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Comment by Panorama on Open Thread, Aug. 8 - Aug 14. 2016 · 2016-08-14T10:35:18.285Z · LW · GW

Researchers orbit a muon around an atom, confirm physics is broken

The proton's charge radius shouldn't change, and yet it appears to.

Comment by Panorama on Open Thread, Aug. 1 - Aug 7. 2016 · 2016-08-03T10:37:36.048Z · LW · GW

Medical benefits of dental floss unproven

The federal government has recommended flossing since 1979, first in a surgeon general's report and later in the Dietary Guidelines for Americans issued every five years. The guidelines must be based on scientific evidence, under the law.

Last year, the Associated Press asked the departments of Health and Human Services and Agriculture for their evidence, and followed up with written requests under the Freedom of Information Act.

When the federal government issued its latest dietary guidelines this year, the flossing recommendation had been removed, without notice. In a letter to the AP, the government acknowledged the effectiveness of flossing had never been researched, as required.

The AP looked at the most rigorous research conducted over the past decade, focusing on 25 studies that generally compared the use of a toothbrush with the combination of toothbrushes and floss. The findings? The evidence for flossing is "weak, very unreliable," of "very low" quality, and carries "a moderate to large potential for bias."

Comment by Panorama on Open thread, Jun. 13 - Jun. 19, 2016 · 2016-06-13T16:45:27.338Z · LW · GW

1,500 scientists lift the lid on reproducibility

Survey sheds light on the ‘crisis’ rocking research.

Full questionnaire

Raw data

Comment by Panorama on Open thread, Jun. 13 - Jun. 19, 2016 · 2016-06-13T16:23:29.123Z · LW · GW

University Innovation and the Professor's Privilege by Hans K. Hvide, Benjamin F. Jones

National policies take varied approaches to encouraging university-based innovation. This paper studies a natural experiment: the end of the “professor’s privilege” in Norway, where university researchers previously enjoyed full rights to their innovations. Upon the reform, Norway moved toward the typical U.S. model, where the university holds majority rights. Using comprehensive data on Norwegian workers, firms, and patents, we find a 50% decline in both entrepreneurship and patenting rates by university researchers after the reform. Quality measures for university start-ups and patents also decline. Applications to literatures on university technology transfer, innovation incentives, and taxes and entrepreneurship are considered.

Comment by Panorama on Open thread, Apr. 18 - Apr. 24, 2016 · 2016-04-21T10:57:13.133Z · LW · GW

Related to Disguised Queries:

Concept Creep: Psychology's Expanding Concepts of Harm and Pathology by Nick Haslam

Many of psychology's concepts have undergone semantic shifts in recent years. These conceptual changes follow a consistent trend. Concepts that refer to the negative aspects of human experience and behavior have expanded their meanings so that they now encompass a much broader range of phenomena than before. This expansion takes “horizontal” and “vertical” forms: concepts extend outward to capture qualitatively new phenomena and downward to capture quantitatively less extreme phenomena. The concepts of abuse, bullying, trauma, mental disorder, addiction, and prejudice are examined to illustrate these historical changes. In each case, the concept's boundary has stretched and its meaning has dilated. A variety of explanations for this pattern of “concept creep” are considered and its implications are explored. I contend that the expansion primarily reflects an ever-increasing sensitivity to harm, reflecting a liberal moral agenda. Its implications are ambivalent, however. Although conceptual change is inevitable and often well motivated, concept creep runs the risk of pathologizing everyday experience and encouraging a sense of virtuous but impotent victimhood.

Report about the paper in The Atlantic.

Comment by Panorama on Open Thread Feb 29 - March 6, 2016 · 2016-03-03T19:54:43.707Z · LW · GW

Cryptography Pioneers Receive 2015 ACM A.M. Turing Award

Whitfield Diffie, former Chief Security Officer of Sun Microsystems and Martin E. Hellman, Professor Emeritus of Electrical Engineering at Stanford University, are the recipients of the 2015 ACM A.M. Turing Award, for critical contributions to modern cryptography. The ability for two parties to communicate privately over a secure channel is fundamental for billions of people around the world. On a daily basis, individuals establish secure online connections with banks, e-commerce sites, email servers and the cloud. Diffie and Hellman’s groundbreaking 1976 paper, “New Directions in Cryptography,” introduced the ideas of public-key cryptography and digital signatures, which are the foundation for most regularly-used security protocols on the Internet today. The Diffie-Hellman Protocol protects daily Internet communications and trillions of dollars in financial transactions.

Comment by Panorama on Open Thread, Feb 8 - Feb 15, 2016 · 2016-02-12T11:49:10.491Z · LW · GW

Observation of Gravitational Waves from a Binary Black Hole Merger

This is the first direct detection of gravitational waves and the first observation of a binary black hole merger.

LIGO detects gravitational waves -- Press Conference

Press Release

Comment by Panorama on Open thread, Feb. 01 - Feb. 07, 2016 · 2016-02-06T22:05:00.220Z · LW · GW

Winning Arguments: Interaction Dynamics and Persuasion Strategies in Good-faith Online Discussions by Chenhao Tan, Vlad Niculae, Cristian Danescu-Niculescu-Mizil, Lillian Lee.

Changing someone's opinion is arguably one of the most important challenges of social interaction. The underlying process proves difficult to study: it is hard to know how someone's opinions are formed and whether and how someone's views shift. Fortunately, ChangeMyView, an active community on Reddit, provides a platform where users present their own opinions and reasoning, invite others to contest them, and acknowledge when the ensuing discussions change their original views. In this work, we study these interactions to understand the mechanisms behind persuasion. We find that persuasive arguments are characterized by interesting patterns of interaction dynamics, such as participant entry-order and degree of back-and-forth exchange. Furthermore, by comparing similar counterarguments to the same opinion, we show that language factors play an essential role. In particular, the interplay between the language of the opinion holder and that of the counterargument provides highly predictive cues of persuasiveness. Finally, since even in this favorable setting people may not be persuaded, we investigate the problem of determining whether someone's opinion is susceptible to being changed at all. For this more difficult task, we show that stylistic choices in how the opinion is expressed carry predictive power.

