Anna Giraldo - Academia.edu (original) (raw)

Papers by Anna Giraldo

All published books are double-blind peer reviewed. The Scientific Committee is responsible of re... more All published books are double-blind peer reviewed. The Scientific Committee is responsible of reviewing processes.

In a CAWI (Computer-Assisted Web Interview) survey self-selection is a potential source of bias, ... more In a CAWI (Computer-Assisted Web Interview) survey self-selection is a potential source of bias, even if it is a census survey. In fact, people who participate in the survey can be very different wit h respect to other eligible units who decided not to answer the questionnaire. A careful contact strategy and some weighting procedures to compensate for non-response, can be used to control bias. In this work we present the efforts made to compens ate for this non-response bias in a CAWI survey conducted in early 2012 on a cohort of 8.473 first-degree course students, enrolled in academic year 2006/07 at Padova University. The survey aimed to investigate students’ attitudes, emotions and motivations towards university studies , and how they use support services. Information about university careers and students’ household characteristics are also collected (see [1]). University administrative archives provided i nformation to contact individuals (university email, private email, phone ...

Advances in Latent Variables Methods Models and Applications, Jun 12, 2013

In the study of university paths both personal and households’ characteristics of the students de... more In the study of university paths both personal and households’ characteristics of the students deeply influence their university outcomes. Students’ attitudes, motivations and emotions towards university study are also very important factors that contribute to explain university achievement. In this work we use a latent class approach to find the underlying latent factors that summarize a series of items investigating different domains of students’ orientations towards university study. Data come from a CAWI survey conducted in 2012 on a cohort of students from Padova University.

The aim of this paper is to investigate the possibility of collecting information on the reproduc... more The aim of this paper is to investigate the possibility of collecting information on the reproductive behaviour of mothers by means of a two-stages data collection procedure. At first stage a simple self-filled questionnaire is administered to a sample of students attending compulsory school; thus, each pupil is asked to give his mother a more complex questionnaire, bringing it back to school. Linking the two questionnaires, the non-response selection problems are solved using the same statistical techniques used to control attrition in panel surveys. Even if selffilled questionnaires can not be too complex, in some cases this data collection procedure can be recommended as (1) the proportion of unit non-responses in standard surveys can be very high, and the unit non-response selection is not easy to control; (2) it is a very low cost data collection procedure. After a general description of this data collection technique, an application is performed using data of the Urban Fertility Survey (UFS) conducted during 2001-02 in four Italian towns. As respondents are clearly selected (e.g., by citizenship) if data analysis is performed without correcting for non-response, results may be biased. In particular, we compare some regression models explaining fertility using data collected by the two questionnaires.

Decision Support Systems, Dec 28, 2012

This work is part of a research project funded by the University of Padova, focusing on the main ... more This work is part of a research project funded by the University of Padova, focusing on the main learning difficulties encountered by university students, and on the most suitable strategies to overcome and/or prevent them. We present an analysis by students cohort and by degree courses using data from the administrative archives of the University of Padova. Our aim was to examine the influence of the contextual characteristics of the degree courses on educational failure/success. The analysis is in two steps. First we use Multipledecrement life tables to describe, by means of survival rates and cumulative decrement rates, levels of withdrawal, change of course and delay, to segment the courses into homogenous groups. Then, by means of hierarchical regression models, we examine the effects of contextual variables which, together with personal characteristics, influence withdrawal.

Giornate Di Studio Sulla Popolazione 2015, Nov 14, 2014

La crisi economica cominciata a fine 2008 ha comportato notevoli cambiamenti nell’organizzazione ... more La crisi economica cominciata a fine 2008 ha comportato notevoli cambiamenti nell’organizzazione delle famiglie italiane. L’alta percentuale di licenziamenti, la disoccupazione giovanile e i bassi salari hanno prodotto nuovi e forse piu precari equilibri al loro interno. E ben noto che l'andamento del ciclo economico si ripercuote sul modo di fare e trasformare la famiglia (si veda, ad esempio, Sobotka et al., 2011; Barbieri et al., 2012; Vignoli et al., 2012; Goldstein et al., 2013). E' altrettanto noto che nei paesi mediterranei ed in Italia in particolare la famiglia agisce come ammortizzatore sociale (si veda Dalla Zuanna, 2001) ed e quindi presumibile che gli effetti della crisi economica siano particolarmente pronunciati. In questo lavoro, intendiamo verificare questa funzione della famiglia come ammortizzatore sociale focalizzandoci proprio sugli anni della crisi economica.

