Search results for "Variable"
showing 10 items of 1674 documents
Successful SME web design through consumer focus groups
2011
Purpose – The purpose of this research is to pursue two major objectives. First, to identify the key design variables for building successful transactional SME (Small Medium Enterprises) websites. Second, the transactional relevance of each key design variable is tested in order to establish priorities.Design/methodology/approach – The present paper is developed through seven consumer focus groups. Two approaches were used: an ethnographic summary of each focus group (qualitative approach) and a systematic coding procedure (quantitative approach).Findings – The findings indicate that a transactional website should have three main strong points: it must be secure; price information should be…
Why Do Teachers Use Game-Based Learning Technologies? The Role of Individual and Institutional ICT Readiness
2015
This paper investigates how different individual and institutional factors pertaining to ICT readiness influence teachers’ adoption of game-based learning technologies. The data were gathered from Finnish primary, lower secondary and upper secondary school teachers (N=1668) with an online survey. The results indicate that openness towards ICT, ICT attitude and the ICT compatibility with teaching positively influence the perceived value whereas openness towards ICT, supportive organizational ICT culture, ICT selfefficacy and ICT compatibility with teaching positively influenced the actual use of game-based learning technologies. However, the structural model could explain only little of the …
Applying differential geometric LARS algorithm to ultra-high dimensional feature space
2009
Variable selection is fundamental in high-dimensional statistical modeling. Many techniques to select relevant variables in generalized linear models are based on a penalized likelihood approach. In a recent paper, Fan and Lv (2008) proposed a sure independent screening (SIS) method to select relevant variables in a linear regression model defined on a ultrahigh dimensional feature space. Aim of this paper is to define a generalization of the SIS method for generalized linear models based on a differential geometric approach.
Induced smoothing in LASSO regression
The thesis is being carried out with the National research Council at the Institute of Biomedicine and Molecular Immunology "Alberto Monroy" of Palermo, where I am a fellow, under the supervision of MD Stefania La Grutta. Our research unit is focused on clinical research in allergic respiratory problems in children. In particular, we are interested in to assess the determinants of impaired lung function in a sample of outpatient asthmatic children aged between 5 and 17 years enrolled from 2011 to 2017. Our dataset is composed by n = 529 children and several covariates regarding host and environmental factors. This thesis focuses on hypothesis testing in lasso regression, when one is interes…
Bryophytes of Europe Traits (BET) dataset
2023
The Bryophytes of Europe Traits (BET) dataset includes values for 65 biological and ecological traits and 25 bioclimatic variables for all 1816 bryophytes included in the European Red List (Hodgetts et al. 2019). The traits are compiled from several regional trait datasets and manually complemented using Floras, species-specific literature and expert knowledge. The bioclimatic variables are calculated using the European range of each species. Details regarding the trait compilation and extraction of bioclimatic variables can be found in the corresponding data paper (Van Zuijlen et al. 2023).
The Effect of Public Education Expenditure on Shadow Economy: A Cross-Country Analysis
2015
AbstractThis paper empirically examines whether devoting more resources to education can reduce the size of the shadow economy on a cross-section of countries. The findings show a negative relationship between public education expenditure and the size of the shadow economy, which is robust to the inclusion of different proxies for the control variables, a large set of policy variables, regional differences and endogeneity. The findings also emphasize the role of education, suggesting that public policies devoted to higher education level imply a decreasing effect on the shadow economy.
Post-Enlargement Return Migrants' Earnings Premium: Evidence from Latvia
2008
The paper exploits a recent survey of over ten thousand economically active residents of Latvia; about 5% of respondents have worked abroad over the last three years, while 12% have family members with such experience. Post-enlargement labor migration from Latvia has been predominantly low-skilled, yet return migrants when compared to stayers are, on average, more educated and less likely to work as unskilled manuals. We combine instrumental variable and propensity score matching methods to study the effect of foreign experience on earnings. Results suggest that return migrants are neither positively nor negatively selected in terms of earnings. However, after controlling for worker demogra…
Institutions, Incentives and Trade Union Membership
1997
The study investigates the determinants of unionization in a country — Finland — where union density, defined as the number of unionized members divided by the labour force, has risen 60 percentage points in 32 years, from 22 percent in 1960 to 82 percent in 1992. The theoretical framework of the study is based on the background information obtained from surveys inquiring why individuals join a union. The empirical analysis for the period 1962–92 shows that the model is capable of explaining long-run trends in union density in a very satisfactory manner. The results imply that institutional features of the labour market, characterized by the benefit mark-up variable and a dummy variable cap…
Efficient and accurate computation of Green's function for the Poisson equation in rectangular waveguides
2009
[1] In this paper, a new algorithm for the fast and precise computation of Green's function for the 2-D Poisson equation in rectangular waveguides is presented. For this purpose, Green's function is written in terms of Jacobian elliptic functions involving complex arguments. A new algorithm for the fast and accurate evaluation of such Green's function is detailed. The main benefit of this algorithm is successfully shown within the frame of the Boundary Integral Resonant Mode Expansion method, where a substantial reduction of the computational effort related to the evaluation of the cited Green's function is obtained.
Transport and magnetic properties of La1−xCaxMnO3-films (0.1<x<0.9)
2000
Abstract By laser ablation we prepared thin films of the colossal magnetoresistive compound La1−xCaxMnO3 with doping levels 0.1 10 13 Ω have been measured with an electrometer setup. While the transport data indicate polaronic transport for the metallic samples above the Curie temperature the low-doped ferromagnetic insulating samples show a variable range hopping like transport at low-temperature.