Comment by Panorama on Open thread, Feb. 01 - Feb. 07, 2016 · 2016-02-06T22:02:52.093Z · LW · GW

Evaluating gambles using dynamics by Ole Peters, Murray Gell-Mann

Gambles are random variables that model possible changes in monetary wealth. Classic decision theory transforms money into utility through a utility function and defines the value of a gamble as the expectation value of utility changes. Utility functions aim to capture individual psychological characteristics, but their generality limits predictive power. Expectation value maximizers are defined as rational in economics, but expectation values are only meaningful in the presence of ensembles or in systems with ergodic properties, whereas decision-makers have no access to ensembles and the variables representing wealth in the usual growth models do not have the relevant ergodic properties. Simultaneously addressing the shortcomings of utility and those of expectations, we propose to evaluate gambles by averaging wealth growth over time. No utility function is needed, but a dynamic must be specified to compute time averages. Linear and logarithmic "utility functions" appear as transformations that generate ergodic observables for purely additive and purely multiplicative dynamics, respectively. We highlight inconsistencies throughout the development of decision theory, whose correction clarifies that our perspective is legitimate. These invalidate a commonly cited argument for bounded utility functions.

Comment by Panorama on Open thread, Jan. 18 - Jan. 24, 2016 · 2016-01-21T20:42:45.073Z · LW · GW

Evidence for a distant giant planet in the Solar System

Recent analyses have shown that distant orbits within the scattered disk population of the Kuiper Belt exhibit an unexpected clustering in their respective arguments of perihelion. While several hypotheses have been put forward to explain this alignment, to date, a theoretical model that can successfully account for the observations remains elusive. In this work we show that the orbits of distant Kuiper Belt objects (KBOs) cluster not only in argument of perihelion, but also in physical space. We demonstrate that the perihelion positions and orbital planes of the objects are tightly confined and that such a clustering has only a probability of 0.007% to be due to chance, thus requiring a dynamical origin. We find that the observed orbital alignment can be maintained by a distant eccentric planet with mass gsim10 m⊕ whose orbit lies in approximately the same plane as those of the distant KBOs, but whose perihelion is 180° away from the perihelia of the minor bodies. In addition to accounting for the observed orbital alignment, the existence of such a planet naturally explains the presence of high-perihelion Sedna-like objects, as well as the known collection of high semimajor axis objects with inclinations between 60° and 150° whose origin was previously unclear. Continued analysis of both distant and highly inclined outer solar system objects provides the opportunity for testing our hypothesis as well as further constraining the orbital elements and mass of the distant planet.

Comment by Panorama on Open Thread, January 11-17, 2016 · 2016-01-15T20:09:14.017Z · LW · GW

Why boredom is anything but boring

Implicated in everything from traumatic brain injury to learning ability, boredom has become extremely interesting to scientists.

Comment by Panorama on Open Thread, January 11-17, 2016 · 2016-01-15T20:01:39.674Z · LW · GW

Can Economics Change Your Mind?

Economics is sometimes dismissed as more art than science. In this skeptical view, economists and those who read economics are locked into ideologically motivated beliefs—liberals versus conservatives, for example—and just pick whatever empirical evidence supports those pre-conceived positions. I say this is wrong and solid empirical evidence, even of the complicated econometric sort, changes plenty of minds.

Can economics change your mind?

Where to start? I could write a whole ongoing blog on this question (wait…). In any case, here are just a few examples of where I have changed my mind due to economic evidence:

Comment by Panorama on Open Thread, January 4-10, 2016 · 2016-01-06T16:41:51.906Z · LW · GW

Iran's blogfather: Facebook, Instagram and Twitter are killing the web

Hossein Derakhshan was imprisoned by the regime for his blogging. On his release, he found the internet stripped of its power to change the world and instead serving up a stream of pointless social trivia

Comment by Panorama on Open Thread, January 4-10, 2016 · 2016-01-06T16:04:54.891Z · LW · GW

Game Theory (Open Access textbook with 165 solved exercises) by Giacomo Bonanno.

Comment by Panorama on Open Thread, January 4-10, 2016 · 2016-01-06T16:01:52.121Z · LW · GW

Why too much evidence can be a bad thing

(Phys.org)—Under ancient Jewish law, if a suspect on trial was unanimously found guilty by all judges, then the suspect was acquitted. This reasoning sounds counterintuitive, but the legislators of the time had noticed that unanimous agreement often indicates the presence of systemic error in the judicial process, even if the exact nature of the error is yet to be discovered. They intuitively reasoned that when something seems too good to be true, most likely a mistake was made.

In a new paper to be published in The Proceedings of The Royal Society A, a team of researchers, Lachlan J. Gunn, et al., from Australia and France has further investigated this idea, which they call the "paradox of unanimity."

"If many independent witnesses unanimously testify to the identity of a suspect of a crime, we assume they cannot all be wrong," coauthor Derek Abbott, a physicist and electronic engineer at The University of Adelaide, Australia, told Phys.org. "Unanimity is often assumed to be reliable. However, it turns out that the probability of a large number of people all agreeing is small, so our confidence in unanimity is ill-founded. This 'paradox of unanimity' shows that often we are far less certain than we think."

The researchers demonstrated the paradox in the case of a modern-day police line-up, in which witnesses try to identify the suspect out of a line-up of several people. The researchers showed that, as the group of unanimously agreeing witnesses increases, the chance of them being correct decreases until it is no better than a random guess.

