New evidence on the efficiency of Italian airports: A bootstrapped DEA analysis

A bootstrapped DEA procedure is used to estimate technical efficiency of 18 Italian airports during the period 2000-2004. Departing from previous studies, we separate the efficiency related to ability to manage airside activities (operational) from that related to the management of all business activities (financial). In general, Italian airports operate at poor levels of efficiency, with slightly better performance in terms of their financial activities. In the current study, selected intrinsic and environmental characteristics are considered as possible drivers of Italian airport performance. In particular, we found that: (i) the airport dimension does not allows for operational efficiency advantages, (ii) on the other hand, the airport dimension allows for financial efficiency advantages for the case of hubs and disadvantages for the case of the smallest airports (iii) the type(s) of concession agreement(s) might be considered as important source of technical efficiency differentials for those airports running marginal commercial activities; (iv) the introduction of a dual-till price cap regulation might create incentives which lead to the increase of financial efficiency at the detriment of the operational performance. Lastly, the development of a second hub (Milano Malpensa), has negatively affected the performance of the country’s national hub (Roma Fiumicino).     

Parametric Robust Test for Several Variances with Unknown Underlying Distributions

Tsou (in comm Stat-Theor Math 32: 2013–2019, 2003) proposed a parametric robust procedure for testing the equality of two population variances. With large samples the proposed test remains valid under model misspecification. In this article the robust technique is further extended to the comparison of several population variances. More specifically the score test derived on the basis of normal models is adjusted to become robust. The adjusted robust test provides asymptotically valid inference so long as the true underlying distributions have finite fourth moments. Unlike most robust nonparametric approaches, this novel robust technique too provides legitimate variance estimates for estimators of the interested parameters.     

The Relation between Aggregate Earnings and Security Returns over Long Intervals*

This paper provides a theoretical explanation and consistent empirical evidence for the increase in the contemporaneous correlation between returns and aggregate earnings as the return interval is lengthened. Consistent with intuition and with Easton, Harris, and Ohlson 1992, the analysis shows that aggregation over time renders the lag in accounting recognition relatively less important and thus improves the returns‐earnings R². Interestingly, the analysis also reveals that aggregating earnings over longer periods increases the positive covariance between aggregate earnings and the accounting lag, which may further increase the R². This positive covariance can lead to an earnings coefficient greater than one over some range of aggregation, which is consistent with the findings of Easton et al. that over the 10‐year interval the returns‐earnings regression slope coefficient is greater than one (1.7). The empirical results highlight the fact that the slope coefficient, which is greater than one and increasing with the interval, accounts for much of the increment to the returns‐earnings R². In fact, constraining the slope coefficient to be one results in an R² of 11 percent for the 10‐year interval, which is considerably lower than the R² of 47 percent when the regression is unconstrained. Hence, the positive covariance between current earnings and the accounting lag, rather than the diminishing effect of the accounting lag, appears to be the dominant explanation for the observed high R² over long intervals.     

Wage returns to education in Ethiopia

ABSTRACT

In this paper, we aim to provide robust estimates of wage returns to education in Ethiopia. Previous estimates vary widely based on the scope and size of the study sample, variables employed, and estimation method. We use two recent rounds of national labour force survey data and a pseudo- (or synthetic) panel framework to address the well-known potential endogeneity of schooling in wage regressions. Birth-year cohort based pseudo-panel estimate of the return to an additional year of education is between 14 percent and 16 percent, 4 to 5 percentage points higher than that from ordinary least squares (OLS). The significant downward bias in OLS is further confirmed by two-year pseudo-panel estimates and remains robust, to a large extent, as we use an alternate model, change the estimation sample, and address selection bias concurrently with endogenous schooling using a novel approach. We discuss some possible explanations in the context of Ethiopia.     

On the estimation of returns to scale, technical progress and monopolistic markups

A number of theoretical results on estimating returns to scale, technical progress and monopolistic markups are derived when there are multiple outputs and inputs. The choice of value added versus gross output and problems that arise in aggregation across sectors of an economy are also considered. Using US data on manufacturing, evidence is found of increasing returns to scale across all levels of aggregation. Technical progress is typically found to be insignificant implying that economic growth has been driven by increasing returns to scale rather than technical progress. Such findings have important implications for the macroeconomic modeling of economic fluctuations.     

