18,040 research outputs found
Physicists, stamp collectors, human mobility forecasters
One of the two reviewers studied in high school to be a physicist. In the end, he became something else, but he never lost his awe of physics. The other reviewer never intended to become a physicist, but he sometimes asks himself why he didn’t become one. Today, they are both sociologists who practice their science on an action theory basis and believe that regularities exist in the
world of social actions which can be perceived, understood, explained – and even used for making predictions
A Brief Study of Open Source Graph Databases
With the proliferation of large irregular sparse relational datasets, new
storage and analysis platforms have arisen to fill gaps in performance and
capability left by conventional approaches built on traditional database
technologies and query languages. Many of these platforms apply graph
structures and analysis techniques to enable users to ingest, update, query and
compute on the topological structure of these relationships represented as
set(s) of edges between set(s) of vertices. To store and process Facebook-scale
datasets, they must be able to support data sources with billions of edges,
update rates of millions of updates per second, and complex analysis kernels.
These platforms must provide intuitive interfaces that enable graph experts and
novice programmers to write implementations of common graph algorithms. In this
paper, we explore a variety of graph analysis and storage platforms. We compare
their capabil- ities, interfaces, and performance by implementing and computing
a set of real-world graph algorithms on synthetic graphs with up to 256 million
edges. In the spirit of full disclosure, several authors are affiliated with
the development of STINGER.Comment: WSSSPE13, 4 Pages, 18 Pages with Appendix, 25 figure
Millions to the Polls: Practical Policies to Fulfill the Freedom to Vote for All Americans
Voting is the bedrock of America's democracy. In a government of, by, and for the people, casting a ballot is the fundamental means through which we all have a say in the political decisions that affect our lives. Yet now, without substantial interventions, the freedom to vote is at great risk.This report contains a comprehensive and bold agenda of 16 policy proposals and common sense reforms. It details policies to help us realize the full promise of a democracy
Syngenta -- The Genome Giant?
Swiss gene giant Syngenta, the world's largest agrochemical corporation and third largest seed company (see tables) has applied for patents that could effectively allow the company to monopolize key gene sequences that are vital for rice breeding as well as dozens of other plant species. While the Genome Giant "donates" rice germplasm and information to public researchers with one hand, it is attempting to monopolize rice resources with the other. Governments, public sector researchers and the United Nations must re-evaluate and reform their cozy connections to companies like Syngenta
Fast Exact Search in Hamming Space with Multi-Index Hashing
There is growing interest in representing image data and feature descriptors
using compact binary codes for fast near neighbor search. Although binary codes
are motivated by their use as direct indices (addresses) into a hash table,
codes longer than 32 bits are not being used as such, as it was thought to be
ineffective. We introduce a rigorous way to build multiple hash tables on
binary code substrings that enables exact k-nearest neighbor search in Hamming
space. The approach is storage efficient and straightforward to implement.
Theoretical analysis shows that the algorithm exhibits sub-linear run-time
behavior for uniformly distributed codes. Empirical results show dramatic
speedups over a linear scan baseline for datasets of up to one billion codes of
64, 128, or 256 bits
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