In police line-ups, the systemic error may be any kind of bias, such as how the line-up is presented to the witnesses or a personal bias held by the witnesses themselves. Importantly, the researchers showed that even a tiny bit of bias can have a very large impact on the results overall. Specifically, they show that when only 1% of the line-ups exhibit a bias toward a particular suspect, the probability that the witnesses are correct begins to decrease after only three unanimous identifications. Counterintuitively, if one of the many witnesses were to identify a different suspect, then the probability that the other witnesses were correct would substantially increase.

The mathematical reason for why this happens is found using Bayesian analysis, which can be understood in a simplistic way by looking at a biased coin. If a biased coin is designed to land on heads 55% of the time, then you would be able to tell after recording enough coin tosses that heads comes up more often than tails. The results would not indicate that the laws of probability for a binary system have changed, but that this particular system has failed. In a similar way, getting a large group of unanimous witnesses is so unlikely, according to the laws of probability, that it's more likely that the system is unreliable.

Comment by Panorama on Open thread, Dec. 14 - Dec. 20, 2015 · 2015-12-16T23:41:06.551Z · LW · GW

The science myths that will not die

False beliefs and wishful thinking about the human experience are common. They are hurting people — and holding back science.

Comment by Panorama on Open thread, Dec. 14 - Dec. 20, 2015 · 2015-12-16T23:40:00.737Z · LW · GW

The Strangest, Most Spectacular Bridge Collapse (And How We Got It Wrong)

Bridge building has been bedeviling humans for a long time, probably since the 1st century. That may explain why, even when they can't carry lots of people or things, bridges are particularly good at carrying lots of meaning: breaking, burning, going too far, going nowhere; the bridges between cultures, across generations, the ones we’ll cross when we come to them. To this day, however, the meanings of Gertie's collapse and that unforgettable footage—"among the most dramatic and widely known images in science and engineering," wrote one engineer—remain murky.

For physics teachers, the footage of Gertie has proved irresistible as a lesson in wave motion—and, specifically, a textbook example of the power of forced resonance. The image of the undulating bridge left its mark on scores of students (including me) as a demonstration of what one canonical version of the film calls “resonance vibrations." Since then, scores of books and articles, from Encyclopedia Britannica to a Harvard course website, have reported that the Tacoma Narrows was destroyed by resonance.

But it turns out it wasn't. And yet, while science has known that for years, lots of people (including me) apparently didn't get the memo.

Comment by Panorama on Open thread, Dec. 14 - Dec. 20, 2015 · 2015-12-16T23:23:55.255Z · LW · GW

Guess the correlation

The aim of the game is simple. try to guess how correlated the two variables in a scatter plot are. The closer your guess is to the true correlation, the better.

Comment by Panorama on Open thread, December 7-13, 2015 · 2015-12-16T23:20:43.394Z · LW · GW

Ask an unbounded question, get an uncomputable answer by Scott Aaronson

Comment by Panorama on Open thread, Dec. 14 - Dec. 20, 2015 · 2015-12-16T23:13:35.089Z · LW · GW

Notes on the Oxford IUT workshop by Brian Conrad

Since he was asked by a variety of people for his thoughts about the workshop, Brian wrote the following summary. He hopes that a non-specialist may also learn something from these notes concerning the present situation. Forthcoming articles in Nature and Quanta on the workshop will be addressed at the general public. This writeup has the following structure:

Background

What has delayed wider understanding of the ideas?

What is Inter-universal Teichmuller Theory (IUTT = IUT)?

What happened at the conference?

Audience frustration

Concluding thoughts

Technical appendix

Comment by Panorama on Open thread, December 7-13, 2015 · 2015-12-12T20:27:58.415Z · LW · GW

Please, not another bias! An evolutionary take on behavioural economics by Jason Collins

So, I want to take you to a Wikipedia page that I first saw when someone tweeted that they had found “the best page on the internet”. The “List of cognitive biases” was up to 165 entries on the day I took this snapshot, and it contains most of your behavioural science favourites … the availability heuristic, confirmation bias, the decoy effect – a favourite of marketers, the endowment effect and so on ….

But this page, to me, points to what I see as a fundamental problem with behavioural economics.

Let me draw an analogy with the history of astronomy. In 1500, the dominant model of the universe involved the sun, planets and stars orbiting around the earth.

Since that wasn’t what was actually happening, there was a huge list of deviations from this model. We have the Venus effect, where Venus appears in the evening and morning and never crosses the night sky. We have the Jupiter bias, where it moves across the night sky, but then suddenly starts going the other way.

Putting all the biases in the orbits of the planets and sun together, we end up with a picture of the orbits that looks something like this picture – epicycles on epicycles.

But instead of this model of biases, deviations and epicycles, what about an alternative model?

The earth and the planets orbit the sun.

Of course, it’s not quite as simple as this picture – the orbits of the planets around the sun are elliptical, not circular. But, essentially, by adopting this new model of how the solar system worked, a large collection of “biases” was able to become a coherent theory.

Behavioural economics has some similarities to the state of astronomy in 1500 – it is still at the collection of deviation stage. There aren’t 165 human biases. There are 165 deviations from the wrong model.

So what is this unifying theory? I suggest the first place to look is evolutionary biology. Human minds are the product of evolution, shaped by millions of years of natural selection.

Comment by Panorama on Open thread, December 7-13, 2015 · 2015-12-09T21:03:39.166Z · LW · GW

Paradox at the heart of mathematics makes physics problem unanswerable

Gödel’s incompleteness theorems are connected to unsolvable calculations in quantum physics.

