The flood algorithm—a multivariate, self-organizing-map-based, robust location and covariance estimator

Self-organizing maps (SOMs) introduced by Kohonen (Biol. Cybern. 43(1):59–69, 1982) are well-known in the field of artificial neural networks. The way SOMs are performing is very intuitive, leading to great popularity and numerous applications (related to statistics: classification, clustering). The result of the unsupervised learning process performed by SOMs is a non-linear, low-dimensional projection of the high-dimensional input data, that preserves certain features of the underlying data, e.g. the topology and probability distribution (Lee and Verleysen in Nonlinear Dimensionality Reduction, Springer, 2007; Kohonen in Self-organizing Maps, 3rd edn., Springer, 2001).     

Social Participation, Sense of Community and Social Well Being: A Study on American, Italian and Iranian University Students

Aim of the study was to assess the relationship between social participation and Sense of Community in a sample of University students and the impact of such variables on Social well being. A further aim was to assess the generality of the relationships between these constructs across different countries, and specifically, the USA, Italy and Iran. The sample includes 200 Italian, 125 American and 214 Iranian University students, male and female. Results show higher levels of social participation, Sense of Community and Social well being among American students. Sense of Community is positively correlated with social participation in all three samples; however, only among Italian students social participation positively predicts Social well being. Implications of results will be discussed.     

中日关系的症结与处方

中国实行改革开放以后,邓小平等中国领导人非常重视中国与欧美日的关系。1978年邓小平访问日本,增加了对日本的了解。他有很多日本朋友,其中不仅有自民党、公明党的议员,许多地方官员、记者、企业家都是他的好朋友。他利用会见大量日本客人的机会,掌握了更多的日本的情况,并且收到很多日本高级专家提出的建议。邓小平是一位伟大的     

AIRLINE PRICING BEHAVIOR UNDER LIMITED INTER‐MODAL COMPETITION

This paper empirically analyzes airline pricing for short‐haul flights in contexts with no credible threat of inter‐modal competition. To this end, we explore the southern Italian market since it is less accessible by other transport modes and thus fares are the direct outcome of air‐related competition. We show, in fact, that market power matters, depending on the level of intra‐modal competition, and that airlines apply differentiated mark‐ups. Besides, consistent with the implementation of inter‐temporal price discrimination (IPD), we find a non‐monotonic inter‐temporal profile of fares with a turning point included in the interval of the 43rd to 45th days before departure. Finally, we provide evidence that in more competitive markets, airlines are more likely to engage in IPD. (JEL L11, L13, L93)     

A Turning Point in Gender Bias in Mortality? An Update on the Number of Missing Women

Amartya Sen started a debate about gender bias in mortality by estimating the number of “missing women,” which refers to the number of females of any age who have presumably died as a result of discriminatory treatment. Depending on the assumptions made, the combined estimates for countries exhibiting the presence of such gender bias varied between 60 and 107 million. As new population data have become available for these countries, this article examines whether the number of “missing women” has changed in the past decade. The combined estimate of the number of missing women has risen in absolute terms but has fallen slightly in relation to overall population. Considerable improvement is evident in West Asia, North Africa, and parts of South Asia, while only small improvements have occurred in India and a deterioration took place in China. Analyses of the underlying causes of gender bias in mortality suggest that improvements are largely related to improved female education and employment opportunities and rising overall incomes, while deterioration is mostly attributable to the rising incidence of sex‐selective abortions.