances), latent levels of shared variation from the respective means (i.e., latent covariances), levels of magnitude of structural path coefficients with regard to causal relations among latent variables) across different populations without controlling for cultural bias in the underlying measures. Furthermore, it would be unrealistic to assess this latter correction without using a framework that is able to take into account all these potential cultural biases across populations simultaneously. Since the real world ‘acts’ in a simultaneous way as well. As a consequence, I, as researcher, may want to control for cultural forces hypothesizing they are all acting at the same time throughout groups of comparison and therefore examining if they are inflating or suppressing my new estimations with hierarchical nested constraints on the original estimated parameters. Multi Sample Structural Equation Modeling-based Confirmatory Factor Analysis (MS-SEM-based CFA) still represents a dominant and flexible statistical framework to work out this potential cultural bias in a simultaneous way. With this dissertation I wanted to make an attempt to introduce new viewpoints on measurement invariance handled under covariance-based SEM framework by means of a consumer behavior modeling application on functional food choices.
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