Undecidability of the Spectral Gap (full version) by Toby Cubitt, David Perez-Garcia, Michael M. Wolf

We show that the spectral gap problem is undecidable. Specifically, we construct families of translationally-invariant, nearest-neighbour Hamiltonians on a 2D square lattice of d-level quantum systems (d constant), for which determining whether the system is gapped or gapless is an undecidable problem. This is true even with the promise that each Hamiltonian is either gapped or gapless in the strongest sense: it is promised to either have continuous spectrum above the ground state in the thermodynamic limit, or its spectral gap is lower-bounded by a constant in the thermodynamic limit. Moreover, this constant can be taken equal to the local interaction strength of the Hamiltonian. This implies that it is logically impossible to say in general whether a quantum many-body model is gapped or gapless. Our results imply that for any consistent, recursive axiomatisation of mathematics, there exist specific Hamiltonians for which the presence or absence of a spectral gap is independent of the axioms. These results have a number of important implications for condensed matter and many-body quantum theory.

Comment by Panorama on Open thread, Nov. 30 - Dec. 06, 2015 · 2015-12-04T19:00:09.706Z · LW · GW

User behaviour: Websites and apps are designed for compulsion, even addiction. Should the net be regulated like drugs or casinos?

When I go online, I feel like one of B F Skinner’s white Carneaux pigeons. Those pigeons spent the pivotal hours of their lives in boxes, obsessively pecking small pieces of Plexiglas. In doing so, they helped Skinner, a psychology researcher at Harvard, map certain behavioural principles that apply, with eerie precision, to the design of 21st‑century digital experiences.

Comment by Panorama on Open thread, Nov. 30 - Dec. 06, 2015 · 2015-12-04T18:42:05.404Z · LW · GW

How to build a better PhD

There are too many PhD students for too few academic jobs — but with imagination, the problem could be solved.

Comment by Panorama on Open thread, Nov. 30 - Dec. 06, 2015 · 2015-12-04T18:37:56.504Z · LW · GW

'My father had one job in his life, I've had six in mine, my kids will have six at the same time'

In the ‘gig’ or ‘sharing’ economy, say the experts, we will do lots of different jobs as technology releases us from the nine to five. But it may also bring anxiety, insecurity and low wages

Comment by Panorama on Open thread, Nov. 23 - Nov. 29, 2015 · 2015-11-26T16:45:13.777Z · LW · GW

Meta-research: Evaluation and Improvement of Research Methods and Practices by John P. A. Ioannidis , Daniele Fanelli, Debbie Drake Dunne, Steven N. Goodman.

As the scientific enterprise has grown in size and diversity, we need empirical evidence on the research process to test and apply interventions that make it more efficient and its results more reliable. Meta-research is an evolving scientific discipline that aims to evaluate and improve research practices. It includes thematic areas of methods, reporting, reproducibility, evaluation, and incentives (how to do, report, verify, correct, and reward science). Much work is already done in this growing field, but efforts to-date are fragmented. We provide a map of ongoing efforts and discuss plans for connecting the multiple meta-research efforts across science worldwide.

Comment by Panorama on [Link] A rational response to the Paris attacks and ISIS · 2015-11-24T19:39:34.332Z · LW · GW

Why People Keep Saying, “That’s What the Terrorists Want”

When President George W. Bush later responded by occupying Iraq in 2003, millions of Americans insisted that doing so was exactly what al Qaeda wanted. When, in 2004, Spain had the opposite reaction after the Madrid train bombings, and pulled back from that conflict, Americans told me that withdrawing from Iraq was actually what al-Qaeda wanted.

Today, a similar thing is happening with the Islamic State, also known as ISIS, as politicians and pundits accuse one another of “playing into the terrorists’ hands.”

How is everyone so savvy when it comes to knowing what terrorists want?

...

This also helps explain why the presumed motives of terrorists seem to shift so rapidly and contradictorily. Consider that until the Paris attacks this past week, the conventional wisdom held that the group wields violence to achieve a Caliphate unadulterated by Western interference. Since the attacks, however, we’ve been told that actually the Islamic State wants to provoke the West into more military interference in order to showcase the West’s brutal behavior. Before the attacks, we were told that France is a juicy target for the Islamic State because of its failure to integrate its Muslim population. After the attacks, we are being told that the Islamic State actually wants France and the rest of the world to become even more xenophobic against Muslims on the theory that alienated moderates may be more receptive to extremism.

It’s no wonder the media are constantly talking up terrorists as “masterminds” who commit “sophisticated” attacks. Regardless of their outcome, whatever happens will invariably be seen as exactly what the terrorists want.

It's like Texas sharpshooter fallacy by proxy.

Comment by Panorama on Open thread, Nov. 16 - Nov. 22, 2015 · 2015-11-19T22:58:05.117Z · LW · GW

Disinformation review, a weekly publication, which collects examples of the Russian disinformation attacks.

The main aim of this product is to raise the awareness about Russian disinformation campaign. And the way to achieve this goal is by providing the experts in this field, journalists, academics, officials, politicians, and anyone interested in disinformation with some real time data about the number of disinformation attacks, the number of countries targeted, the latest disinformation trends in different countries, the daily basis of this campaign, and about the coordination of the disinformation spread among many countries.

Our global network of journalists, government officials, academics, NGOs, think tanks (and other people / initiatives dealing with this issue) provides us with the examples of current disinformation appearing in their countries. East StratCom Task Force compiles their reports and publishes a weekly review of them. The document with the data collected is public and free for further use – journalists may use it as a source for their products, decision makers and government officials may find relevant information about the latest state of events, experts may find data for their analysis, NGOs and think tanks may share the knowledge about this issue with the rest of the world.

