42,874 research outputs found
A Formal Treatment of Generalized Preferential Attachment and its Empirical Validation
Generalized preferential attachment is defined as the tendency of a vertex to
acquire new links in the future with respect to a particular vertex property.
Understanding which properties influence link acquisition tendency (LAT) gives
us a predictive power to estimate the future growth of network and insight
about the actual dynamics governing the complex networks. In this study, we
explore the effect of age and degree on LAT by analyzing data collected from a
new complex-network growth dataset. We found that LAT and degree of a vertex
are linearly correlated in accordance with previous studies. Interestingly, the
relation between LAT and age of a vertex is found to be in conflict with the
known models of network growth. We identified three different periods in the
network's lifetime where the relation between age and LAT is strongly positive,
almost stationary and negative correspondingly
Structural Deep Embedding for Hyper-Networks
Network embedding has recently attracted lots of attentions in data mining.
Existing network embedding methods mainly focus on networks with pairwise
relationships. In real world, however, the relationships among data points
could go beyond pairwise, i.e., three or more objects are involved in each
relationship represented by a hyperedge, thus forming hyper-networks. These
hyper-networks pose great challenges to existing network embedding methods when
the hyperedges are indecomposable, that is to say, any subset of nodes in a
hyperedge cannot form another hyperedge. These indecomposable hyperedges are
especially common in heterogeneous networks. In this paper, we propose a novel
Deep Hyper-Network Embedding (DHNE) model to embed hyper-networks with
indecomposable hyperedges. More specifically, we theoretically prove that any
linear similarity metric in embedding space commonly used in existing methods
cannot maintain the indecomposibility property in hyper-networks, and thus
propose a new deep model to realize a non-linear tuplewise similarity function
while preserving both local and global proximities in the formed embedding
space. We conduct extensive experiments on four different types of
hyper-networks, including a GPS network, an online social network, a drug
network and a semantic network. The empirical results demonstrate that our
method can significantly and consistently outperform the state-of-the-art
algorithms.Comment: Accepted by AAAI 1
The Formation of Risk Sharing Networks.
This paper examines the formation of risk sharing networks in the rural Philippines. We find that geographic proximity–possibly correlated with kinship–is a major determinant of mutual insurance links among villagers. Age and wealth differences also play an important role. In contrast, income correlation and differences in occupation are not determinants of network links. Reported network links have a strong effect on subsequent gifts and loans. Gifts between network partners are found to respond to shocks and to differences in health status. From this we conclude that intra-village mutual insurance links are largely determined by social and geographical proximity and are only weakly the result of purposeful diversification of income risk. The paper also makes a methodological contribution to the estimation of dyadic models.partage du risque; modèle dyadique; dyadic model; Philippines; Network; risk-sharing; Réseau;
- …