Search results for " Bias"
showing 10 items of 437 documents
The MOBI-Kids Study Protocol: Challenges in Assessing Childhood and Adolescent Exposure to Electromagnetic Fields from Wireless Telecommunication Tec…
2014
The rapid increase in mobile phone use in young people has generated concern about possible health effects of exposure to radiofrequency (RF) and extremely low frequency (ELF) electromagnetic fields (EMF). MOBI-Kids, a multinational case–control study, investigates the potential effects of childhood and adolescent exposure to EMF from mobile communications technologies on brain tumor risk in 14 countries. The study, which aims to include approximately 1,000 brain tumor cases aged 10–24 years and two individually matched controls for each case, follows a common protocol and builds upon the methodological experience of the INTERPHONE study. The design and conduct of a study on EMF exposure an…
Bodies in the early childhood education classroom: a Bourdieusian analysis of curricular materials
2019
To our knowledge, no studies have used Bourdieu's theoretical contributions to frame investigations on how early childhood education (ECE) teaching materials construct body differences in a way that justifies gender inequality. For Bourdieu, the power to classify and grant properties and signs to subjects, does not reside only in the power to impose, but also in the degree to which the vision is anchored within reality. Therefore, the aims of this study is to assess the representation of the body in the curricular materials of ECE classrooms in 10 public centers, by means of quantitative content analysis and to provide, using Pierre Bourdieu's theoretical framework on the construction of th…
Are private schools more efficient than public schools ? Evidence from Tanzania
2001
International audience; Beginning in the mid-1980s, there has been an explosive growth of private secondary schools in Tanzania. By easing constraints on private operators, the government has clearly found an effective way in the context of right public budget constraints to cope with the excess demand for this level of schooling. But has the policy also led to efficient operations in terms of student learning ? In this paper, we attempt to shed light on this issue by comparing the efficiency of four types of schools that make up the majority of schools in the country : Government and Community schools in the public sector, and Chirstian and Wazazi schools in the private sector. Using longi…
Trade Costs, Trade Balances, and Current Accounts: an application of Gravity to Multilateral Trade
2005
In this paper we test the well-known hypothesis of Obstfeld and Rogoff (NBER Macroeconomics Annual 7777:339–390, 2000) that trade costs are the key to explaining the so-called Feldstein–Horioka puzzle. Our approach has a number of novel features. First, we focus on the interrelationship between trade costs, the trade account and the Feldstein–Horioka puzzle. Second, we use the gravity model to estimate the effect of trade costs on bilateral trade and, third, we show how bilateral trade can be used to draw inferences about desired trade balances and desired intertemporal trade. Our econometric results provide strong support for the Obstfeld and Rogoff hypothesis and we are also able to recon…
Asymmetric decentralisation, economic cycle, regional and local government’s borrowing in Spain
2014
This paper investigates the evolution of sub-central government borrowing in Spain over the period 1996–2011. The arguments and figures provided show that the intense process of political and fiscal decentralisation that took place over the 1990s and 2000s did not lead to higher debt ratios in terms of GDP at these tiers of government until 2007. Although a kind of overspending bias was in effect until the late 2000s, the paper shows that the evolution of GDP and tax revenues provided regional and local governments with enough resources to vigorously pursue their devolved public policy responsibilities and still keep their debt ratios under control. However, since 2008, when the world finan…
TESTING FOR CONTAGION: A CONDITIONAL CORRELATION ANALYSIS
2005
Abstract In this paper, we test for contagion within the East Asian region, contagion being defined as a significant increase in the degree of comovement between stock returns in different countries. For this purpose, we use a parameter stability test, and, following [Rigobon, R., 2003a. On the measurement of the international propagation of shocks: is the transmission stable?, Journal of International Economics], we control for three types of bias, resulting from heteroscedasticity, endogeneity and omitted variable, respectively. The null of interdependence against the alternative of contagion is then tested as an overidentifying restriction. Unlike other studies, our approach is based on …
The Consistency of Fairness Rules: An Experimental Study
2010
In the last two decades, experimental papers on distributive justice have abounded. Two main results have been replicated. Firstly, there is a multiplicity of fairness rules. Secondly, fairness decisions differ depending on the context. This paper studies individual consistency in the use of fairness rules, as well as the structural factors that lead people to be inconsistent. We use a within-subject design, which allows us to compare individual behavior when the context changes. In line with the literature, we find a multiplicity of fairness rules. However, when we control for consistency, the set of fairness rules is considerably smaller. Only selfishness and strict egalitarianism seem to…
Volatility co-movements: a time-scale decomposition analysis
2015
In this paper, we are interested in detecting contagion from US to European stock market volatilities in the period immediately after the Lehman Brothers collapse. The analysis is based on a factor decomposition of the covariance matrix, in the time and frequency domain, using wavelets. The analysis aims to disentangle two components of volatility contagion (anticipated and unanticipated by the market). Once we focus on standardized factor loadings, the results show no evidence of contagion (from the US) in market expectations (coming from implied volatility) and evidence of unanticipated contagion (coming from the volatility risk premium) for almost any European country. Finally, the estim…
The Simpson paradox of school grading in Italy
2009
Abstract Data from the 2003 OECD-PISA Survey for Italy reveal a striking difference in the relationship between students’ competence (as measured by PISA score in Mathematics) and school grades across regions: a competence level granting bare sufficiency in the North yields excellence grades in the South. This has spurred a lively debate on education policy in the country, based on the inference drawn from this evidence that grading practices are excessively different in the two areas. We show in this note that this inference overlooks a Simpson paradox hidden in the data. After a more careful analysis, the above inference is seen to be wrong. The crucial omitted variable is the school-leve…
Aggregate uncertainty and sectoral productivity growth: The role of credit constraints
2016
Abstract We show that an increase in aggregate uncertainty—measured by stock market volatility—reduces productivity growth more in industries that depend heavily on external finance. The mechanism at play is that during periods of high uncertainty, firms that are credit constrained switch the composition of investment by reducing productivity-enhancing investment—such as on ICT capital—which is more subject to liquidity risks (Aghion et al., 2010). The effect is larger during recessions, when financing constraints are more likely to be binding, than during expansions. Our statistical method—a difference-in-difference approach using productivity growth of 25 industries from 18 advanced econo…