Comment by Panorama on Open thread, Nov. 16 - Nov. 22, 2015 · 2015-11-19T22:45:12.924Z · LW · GW

Feeling like you're an expert can make you closed-minded

Victor Ottati at Loyola University and his colleagues manipulated their participants (US residents, average age in their 30s) to feel relative experts or novices in a chosen field, through easy questions like “Who is the current President of the United States?” or tough ones like “Who was Nixon's initial Vice-President?” and through providing feedback to enforce the participants’ feelings of knowledge or ignorance. Those participants manipulated to feel more expert subsequently acted less open-minded toward the same topic, as judged by their responses to items such as “I am open to considering other political viewpoints.”

People’s perceptions of their all-round expertise – provoked in the participants via an easy rather than a hard trivia quiz – also led them to display a close-mindedness in general, even though it was the participants who took the hard quiz who failed more, and reported feeling more insecure, irritable and negative – ingredients that are normally associated with close-mindedness. This isn’t to say that these emotional states didn’t have any effect, just that any effect was swamped by perceptions of expertise.

Comment by Panorama on Open thread, Nov. 16 - Nov. 22, 2015 · 2015-11-19T22:37:03.834Z · LW · GW

A Quasipolynomial Time Algorithm for Graph Isomorphism: The Details

Laszlo Babai has claimed an astounding theorem, that the Graph Isomorphism problem can be solved in quasipolynomial time. On Tuesday I was at Babai’s talk on this topic (he has yet to release a preprint), and I’ve compiled my notes here. As in Babai’s talk, familiarity with basic group theory and graph theory is assumed, and if you’re a casual (i.e., math-phobic) reader looking to understand what the fuss is all about, this is probably not the right post for you. This post is research level theoretical computer science. We’re here for the juicy, glorious details.

Video of Laszlo Babai's talk.

Comment by Panorama on Open thread, Nov. 02 - Nov. 08, 2015 · 2015-11-05T22:30:52.975Z · LW · GW

Gene editing saves girl dying from leukaemia in world first

For the first time ever, a person’s life has been saved by gene editing.

...

Layla’s doctors got permission to use an experimental form of gene therapy using genetically engineered immune cells from a donor. Within a month these cells had killed off all the cancerous cells in her bone marrow.

Comment by Panorama on Open thread, Nov. 02 - Nov. 08, 2015 · 2015-11-05T20:46:51.806Z · LW · GW

Is Economics Research Replicable? Sixty Published Papers from Thirteen Journals Say “Usually Not” by Andrew C. Chang and Phillip Li

We attempt to replicate 67 papers published in 13 well-regarded economics journals using author-provided replication files that include both data and code. Some journals in our sample require data and code replication files, and other journals do not require such files. Aside from 6 papers that use confidential data, we obtain data and code replication files for 29 of 35 papers (83%) that are required to provide such files as a condition of publication, compared to 11 of 26 papers (42%) that are not required to provide data and code replication files. We successfully replicate the key qualitative result of 22 of 67 papers (33%) without contacting the authors. Excluding the 6 papers that use confidential data and the 2 papers that use software we do not possess, we replicate 29 of 59 papers (49%) with assistance from the authors. Because we are able to replicate less than half of the papers in our sample even with help from the authors, we assert that economics research is usually not replicable. We conclude with recommendations on improving replication of economics research.

Comment by Panorama on Open thread, Nov. 02 - Nov. 08, 2015 · 2015-11-05T20:38:06.192Z · LW · GW

Zombie physics: 6 baffling results that just won't die

To celebrate Halloween, Nature brings you the undead results that physicists can neither prove — nor lay to rest.

When a scientific result seems to show something genuinely new, subsequent experiments are supposed to either confirm it — triggering a textbook rewrite — or show it to be a measurement anomaly or experimental blunder. But some findings seem to remain forever stuck in the middle ground between light and shadow. Even efforts to replicate these results — normally science’s equivalent of Valyrian steel — have little effect. Welcome to the realm of undead physics.

Ahead of Halloween, Nature guides you through some findings in physics, astronomy and cosmology that researchers have repeatedly left for dead — only to find that they keep coming back.

Comment by Panorama on Open thread, Nov. 02 - Nov. 08, 2015 · 2015-11-05T20:32:15.878Z · LW · GW

NASA Study: Mass Gains of Antarctic Ice Sheet Greater than Losses

A new NASA study says that an increase in Antarctic snow accumulation that began 10,000 years ago is currently adding enough ice to the continent to outweigh the increased losses from its thinning glaciers.

The research challenges the conclusions of other studies, including the Intergovernmental Panel on Climate Change’s (IPCC) 2013 report, which says that Antarctica is overall losing land ice.

According to the new analysis of satellite data, the Antarctic ice sheet showed a net gain of 112 billion tons of ice a year from 1992 to 2001. That net gain slowed to 82 billion tons of ice per year between 2003 and 2008.

“We’re essentially in agreement with other studies that show an increase in ice discharge in the Antarctic Peninsula and the Thwaites and Pine Island region of West Antarctica,” said Jay Zwally, a glaciologist with NASA Goddard Space Flight Center in Greenbelt, Maryland, and lead author of the study, which was published on Oct. 30 in the Journal of Glaciology. “Our main disagreement is for East Antarctica and the interior of West Antarctica – there, we see an ice gain that exceeds the losses in the other areas.” Zwally added that his team “measured small height changes over large areas, as well as the large changes observed over smaller areas.”

Comment by Panorama on Open thread, Nov. 02 - Nov. 08, 2015 · 2015-11-05T20:10:50.014Z · LW · GW

Laszlo Babai (University of Chicago): Graph Isomorphism in Quasipolynomial Time (Combinatorics and TCS seminar)

We outline an algorithm that solves the Graph Isomorphism (GI) problem and the related problems of String Isomorphism (SI) and Coset Intersection (CI) in quasipolynomial (exp(polylog n)) time.

The best previous bound for GI was \exp(\sqrt{n log n}), where n is the number of vertices (Luks, 1983). For SI and CI the best previous bound was similar, \exp(\sqrt{n}(log n)^c), where n is the size of the permutation domain (the speaker, 1983).

