Search results for "Statistic"

Like Parents, like Teenagers: A Romanian Youth Smoking Overview

2015

AbstractThis paper estimates how family model influences youth's smoking behaviors and describes smoking behavior in Romania nowadays. A questionnaire-based survey was used and data was collected from a national sample (1,364 people: 536 male and 828 female; average age 22,71 years and SD=3,128). The paper analyses only the items relevant for smoking behavior.Using a quasi-experimental design, we found a significant difference determinated by father's model (ρ(1364)= 0,158, p < 0,05), mother's model (ρ(1362)=0,155, p < 0,05), and brothers/sisters’ model (ρ(1362)=0,219, p < 0,05), regarding smoking behavior.Keywords: smoking behaviour, Romanian teenagers, parental model, Health Psychology

Experimental Engineering of Arbitrary Qudit States with Discrete-Time Quantum Walks

2019

The capability to generate and manipulate quantum states in high-dimensional Hilbert spaces is a crucial step for the development of quantum technologies, from quantum communication to quantum computation. One-dimensional quantum walk dynamics represents a valid tool in the task of engineering arbitrary quantum states. Here we affirm such potential in a linear-optics platform that realizes discrete-time quantum walks in the orbital angular momentum degree of freedom of photons. Different classes of relevant qudit states in a six-dimensional space are prepared and measured, confirming the feasibility of the protocol. Our results represent a further investigation of quantum walk dynamics in p…

Applications of Microlocal Analysis in Inverse Problems

2020

This note reviews certain classical applications of microlocal analysis in inverse problems. The text is based on lecture notes for a postgraduate level minicourse on applications of microlocal analysis in inverse problems, given in Helsinki and Shanghai in June 2019.

Global Estimation of Biophysical Variables from Google Earth Engine Platform

2018

This paper proposes a processing chain for the derivation of global Leaf Area Index (LAI), Fraction of Absorbed Photosynthetically Active Radiation (FAPAR), Fraction Vegetation Cover (FVC), and Canopy water content (CWC) maps from 15-years of MODIS data exploiting the capabilities of the Google Earth Engine (GEE) cloud platform. The retrieval chain is based on a hybrid method inverting the PROSAIL radiative transfer model (RTM) with Random forests (RF) regression. A major feature of this work is the implementation of a retrieval chain exploiting the GEE capabilities using global and climate data records (CDR) of both MODIS surface reflectance and LAI/FAPAR datasets allowing the global estim…

ENSEMBLE METHODS FOR RANKING DATA

2017

The last years have seen a remarkable flowering of works about the use of decision trees for ranking data. 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, as ensemble methods, in order to find which predictors are able to explain the preference structure. In this work ensemble methods as BAGGING and Random Forest are proposed, from both a theoretical and computational point of view, for deriving classification trees when ranking data are observed. The advantages of these procedures are shown through an example on the SUSHI data set.

Ensemble methods for ranking data with and without position weights

2020

The main goal of this Thesis is to build suitable Ensemble Methods for ranking data with weights assigned to the items’positions, in the cases of rankings with and without ties. The Thesis begins with the definition of a new rank correlation coefficient, able to take into account the importance of items’position. Inspired by the rank correlation coefficient, τ x , proposed by Emond and Mason (2002) for unweighted rankings and the weighted Kemeny distance proposed by García-Lapresta and Pérez-Román (2010), this work proposes τ x w , a new rank correlation coefficient corresponding to the weighted Kemeny distance. The new coefficient is analized analitically and empirically and represents the main…

Il confronto fra dati nel tempo: i numeri indice

2009

Italian University student evaluation of teaching: does it changes over time?

2010

This paper concerns the measurement of the Student Evaluation of Teaching (SET) by undergraduates. For almost 15 years Italian Universities have been monitoring that aspect, performing on students’ opinions about teaching, e.g. on teacher punctuality, clearness and willingness, and on suitability of the facility, logistics, and on course scheduling and managing. Each University carries out a survey with own procedures and through a questionnaire consisting of two set of items: a set of items equal for all Italian Universities, and a set of items built by each University. The survey basic aim is to gather information on teaching skill, educational goals, coordination among teachings, and ade…

Il ruolo della comprensione del testo nel processo di matematizzazione e modellizzazione

2017

In questo articolo vengono analizzate le risposte fornite a un interessante item relativo alla Prova standardizzata di matematica somministrata nel maggio 2015 a tutti gli allievi di quinta elementare del Canton Ticino. A partire dai risultati statistici emersi da un campione di 508 protocolli selezionati, viene presentata un’analisi qualitativa effettuata su un campione più ristretto di 174 studenti di prima media, allo scopo di rintracciare le cause delle difficoltà emerse nella risoluzione. Da questa analisi si rileva come le risposte sbagliate di diversi studenti siano legate a difficoltà nella comprensione del testo dell’item, in particolare a difficoltà di interpretazione linguistica.…

Differences between students' PISA reading literacy scores and grading for mother tongue and literature at school : A geostatistical analysis of the …

2016

In Finland, the national Core Curriculum for Basic Education defines the learning objectives along with the numerical grade to be given for good competence in each school subject in the final phase of basic education. While serving as a guideline for schools and teachers, it should also ensure an objective evaluation of all students in Finland. In this paper, we take a closer look at the equality of student assessment in Finland in the light of student performance in the Programme for International Student Assessment (PISA) 2009. This study investigates the relationship between the grades given to students in mother tongue and literature at different schools and the same students’ reading l…