Robohub.org
 

When you can’t collect all the data you need, a new algorithm tells you which to target | MIT News

by
01 August 2014



share this:

Levine and How developed an algorithm that can efficiently calculate just how much information any node in the graph gives you about any other — what in information theory is called “mutual information.” As Levine explains, one of the obstacles to performing that calculation efficiently is the presence of “loops” in the graph, or nodes that are connected by more than one path.

Calculating mutual information between nodes, Levine says, is kind of like injecting blue dye into one of them and then measuring the concentration of blue at the other. “It’s typically going to fall off as we go further out in the graph,” Levine says. “If there’s a unique path between them, then we can compute it pretty easily, because we know what path the blue dye will take. But if there are loops in the graph, then it’s harder for us to compute how blue other nodes are because there are many different paths.”

So the first step in the researchers’ technique is to calculate “spanning trees” for the graph. A tree is just a graph with no loops: In a family tree, for instance, a loop might mean that someone was both parent and sibling to the same person. A spanning tree is a tree that touches all of a graph’s nodes but dispenses with the edges that create loops.

Read more by Larry Hardesty at MIT News

 



tags: , ,


Hallie Siegel robotics editor-at-large
Hallie Siegel robotics editor-at-large





Related posts :



Robot science fiction books of 2021

2021 produced four new scifi books with good hard science underpinning their description of robots and three where there was less science but lots of interesting ideas about robots.
23 January 2022, by

How robots learn to hike

A new control approach that enables a legged robot, called ANYmal, to move quickly and robustly over difficult terrain.
20 January 2022, by

How robots and bubbles could soon help clean up underwater litter

Everyone loves to visit the seaside, whether to enjoy the physical benefits of an exhilarating swim or simply to relax on the beach and catch some sun. But these simple life affirming pleasures are easily ruined by the presence of litter, which if persistent can have a serious negative impact on both the local environment and economy. However, help is at hand to ensure the pristine nature of our coastlines.
19 January 2022, by

Maria Gini wins the 2022 ACM/SIGAI Autonomous Agents Research Award

Congratulations to Maria Gini on winning this prestigious award, recognising her research and leadership in the field of robotics and multi-agent systems.
18 January 2022, by

UN fails to agree on ‘killer robot’ ban as nations pour billions into autonomous weapons research

Given the pace of research and development in autonomous weapons, the U.N. meeting might have been the last chance to head off an arms race.
16 January 2022, by

Science Magazine robot videos 2021

A compilation of Science Magazine videos featuring robotics research that were released during last year.
14 January 2022, by





©2021 - ROBOTS Association


 












©2021 - ROBOTS Association