G. Phi. Fo. Fum. by Scott Aaronson

Earlier today, I was tipped off to what might be the theoretical computer science result of the decade. My source asked me not to break the news on this blog—but since other theory bloggers (and twitterers) are now covering the story, I guess the graph is out of the Babai.

According to the University of Chicago’s theory seminar calendar, on Tuesday of next week (November 10), the legendary Laszlo Babai will be giving a talk about a new algorithm that solves the graph isomorphism problem in quasipolynomial time. The previous fastest algorithm to decide whether two n-vertex graphs G and H are isomorphic—by Babai and Luks, back in 1983—ran in exp(√(n log n)) time. If we credit the announcement, Babai has now gotten that down to exp(polylog(n)), putting one of the central problems of computer science “just barely above P.” (For years, I’ve answered questions on this blog about the status of graph isomorphism—would I bet that it’s in BQP? in coNP? etc.—by saying that, as far as I and many others are concerned, it might as well just be in P. Of course I’m happy to reaffirm that conjecture tonight.)

Comment by Panorama on Open thread, Oct. 26 - Nov. 01, 2015 · 2015-10-28T12:10:22.046Z · LW · GW

The Tech Elite’s Quest to Reinvent School in Its Own Image

A Day in the Life

Like a true startup, Khan Lab School constantly changes its schedule to accommodate evolving workflow and logistical demands. Different age-groups follow different self-paced lesson plans, but here’s an example of a day at the Lab School.

9–9:15 am: Morning Meeting

A daily all-school meeting where students learn about things like current events, view the work of their fellow classmates, and focus on relationships.

9:15–9:45 Advisory

Students break out into cohorts sorted by age. They attend one-on-one meetings with advisers to set personal goals. (One ambitious 12-year-old hopes to launch a small-scale NGO.) Some days include “Goal Studio” time to work on these independent passion projects.

9:45–10:45 Literacy Lab, Part 1

Teachers cover all the essentials, from developing main ideas to composing blog posts.

10:45–11 Morning Break

11–11:30 Literacy Lab, Part 2

Instructors use digital tools like Lexia and LightSail to assess students’ reading levels and work with individuals on problem areas.

11:30–12 Inner Wellness

Students improve their mental well-being by practicing mindfulness.

12–12:45 pm Lunch

12:45–1 Afternoon Meeting

Another schoolwide gathering for announcements and updates.

1–2:30 Math/Computer Science Lab

Using videos from Khan Academy, students practice skills at their math level. Younger students receive more direct instruction, while older students might work on a collaborative engineering project.

2:30–3 Outer Wellness

Students participate in physical fitness activities, including gardening and playing sports like field hockey, soccer, and Ultimate Frisbee.

3–4 Cleanup, Read Aloud, Flexible Pick Up/Recess

4–6 Studio Time/Pick Up

During this optional period, students work on their own without direct supervision, though the staff is available for help.

Comment by Panorama on Open thread, Oct. 26 - Nov. 01, 2015 · 2015-10-28T11:57:41.359Z · LW · GW

The Way to Help the Poor by Dean Karlan

You can't make money without money. That was the exciting and intuitively obvious idea behind microloans, which took off in the 1990s as a way of helping poor people out of poverty. Banks wouldn't give them traditional loans, but small amounts would carry less risk and allow entrepreneurs to jump-start small businesses. Economist Muhammad Yunus and Bangladesh's Grameen Bank figured out how to scale this innovation and won the 2006 Nobel Peace Prize for their work.

The trouble is that although microloans do have some benefits, recent evidence suggests that on average they increase neither income nor household and food expenditures—key indicators of financial well-being.

That a program could be celebrated for more than 20 years and lavished with money and still fail to help people out of poverty underscores the paucity of evidence in antipoverty programs. Individual Americans, for instance, spend $335 billion a year on charity, yet most people give on impulse or a friend's recommendation—not because they have evidence that their giving will do any good. Philanthropies also often give money to projects without really knowing if they are successful.

Fortunately, we are living in the age of big data: decisions that used to be made on instinct can now be based on solid evidence. In recent years social scientists have begun to marshal the tools of big data to ask the hard questions about what works and what doesn't. The goal is to turn philanthropy into a science, where money gets directed to programs for which there is strong evidence of their effectiveness.

Comment by Panorama on Open thread, Oct. 26 - Nov. 01, 2015 · 2015-10-28T11:48:54.683Z · LW · GW

A multi-institutional study of the impact of open textbook adoption on the learning outcomes of post-secondary students

In some educational settings, the cost of textbooks approaches or even exceeds the cost of tuition. Given limited resources, it is important to better understand the impacts of free open educational resources (OER) on student outcomes. Utilizing digital resources such as OER can substantially reduce costs for students. The purpose of this study was to analyze whether the adoption of no-cost open digital textbooks significantly predicted students’ completion of courses, class achievement, and enrollment intensity during and after semesters in which OER were used. This study utilized a quantitative quasi-experimental design with propensity-score matched groups to examine differences in outcomes between students that used OER and those who did not. The demographics of the initial sample of 16,727 included 4909 students in the treatment condition with a pool of 11,818 in the control condition. There were statistically significant differences between groups, with most favoring students utilizing OER.

Comment by Panorama on Open thread, Oct. 26 - Nov. 01, 2015 · 2015-10-28T11:40:08.231Z · LW · GW

Glaring Flaws in Sugar Toxicity Study

A new study has claimed that obese children could find rapid health improvement by small sugar reductions, without caloric restrictions. According to the lead author, Robert Lustig, the new study shows that sugar may not be harmful because of how it leads to weight gain, but “rather sugar is metabolically harmful because it’s sugar.” According to the study, a diet with 10 percent sugar in place of one with 28 percent sugar can in just nine days produce a reduction in blood pressure, triglycerides and LDL-cholesterol—and improved glucose tolerance and lower levels of insulin circulating in the blood.

