Today’s information retrieval applications have become increasingly complex. The Social Book Search (SBS) lab at CLEF 2015 allows evaluating retrieval methods on a complex search task with several textual and non-textual meta-data fields. The challenge is to incorporate the different information types (modalities) into a single ranked list. We build a strong textual baseline and combine it with...

The privacy concerns associated with data analysis over social networks have spurred recent research on privacypreserving social network analysis, particularly on privacypreserving publishing of social network data. In this paper, we focus on whether we can reconstruct a graph from the edge randomized graph such that accurate feature values can be recovered. In particular, we present a low rank...

Many accounts of social influences on exercise participation describe how people compare their behaviors to those of others. We develop and test a novel hypothesis, the exercise rank hypothesis, of how this comparison can occur. The exercise rank hypothesis, derived from evolutionary theory and the decision by sampling model of judgment, suggests that individuals' perceptions of the health bene...

Uncovering unknown or missing links in social networks is a difficult task because of their sparsity, and because links may represent different types of relationships, characterized by different structural patterns. In this paper, we define a simple yet efficient supervised learning-to-rank framework, called RankMerging, which aims at combining information provided by various unsupervised ranki...

Our formal understanding of the inductive bias that drives the success of convolutional networks on computer vision tasks is limited. In particular, it is unclear what makes hypotheses spaces born from convolution and pooling operations so suitable for natural images. In this paper we study the ability of convolutional networks to model correlations among regions of their input. We theoreticall...

This paper describes a theory of rational emulation and deviance. It assumes that individuals care about relative position (or ‘status’), and constructs a model of decisionmaking in social and economic settings. The analysis shows why individuals who want to be different from others will, paradoxically, find it rational to imitate other people. The paper also provides a choice-theoretic foundat...

We have collected and cleaned two network data sets: Coauthorship and Citation networks for statisticians. The data sets are based on all research papers published in four of the top journals in statistics from 2003 to the first half of 2012. We analyze the data sets from many different perspectives, focusing on (a) productivity, patterns and trends, (b) centrality, and (c) community structures...

Let γ(G) and ir(G) denote the domination number and the irredundance number of a graph G, respectively. Allan and Laskar [1] and Bollobás and Cockayne [2] proved independently that γ(G) < 2 ir(G) for any graph G. For a tree T , Damaschke [4] obtained the sharper estimation 2γ(T ) < 3 ir(T ). Extending Damaschke’s result, Volkmann [11] proved that 2γ(G) ≤ 3 ir(G) for any block graph G and for an...

The environmental impact of IT is facing increasing public attention. The search engine Ecosia takes advantage of this situation by pursuing a Social Business model. Search engines need electricity to provide their services and indirectly produce CO2. The estimation of greenhouse gas emissions for the average search query using the market leader Google fluctuate between 0.2 g and 10.0 g of CO2....