上市公司综合盈利水平与股票收益

本文基于2000-2017年上市公司的财务及股票交易数据,研究了上市公司综合盈利水平与股票收益之间的关系。我们使用目前资产定价文献中较新的偏最小二乘法和组合预测法,从12个衡量公司盈利能力的指标中提取了一个测度上市公司综合盈利水平的指标。研究结果显示,上市公司综合盈利水平能够显著预测未来股票收益。使用单因子偏最小二乘法、取12个月斜率的平均值构造的综合盈利水平最有效,以其构建的多空对冲投资组合能产生15%的年平均收益,夏普比率达到0.75。与此对应,组合预测法提取的上市公司综合盈利水平的预测能力稍低,但依然显著。在控制了其他公司特征变量后,综合盈利水平对于股票收益的解释能力依然稳健。本文还从经济机制的角度出发,探讨了综合盈利水平对收益的预测来源。我们发现,上市公司综合盈利水平与股票预期回报的正向关系在投资摩擦更低的组中更高,而在错误定价程度更高的组通常更低。这些结果支持了基于投资摩擦的Q理论,而与行为金融的错误定价理论相悖。     

The educational and labor market returns to preschool attendance in Austria

Preschool attendance is widely recognized as a key ingredient for later socioeconomic success, mothers’ labor market participation, and leveling the playing field for children from disadvantaged backgrounds. However, the empirical evidence for these claims is still relatively scarce, particularly in Europe. Using data from the 2011 Austrian European Union Statistics of Income and Living Conditions (EU-SILC), we contribute to this literature by studying the effects of having attended preschool for the adult Austrian population. We find strong and positive effects of preschool attendance on later educational attainment, the probability of working full time, hourly wages, and the probability that the mother is in the labor market. Full time workers at the bottom and the top of the distribution benefit less than those in the middle. Women in particular benefit more in terms of years of schooling and the probability of working full time. Other disadvantaged groups (second generation migrants; people with less educated parents) also often benefit more in terms of education and work.     

R&D投入与公司价值相关性的实证分析——以我国生物制药和电子信息技术行业上市公司为例

以2007—2009年我国生物制药和电子信息技术行业上市公司为研究样本,实证考察R&D投入与公司价值的相关性。首先检验R&D投入对公司经营业绩的作用,然后运用改进的Fama-French三因子模型,检验R&D投入的市场估值效应。结果显示,R&D投入与公司本年主营业务利润正相关,与同期股价和未来一年的股价变动正相关,但不显著。说明生物制药和电子信息技术企业研发投入的价值,在新会计准则实施和股权分置改革完成后,仍未得到市场的有效认可。     

Measuring heterogeneity in the returns to education using an education reform

In this paper, we explore the impact of a mandatory education reform as well as pre-reform availability of schools above the mandatory level, on educational attainment and returns to education in Norway. We contribute to the existing literature by focusing on the heterogeneity of the impact of reforms. Our results indicate that increased compulsory education from seven to nine years increased the general level of education beyond the compulsory education. We also find that the effect of family background on educational attainment was weaker after the reform. The average treatment effect on returns to education is surprisingly high for education of intermediate duration. This means that increasing the general level of education potentially generates high returns in the form of wages. We also find that the effect of treatment on the treated on the returns to education is 1-4 percentage points higher than the average treatment effect.     

Small firms and the value of improvements in corporate governance mechanisms

Since 2002, many firms have been required to alter their board of directors and committees to increase management monitoring. Kinney and McDaniel (1989) and Chhaochharia and Grinstein (2007) provide empirical evidence suggesting that investments in corporate governance may differ based on firm size, and that under-investing in monitoring may be more pronounced in smaller firms. To further test whether the benefits of recent changes in companies' governance mechanisms accrue to smaller firms that have underinvested in governance, we examine the stock market reaction to changes in board structure over the twenty-four months following the passage of the Sarbanes–Oxley Act. We construct a new composite measure of board structure and regress buy-and-hold abnormal returns on changes that occur in the Board Structure Index, finding that improvements in corporate governance quality result in economically significant abnormal returns accruing only to the smaller firms with weak initial board structures.