Does a miracle diet promising incredible results in just nine days sound too good to be true? Not to the news media, which gobbled up the study’s conclusions as the proof that sugar really is the big evil in our diet (see sidebar). But as we shall see, the science in the study is about as good as it is for other fad diets.

Comment by Panorama on Open thread, Oct. 26 - Nov. 01, 2015 · 2015-10-28T11:35:48.201Z · LW · GW

Carol Dweck Revisits the 'Growth Mindset' by Carol Dweck.

Recently, someone asked what keeps me up at night. It’s the fear that the mindset concepts, which grew up to counter the failed self-esteem movement, will be used to perpetuate that movement. In other words, if you want to make students feel good, even if they’re not learning, just praise their effort! Want to hide learning gaps from them? Just tell them, “Everyone is smart!” The growth mindset was intended to help close achievement gaps, not hide them. It is about telling the truth about a student’s current achievement and then, together, doing something about it, helping him or her become smarter.

Comment by Panorama on Open thread, Oct. 19 - Oct. 25, 2015 · 2015-10-23T13:19:29.712Z · LW · GW

Autonomous Vehicles Need Experimental Ethics: Are We Ready for Utilitarian Cars?

The wide adoption of self-driving, Autonomous Vehicles (AVs) promises to dramatically reduce the number of traffic accidents. Some accidents, though, will be inevitable, because some situations will require AVs to choose the lesser of two evils. For example, running over a pedestrian on the road or a passer-by on the side; or choosing whether to run over a group of pedestrians or to sacrifice the passenger by driving into a wall. It is a formidable challenge to define the algorithms that will guide AVs confronted with such moral dilemmas. In particular, these moral algorithms will need to accomplish three potentially incompatible objectives: being consistent, not causing public outrage, and not discouraging buyers. We argue to achieve these objectives, manufacturers and regulators will need psychologists to apply the methods of experimental ethics to situations involving AVs and unavoidable harm. To illustrate our claim, we report three surveys showing that laypersons are relatively comfortable with utilitarian AVs, programmed to minimize the death toll in case of unavoidable harm. We give special attention to whether an AV should save lives by sacrificing its owner, and provide insights into (i) the perceived morality of this self-sacrifice, (ii) the willingness to see this self-sacrifice being legally enforced, (iii) the expectations that AVs will be programmed to self-sacrifice, and (iv) the willingness to buy self-sacrificing AVs.

Comment by Panorama on Open thread, Oct. 19 - Oct. 25, 2015 · 2015-10-23T10:26:00.758Z · LW · GW

The scientists encouraging online piracy with a secret codeword

What if you're a scientist looking for the latest published research on a particular subject, but you can't afford to pay for it?

...

Andrea Kuszewski, a cognitive scientist and science writer, invented the tag, which uses a code phrase: "I can haz PDF" - a play on words combining a popular geeky phrase used widely online in a meme involving cat pictures, and a common online file format.

"Basically you tweet out a link to the paper that you need, with the hashtag and then your email address," she told BBC Trending radio. "And someone will respond to your email and send it to you." Who might that "someone" be? Kuszewski says scientists who have access to journals, through subscriptions or the institutions they work at, look out for the tag so they can help out colleagues in need.

Comment by Panorama on Open thread, Oct. 19 - Oct. 25, 2015 · 2015-10-23T10:16:30.806Z · LW · GW

'Zeno effect' verified: Atoms won't move while you watch

One of the oddest predictions of quantum theory – that a system can’t change while you’re watching it – has been confirmed in an experiment by Cornell physicists.

...

Graduate students Yogesh Patil and Srivatsan K. Chakram created and cooled a gas of about a billion Rubidium atoms inside a vacuum chamber and suspended the mass between laser beams. In that state the atoms arrange in an orderly lattice just as they would in a crystalline solid.,But at such low temperatures, the atoms can “tunnel” from place to place in the lattice. The famous Heisenberg uncertainty principle says that the position and velocity of a particle interact. Temperature is a measure of a particle’s motion. Under extreme cold velocity is almost zero, so there is a lot of flexibility in position; when you observe them, atoms are as likely to be in one place in the lattice as another.

...

The researchers observed the atoms under a microscope by illuminating them with a separate imaging laser. A light microscope can’t see individual atoms, but the imaging laser causes them to fluoresce, and the microscope captured the flashes of light. When the imaging laser was off, or turned on only dimly, the atoms tunneled freely. But as the imaging beam was made brighter and measurements made more frequently, the tunneling reduced dramatically.

Comment by Panorama on Open thread, Oct. 19 - Oct. 25, 2015 · 2015-10-23T10:12:43.752Z · LW · GW

UN climate reports are increasingly unreadable

The climate summary findings of the Intergovernmental Panel on Climate Change (IPCC) are becoming increasingly unreadable, a linguistics analysis suggests.

IPCC summaries are intended for non-scientific audiences. Yet their readability has dropped over the past two decades, and reached a low point with the fifth and latest summary published in 2014, according to a study published in Nature Climate Change1.

The study used the Flesch Reading Ease test, which assumes that texts with longer sentences and more complex words are harder to read. Reports from the IPCC’s Working Group III, which focuses on what can be done to mitigate climate change by cutting carbon dioxide emissions, received the lowest marks for readability.

Confusion created by the writing style of the summaries could hamper political progress on tackling greenhouse-gas emissions, thinks Ralf Barkemeyer, who led the analysis and works on sustainable business management at the KEDGE Business School in Bordeaux, France. The readability scores “are not just low but exceptionally low”, he says.

