Can Restitution Save Fragile Spiderless Networks?

This Article examines the dramatic increase in business networks in recent decades and considers whether the law can play a useful role in supporting the efficient functioning of these inter-firm relationships for coordination and cooperation. Repeat play, reputational sanctions, and norms of trust and reciprocity are the common explanations for the flourishing of networks in many industries and places. But the evidence also shows that a certain class of networks often fails to survive or function effectively and beneficial cooperation among these network members is impaired. These fragile networks develop organically without a controlling party or hierarchy at the center of the network to facilitate network formation. Lacking a controlling entity, they are webs without any spider. Clusters of industrial districts are traditional examples of this class of networks. More recently, the information revolution has stimulated a dramatic increase in another type of spiderless network: networks of strategic alliances are now a common means of organizing collaborations among firms in high technology and R&D intensive settings. In both types of spiderless networks there are no legal mechanisms to control moral hazard and free riding risks during the period of network formation and operation. We show how in theory the law could support spiderless networks by allowing firms who externalize benefits to other firms in the network to recover for those benefits. Practical considerations may limit the implementation of a full-blown right of restitution. Nevertheless, by recognizing a limited right to recover for uncompensated costs and benefits in appropriate cases, the law can function as a background norm for sharing costs and benefits among network members, motivating them to overcome daunting coordination problems. We consider several implementation issues, show how they might be resolved, and apply our analysis to a set of well-known spiderless networks

Telework Configurations and Labour Productivity: some stylized facts

The development of information and communication technologies has led to the rise of new working forms in firms, some of which are temporally and spatially dispersed, such as telework practices. However, ‘telework’ is a broad concept, including different forms of remote work as well as diverse reasons and performance implications for the separation of work from the firm’s premises. Following this consideration, this paper has explored two sides of telework: 1) the main types of telework practises adopted by firms in relation to their technological, organizational and environmental context; 2) the association between the adoption of telework practices and labour productivity. Specifically, analysing data gathered through a survey analysis conducted from 2005 and 2009 on Italian enterprises, we identified two main typologies of telework: 1) firms using forms of home‐based telework; 2) firms using mobile forms of telework. Whereas firms prevalently using the first type of telework modality do not exhibit a superior endowment of information systems and do not exhibit higher labour productivity, firms deploying “mobile work” practices are characterized by a higher adoption of information systems, deal with more dynamic business environments and exhibit higher labour productivity with respect to firms that do not use telework practices

Distance Oracles for Time-Dependent Networks

We present the first approximate distance oracle for sparse directed networks with time-dependent arc-travel-times determined by continuous, piecewise linear, positive functions possessing the FIFO property. Our approach precomputes $(1+\epsilon)-$approximate distance summaries from selected landmark vertices to all other vertices in the network. Our oracle uses subquadratic space and time preprocessing, and provides two sublinear-time query algorithms that deliver constant and $(1+\sigma)-$approximate shortest-travel-times, respectively, for arbitrary origin-destination pairs in the network, for any constant $\sigma > \epsilon$. Our oracle is based only on the sparsity of the network, along with two quite natural assumptions about travel-time functions which allow the smooth transition towards asymmetric and time-dependent distance metrics.Comment: A preliminary version appeared as Technical Report ECOMPASS-TR-025 of EU funded research project eCOMPASS (http://www.ecompass-project.eu/). An extended abstract also appeared in the 41st International Colloquium on Automata, Languages, and Programming (ICALP 2014, track-A

Using cascading Bloom filters to improve the memory usage for de Brujin graphs

De Brujin graphs are widely used in bioinformatics for processing next-generation sequencing data. Due to a very large size of NGS datasets, it is essential to represent de Bruijn graphs compactly, and several approaches to this problem have been proposed recently. In this work, we show how to reduce the memory required by the algorithm of [3] that represents de Brujin graphs using Bloom filters. Our method requires 30% to 40% less memory with respect to the method of [3], with insignificant impact to construction time. At the same time, our experiments showed a better query time compared to [3]. This is, to our knowledge, the best practical representation for de Bruijn graphs.Comment: 12 pages, submitte

For-all Sparse Recovery in Near-optimal Time

An approximate sparse recovery system in $\ell_1$ norm consists of parameters $k$, $\epsilon$, $N$, an $m$-by-$N$ measurement $\Phi$, and a recovery algorithm, $\mathcal{R}$. Given a vector, $\mathbf{x}$, the system approximates $x$ by $\widehat{\mathbf{x}} = \mathcal{R}(\Phi\mathbf{x})$, which must satisfy $\|\widehat{\mathbf{x}}-\mathbf{x}\|_1 \leq (1+\epsilon)\|\mathbf{x}-\mathbf{x}_k\|_1$. We consider the 'for all' model, in which a single matrix $\Phi$, possibly 'constructed' non-explicitly using the probabilistic method, is used for all signals $\mathbf{x}$. The best existing sublinear algorithm by Porat and Strauss (SODA'12) uses $O(\epsilon^{-3} k\log(N/k))$ measurements and runs in time $O(k^{1-\alpha}N^\alpha)$ for any constant $\alpha > 0$. In this paper, we improve the number of measurements to $O(\epsilon^{-2} k \log(N/k))$, matching the best existing upper bound (attained by super-linear algorithms), and the runtime to $O(k^{1+\beta}\textrm{poly}(\log N,1/\epsilon))$, with a modest restriction that $\epsilon \leq (\log k/\log N)^{\gamma}$, for any constants $\beta,\gamma > 0$. When $k\leq \log^c N$ for some $c>0$, the runtime is reduced to $O(k\textrm{poly}(N,1/\epsilon))$. With no restrictions on $\epsilon$, we have an approximation recovery system with $m = O(k/\epsilon \log(N/k)((\log N/\log k)^\gamma + 1/\epsilon))$ measurements

The first Neanderthal remains from an open-air Middle Palaeolithic site in the Levant

The late Middle Palaeolithic (MP) settlement patterns in the Levant included the repeated use of caves and open landscape sites. The fossil record shows that two types of hominins occupied the region during this period - Neandertals and Homo sapiens. Until recently, diagnostic fossil remains were found only at cave sites. Because the two populations in this region left similar material cultural remains, it was impossible to attribute any open-air site to either species. In this study, we present newly discovered fossil remains from intact archaeological layers of the open-air site 'Ein Qashish, in northern Israel. The hominin remains represent three individuals: EQH1, a nondiagnostic skull fragment; EQH2, an upper right third molar (RM3); and EQH3, lower limb bones of a young Neandertal male. EQH2 and EQH3 constitute the first diagnostic anatomical remains of Neandertals at an open-air site in the Levant. The optically stimulated luminescence ages suggest that Neandertals repeatedly visited 'Ein Qashish between 70 and 60 ka. The discovery of Neandertals at open-air sites during the late MP reinforces the view that Neandertals were a resilient population in the Levant shortly before Upper Palaeolithic Homo sapiens populated the region