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Prediction or cause Information theory may hold the key

Prediction or cause Information theory may hold the key

first_img More information: Daniel W. Hahs and Shawn D. Pethel, “Distinguishing Anticipation from Causality: Anticipatory Bias in the Estimation of Information Flow,” Physical Review Letters (2011). Available online: link.aps.org/doi/10.1103/PhysRevLett.107.128701 Citation: Prediction or cause? Information theory may hold the key (2011, September 30) retrieved 18 August 2019 from https://phys.org/news/2011-09-theory-key.html Pethel is a scientist working at the Redstone Arsenal in Alabama. Along with Daniel Hahs, he set out to identify a method of distinguishing anticipation from causality using tools from information theory. “Any process that has to react in real time can improve its performance through anticipation, and in studying such processes it is important to find new ways to quantify causality” Pethel says. The question of anticipation versus causality is one that has real-world application in a number of areas. Pethel points out that this issue has implications in covert operations, as well as in financial areas, especially with regard to the development of bubbles. “Is there a way, from passive measurements, to tell what’s driving what?” Pethel and Hahs try to answer this question in Physical Review Letters: “Distinguishing Anticipation from Causality: Anticipatory Bias in the Estimation of Information Flow.”“If a system is generating information, it’s like a fingerprint that can be used to figure out where the information is coming from and where it is going,” Pethel explains. “A quantity called transfer entropy has been used since 1990 to measure information flow in experimental data from neuroscience, finance and even music.”“What we were interested in,” he continues, “is the anticipation issue. We wanted to look at that using transfer entropy, and see if we could discover what’s predicting and what’s causing.”In order to set up the situation, Pethel and Hahs used chaotic systems, which produce information. They were careful that their model would be connected in only one direction. “We set it up so that we know the causality – that x is causing y, but y cannot cause anything for x. However, we designed the y system to be able to predict x to some degree. We then collected data and used transfer entropy to tell us which was the causal system.”When analyzing the results, Pethel and Hahs found something rather interesting: Even though the response system, y, wasn’t the cause, it looked very much like it was under many different test conditions. “There is an anticipatory bias. It’s a very strong effect, the more anticipation there is, the stronger it will be. There is a huge bias going on in some cases, and it is giving the exact wrong answer. The system that was only predictive was indistinguishable from the cause.”The good news is that Pethel and Hahs also noticed that there are some signs that indicate that the presence of a bias. “Even if you can’t pinpoint what the causal source is, you can see some behaviors that provide clues that you need to be on the alert for anticipatory dynamics.”Pethel wants to take this further, though. “We’ve studied the one way system, and now that we know there is a bias, we can account for that, and study systems that have mutual back and forth coupling.”Hopefully, the work will provide helpful clues in understanding how causality can be indentified using information theory. “There’s a level of broad interest,” Pethel says, “since you can deduce causal mechanisms from data. Particularly interesting are financial markets and biological systems where anticipation plays a large role in allowing systems to adapt to a changing environment.” Don’t have all the information? In the quantum world, that doesn’t matter Copyright 2011 PhysOrg.com. All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of PhysOrg.com.center_img (PhysOrg.com) — “A perplexing philosophical issue in science is the question of anticipation, or prediction, versus causality,” Shawn Pethel tells PhysOrg.com. “Can you tell the difference between something predicting an event and something actually causing an event?” This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Explore furtherlast_img read more

Missing presiding officer found murdered in Raiganj

Missing presiding officer found murdered in Raiganj

first_imgBalurghat: A presiding officer who had gone missing since May 14, was found murdered on Tuesday evening.The corpse of the presiding officer, Rajkumar Roy, was discovered by the local people beside a railway track from Sonadangi area under Raiganj police station in North Dinajpur district.The State Election Commission has sought a report from the District Magistrate of North Dinajpur. The District Magistrate has order a probe by the Criminal Investigation Department (CID). Also Read – Heavy rain hits traffic, flightsRoy, who had been working as an assistant teacher of English in Rahatpur High Madrasha of Karandighi, was deployed as presiding officer at booth no. 48 in Itahar block. On Monday at around 8 pm, he left for toilet from the booth but never returned. His mobile phone was switched off.Worried family members contacted the officials of Itahar block to know his whereabouts. A missing complaint was also lodged at the police station by the concerned BDO.On Tuesday, some local people found a body with multiple stab injuries beside a railway track and informed police. Police went to the spot and suspected the body to be Roy. His family members were also intimated. Later, the deceased’s brother identified him. Also Read – Speeding Jaguar crashes into Merc, 2 B’deshi bystanders killedPolice investigation has been initiated in this regard. Preliminary investigation has revealed that Roy was stabbed brutally to death by his assailants. Police said the body was lying in pool of blood. They have sent the body for post-mortem.On Wednesday, the polling personnel staged a demonstration at Ghorimore in Raiganj, demanding arrest of the culprits involved with the crime. The irate polling personnel demanded safety measures from the administration. Sub-divisional district magistrate of Raiganj T N Sherpa, who rushed to the spot to pacify the agitators, was gheraoed and allegedly thrashed by them. Later, a large contingent of police and RAF from Raiganj police station rescued Sherpa and lifted the demonstration.Police superintendent Shyam Singh said the assailants will be arrested soon.last_img read more