Comment by Panorama on Open thread, Oct. 19 - Oct. 25, 2015 · 2015-10-23T10:09:20.862Z · LW · GW

Final Kiss of Two Stars Heading for Catastrophe

Using ESO’s Very Large Telescope, an international team of astronomers have found the hottest and most massive double star with components so close that they touch each other. The two stars in the extreme system VFTS 352 could be heading for a dramatic end, during which the two stars either coalesce to create a single giant star, or form a binary black hole.

Comment by Panorama on Open thread, Oct. 12 - Oct. 18, 2015 · 2015-10-12T16:10:55.675Z · LW · GW

Blowing the whistle on the uc berkeley mathematics department

This remark that I should align more with department standards has been the resounding theme of my time at Berkeley, and Arthur Ogus's comment in the April 18th, 2014 memo was not an isolated slip. On September 22nd, 2013 he wrote in an email "But I do think it that it [sic] is very important that you not deviate too far from the department norms." On November 12th, 2014 he wrote "I hope that, on the basis of our conversation, you can further adjust to the norms of our department." This raises the question: What does it mean to adhere to department norms if one has the highest student evaluation scores in the department, students performing statistically significantly better in subsequent courses, and faculty observations universally reporting "extraordinary skills at lecturing, presentation, and engaging students"?

This question is one that I asked, and in response it was made very clear to me what is meant by the norms of the department. It means teach from the textbook. It means stop emailing students with encouragement, handwritten notes and homework problems, and instead assign problems from the textbook at the start of the semester. It means stop using evidence-based practices like formative assessment. It means micro-manage the Graduate Student Instructors rather than allowing them to use their own, considerable, talent and creativity. And most of all it means this: Stop motivating students to work hard and attend class by being engaging, encouraging and inspiring, by sharing with them a passion for the beauty and wonder of mathematics, but instead by forcing them into obedience with endless busywork in the form of GPA-affecting homework and quizzes and assessments, day after day, semester after semester.

In a nutshell: Stop making us look bad. If you don't, we'll fire you.

Comment by Panorama on Open thread, Sep. 21 - Sep. 27, 2015 · 2015-09-25T15:28:28.252Z · LW · GW

How Soylent and Oculus Could Fix The Prison System

here’s one way we could rebuild the prison system:

Step 1: Soylent

Step 2: Oculus Rift

Step 3: Health and hygiene

Step 4: A simulation that rewards good behavior

Step 5: Administration

Excerpt:

Prisoners have cellmates and gym time and free time in the prison yard because solitary confinement makes you go nuts. You need human contact if you don’t want to pop out of prison a crazy person. The problem is these places are where all the violence happens.

However, you could take the fear factor out of prisons by simply making all socialization happen through virtual reality. Bonus, you could deliver rich education through VR as well.

Virtual reality headsets are so good now (and getting better) that they can make your brain feel like you’re actually somewhere else. I get the same feeling in the pit of my stomach when I’m standing on a cliff in virtual reality as I do when I’m experiencing heights IRL.

By equipping every inmate with an Oculus Rift headset in his or her own cell, you could isolate prisoners from violence without isolating them from people. Put all the prisoners inside Second Life, Prison Edition, give them all a headset, and let them build virtual characters. You could design an awesome system for rehabilitation, give access to e-learning tools, Kindle books, Minecraft and other digital tools for creativity (prison is boring), psychologist sessions (the psychologist could log in remotely from anywhere in the world), and even handle all correspondence and prison visits from relatives and friends electronically.

What this eliminates: prison yards, prison libraries, packages and letters secretly containing drugs or shanks.

Comment by Panorama on Open thread, Sep. 14 - Sep. 20, 2015 · 2015-09-14T21:14:52.379Z · LW · GW

26 Things I Learned in the Deep Learning Summer School

In the beginning of August I got the chance to attend the Deep Learning Summer School in Montreal. It consisted of 10 days of talks from some of the most well-known neural network researchers. During this time I learned a lot, way more than I could ever fit into a blog post. Instead of trying to pass on 60 hours worth of neural network knowledge, I have made a list of small interesting nuggets of information that I was able to summarise in a paragraph.

At the moment of writing, the summer school website is still online, along with all the presentation slides. All of the information and most of the illustrations come from these slides and are the work of their original authors. The talks in the summer school were filmed as well, hopefully they will also find their way to the web.

Comment by Panorama on Open thread, Sep. 14 - Sep. 20, 2015 · 2015-09-14T21:12:38.798Z · LW · GW

The Fallacy of Placing Confidence in Confidence Intervals

Welcome to the web site for the upcoming paper "The Fallacy of Placing Confidence in Confidence Intervals." Here you will find a number of resources connected to the paper, including the itself, the supplement, teaching resources and in the future, links to discussion of the content.

The paper is accepted for publication in Psychonomic Bulletin & Review.

pdf

Interval estimates – estimates of parameters that include an allowance for sampling uncertainty – have long been touted as a key component of statistical analyses. There are several kinds of interval estimates, but the most popular are confidence intervals (CIs): intervals that contain the true parameter value in some known proportion of repeated samples, on average. The width of confidence intervals is thought to index the precision of an estimate; CIs are thought to be a guide to which parameter values are plausible or reasonable; and the confidence coefficient of the interval (e.g., 95%) is thought to index the plausibility that the true parameter is included in the interval. We show in a number of examples that CIs do not necessarily have any of these properties, and can lead to unjustified or arbitrary inferences. For this reason, we caution against relying upon confidence interval theory to justify interval estimates, and suggest that other theories of interval estimation should be used instead

Comment by Panorama on Open thread 7th september - 13th september · 2015-09-08T20:00:17.285Z · LW · GW

A redditor has created a .docx document that summarizes which studies have been replicated in recent big psychology replication study.