Network analysis has attracted significant attention when researching the phenomenon of transnational terrorism, particularly Al Qaeda. While many scholars have made valuable contributions to mapping Al Qaeda, several problems remain due to a lack of data and the omission of data provided by international organizations such as the UN. Thus, this article applies a social network analysis and subsequent mappings of the data gleaned from the Security Council's consolidated sanctions list, and asks what they can demonstrate about the structure and organizational characteristics of Al Qaeda. The study maps the Al Qaeda network on a large scale using a newly compiled data set. The analysis reveals that the Al Qaeda network consists of several hundred individual and group nodes connecting almost all over the globe. Several major nodes are crucial for the network structure, while simultaneously many other nodes only weakly and foremost regionally connect to the network. The article concludes that the findings tie in well to the latest research pointing to local and simultaneously global elements of Al Qaeda, and that the new data is a valuable source for further analyses, potentially in combination with other data.
Employing the data from the Survey of Health, Ageing and Retirement in Europe (SHARE) for 13 European countries, we analyse the relationship between mother's age at first birth and her health at age 45 to 56. Compared to mothers who gave birth at middle age, we found a significantly higher risk of illness among young first-time mothers. In a first step, we show that this effect largely remains after controlling for selection effects which determine age at first birth. Next, we examine whether the biosocial view could be confirmed. This approach explains the negative effect of early births on later health through a lack of social and economic resources during young mothers' life course. Thus, fewer resources are expected to affect health outcomes. However, the results indicate that the negative effect of young age at first birth remains even after controlling for health-related resources throughout the life course. The operationalisation of health-related resources as well as unobserved effects might be regarded as possible explanations for this. Due to data restrictions, indicators for educational history, job history and social support, that are all likely to depend on age at first birth and also affect later health, could not be taken into account. The results identify mechanisms of cumulative social inequality when disadvantaged women become mothers at younger age and thereby further increase their risk of disease.
The crowdfunding phenomenon has garnered a considerable amount of attention in recent years. Several online crowdfunding platforms have risen to prominence; they can be characterized as two-sided marketplaces. Recent research reveals initial insights into the dynamics and characteristics of crowdfunding networks arising from such marketplaces. This research, though, is restricted primarily to analyses of static network snapshots and at the dyadic level. In this study, we use a large longitudinal dataset to analyze the behavior of actors on both sides of the market who promote their own and fund others’ projects. We investigate the influence of endogenous and exogenous effects on the dynamics of crowdfunding networks. Our results provide evidence for mechanisms promoting a hierarchical network organization and the absence of homophily-related mechanisms regarding gender or geographic distance. Moreover, we establish that experienced and popular project creators fund fewer projects.
Organizations increasingly rely on group-based organizational structures to manage uncertain environments. However, at the group level there is still a limited understanding of how boundary-spanning activities should be managed to increase group performance. In this paper, we propose "out-group-tie centralization" as a concept that refers to the variation in the group members' network ties to other social actors who are not members of the group itself. When the out-group-tie centralization is low, no group member enjoys substantially more ties to other social actors outside the group than does any other group member. A panel analysis with 120 work groups from a medium-size German bank over a 12-month period reveals a reversed u-shaped relationship between out-group-tie centralization and group performance. However, the results indicate no association between the density of a work group communication network and that group's performance.
Social media are a primary means for travelers to connect with each other and plan trips. They can also help tourism suppliers (e.g., by providing relevant information), thus overcoming the shortcomings of traditional information sources. User-generated content from social media has already been used in many studies as a primary information source. However, the quality of information derived thus far remains largely unclear. This study assesses the quality of macro-level information on the spatio-temporal distribution of tourism derived from online travel reviews in social media in terms of completeness, timeliness, and accuracy. We found that information quality increased from 2000 to 2009 as online travel reviews increasingly covered more countries, became available earlier than statistics reported by the United Nations World Tourism Organization (UNWTO), were highly correlated with the UNWTO statistics. We conclude that social media are a good information source for macro-level spatio-temporal tourism information and could be used, for example, to estimate tourism figures.
This paper examines cross-cultural gender differences in the adoption and usage of the social media platform Last.FM. From a large-scale empirical study of 3748 Last.FM users from Australia, Finland, Germany, and the United States of America, we find: (1) men listen to more pieces of music on social media platforms than do women; (2) women focus their listening on fewer musical genres and fewer tracks than do men; (3) women register on Last.FM later than do “early adopting” men (absolutely and in comparison to their friends), but at a younger age; (4) women maintain more virtual friendships on Last.FM than do men; and (5) women, when choosing music to listen to on social media platforms, are more likely than are men to choose tracks that correspond to mainstream tastes.
In this volume, we are publishing three centuries of Cyrillic and Glagolitic alphabet tables from Western sources. The illustrations presented here have been enhanced, cleaned up and digitally restored. Most of them have never been published in such a high quality before.
The beginnings of the continuous human presence and of pastoral activities in the high mountainous region of Central Europe have recently become a frequently discussed topic in both archaeology and palaeoecology. In extreme environments such as the high Alpine main ridge and adjacent areas, highly adaptive subsistence strategies were required to exploit natural resources available in the subalpine and alpine zones. Such strategies were determined by changing environmental, social, and economic conditions.
To investigate the relationships between settlement dynamics, human impact, and Holocene climatic changes, we studied the valleys of the Silvretta Massif in the central Eastern Alps between the Paznaun (Austria) and Lower Engadine valleys (Switzerland). We are presenting new archaeological, palaeoecological, and pedological evidence of continuous human activities from the Early Neolithic Period to the Bronze Age (~ 5,500–800 BC). This evidence sheds new light on the beginnings of intensifi ed human impact on the high mountainous landscape, i.e. activities beyond Mesolithic hunting along the timberline. Archaeological data suggest a shift in subsistence strategies from hunting to herding at the end of the Neolithic Period (~2,800–2,500 BC). While palaeoecological data confirm this trend, they also indicate potentially earlier human and livestock impact through forest clearances by fire and grazing from about 4,200 BC onwards. In addition to archaeological sites and peat bogs, soils in high-altitude regions prove to be appropriate archives indicating former vegetation cover, shifts of timberline altitudes as well as disturbance of soil formation by human activity such as by slash-and-burn and by livestock grazing.