Clinical cancer research : an official journal of the American Association for Cancer Research, 1998

The activation of zymogen and the amount of proteinase and its inhibition are important in determ... more The activation of zymogen and the amount of proteinase and its inhibition are important in determining the eventual activity of matrix-degrading enzymes involved in tumor aggressiveness. To evaluate a gene complement leading to matrix metalloproteinase 2 (MMP-2; Mr 72,000 gelatinase) activity, membrane type 1 MMP (MT1-MMP), urokinase-type plasminogen activator, MMP-2, and tissue inhibitor of metalloproteinase 2 transcriptional levels were measured in gastric carcinoma biopsies. Comparative tumor:normal tissue reverse transcription-PCR in a cohort of 25 patients revealed up to a 10-fold difference in the expression of MT1-MMP, a metalloproteinase that has been proposed as a membrane receptor activator of MMP-2; a 1-unit increment resulted in a 30% risk to survival. A 20% risk also resulted from a 1-unit increment in the MT1-MMP: MMP-2 ratio, which showed differences of up to 15-fold. Instead, the expression of urokinase-type plasminogen activator, which trips off a cascade ending in ...

Evidence from several countries is that any household experiencing poverty today is much more lik... more Evidence from several countries is that any household experiencing poverty today is much more likely to experience it again, which may be due to both unobserved heterogeneity (UH) and true state dependence (TSD). We point out that in this context there are two sources of UH: (1) the household ability to obtain income at a specific time period and (2)

SSRN Electronic Journal, 2013

This paper examines individual and institutional characteristics which may influence the outcomes... more This paper examines individual and institutional characteristics which may influence the outcomes of university students' careers. In particular, it examines the withdrawals, course changes, delays or graduations of students enrolled in first-cycle degree courses in a large public university in NorthEast Italy. Individual longitudinal data from administrative archives were used, taking into account both the temporal dimension in a discrete-time competing risks approach, and the organisational and structural characteristics of the degree courses in which students were enrolled. In order to examine the hierarchical nature of the data properly, analyses were carried out within a multilevel framework. At individual level, results indicate that the profile of a successful student is defined by both socio-demographic factors and pre-university educational experience. At course level, some characteristics such as restricted access to some courses, study fields, and course size were important for students' university careers, although the effects were not always in the expected direction.

SSRN Electronic Journal, 2014

Students' attitudes, motivations and emotions towards university study have a great influence on ... more Students' attitudes, motivations and emotions towards university study have a great influence on their university careers. In this work, we use a latent class factor analysis approach to reveal the underlying latent factors which summarise a series of items investigating students' positions in three domains: self-regulated learning, motivation, and emotions towards university study. Data come from a CAWI survey conducted in 2012 on a cohort of students enrolled in academic year 2006-07 at University of Padova, a large public university in northeast Italy. Results show that the underlying latent factors are in line with related psychological literature.

Compstat, 1994

This paper deals with treatment of missing data in some multidimensional testing problems. Cases ... more This paper deals with treatment of missing data in some multidimensional testing problems. Cases in which missing data are not missing at random are studied. In this context, to obtain valid parametric inferences, the process that causes missing data must be specified. Through a nonparametric approach some problems of missing data not missing at random are discussed and characterized. The proposed solution is based on a nonparametric combination of dependent permutation tests, not requiring any specification of non-response model.

Studies in Higher Education, 2014

The literature has suggested that students' progress at university is influenced by their persona... more The literature has suggested that students' progress at university is influenced by their personal characteristics; this paper examines whether these factors act differently according to the study fields of degree courses in which students are enrolled. In particular, the factors influencing the various outcomes of the university programme (withdrawals, course changes, delays, completion of degrees) in three-year degree courses in a large Italian university are analysed from the perspective of study fields. We examined the records of over 32,000 students enrolling from academic years 2002/03 to 2005/06 in 84 first-cycle degree courses, grouped in four different fields of study. Analyses were conducted by considering the time dimension within the methodological approach of survival analysis, by means of individual longitudinal data from university administrative archives. A discrete-time method for competing risks event history analysis was applied to study the determinants of university outcomes in the various fields of study.