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Physicist, Startup Founder, Blogger, Dad

Thursday, March 31, 2016

Khruangbin



New Yorker: ... Khruangbin plays a spellbinding twist on surf rock and soul that would be considered trite if it weren’t so appetizing. The band’s origins are delightfully nerdy: Speer bonded with the bassist Laura Lee and the drummer Donald Johnson over lo-fi digital rips of cassette tapes featuring obscure Thai funk bands from the sixties and seventies, which they’d downloaded from the cult blog Monrakplengthai. The cassette tapes catalogue stray releases from Thai musicians who, influenced by imported rock records from bands like Santana and the Shadows, blended the misty, coiling guitars of foundational rock and roll with the melodic sensibilities of their own traditional folk tunes. Many of the songs were used in Bollywood films, reaching wide swaths of Southeast Asian audiences. “Shadow music,” as the sound came to be called, is exhilarating in part for its traceable roots. Several cuts would fit seamlessly into your favorite countercultural film score, were it not for vocalists unspooling lyrics in their native tongue.

Speer, Lee, and Johnson would return to these tapes sporadically when they gathered in a barn in Burton, Texas (in addition to conferring via Skype when Lee briefly relocated to London), to write and record “Universe.” (The band’s name means “airplane” in Thai, but none of the members claim roots in the South Asian country.) ...



Tuesday, March 29, 2016

The Butlerian Jihad and Darwin among the Machines


Left: Samuel Butler, Right: Frank Herbert.

And when that which was foretold shall come to pass, for behold it is coming, then shall they know that a prophet hath been among them. -- Ezekiel 33:33

See also Don't worry -- smart machines will take us with them, and Philip K. Dick's first science fiction story.
Butlerian Jihad (Wikipedia): The Butlerian Jihad is an event in the back-story of Frank Herbert's fictional Dune universe. Occurring over 10,000 years before the events chronicled in his 1965 novel Dune, this jihad leads to the outlawing of certain technologies, primarily "thinking machines," a collective term for computers and artificial intelligence of any kind. This prohibition is a key influence on the nature of Herbert's fictional setting.
... "The target of the Jihad was a machine-attitude as much as the machines," Leto said. "Humans had set those machines to usurp our sense of beauty, our necessary selfdom out of which we make living judgments. Naturally, the machines were destroyed."
... The chief commandment from the Orange Catholic Bible, "Thou shalt not make a machine in the likeness of a human mind", holds sway, as do the anti-artificial intelligence laws in which the penalty for owning an AI device or developing technology resembling the human mind is immediate death. This leads to the rise of a new feudalistic galactic empire which lasts for over ten thousand years. ...

To replace the analytical powers of computers without violating the commandment of the O.C. Bible, "human computers" known as Mentats are developed and perfected, their mental abilities ultimately honed to the point where they become superior to those of the ancient thinking machines. Similarly specialized groups of humans which arise after the Jihad include the Bene Gesserit, a matriarchal order with advanced mental and physical abilities, and the Spacing Guild, whose prescience makes safe, instantaneous space travel possible.
19th-century author Samuel Butler introduced the idea of evolved machines supplanting mankind as the dominant species in his 1863 article "Darwin among the Machines" and later works. Butler goes on to suggest that all machines be immediately destroyed to avoid this outcome.
Darwin among the Machines (Wikipedia): ... article published in The Press newspaper on 13 June 1863 in Christchurch, New Zealand. Written by Samuel Butler but signed Cellarius (q.v.), the article raised the possibility that machines were a kind of "mechanical life" undergoing constant evolution, and that eventually machines might supplant humans as the dominant species:
We refer to the question: What sort of creature man’s next successor in the supremacy of the earth is likely to be. We have often heard this debated; but it appears to us that we are ourselves creating our own successors; we are daily adding to the beauty and delicacy of their physical organisation; we are daily giving them greater power and supplying by all sorts of ingenious contrivances that self-regulating, self-acting power which will be to them what intellect has been to the human race. In the course of ages we shall find ourselves the inferior race. ...

Day by day, however, the machines are gaining ground upon us; day by day we are becoming more subservient to them; more men are daily bound down as slaves to tend them, more men are daily devoting the energies of their whole lives to the development of mechanical life. The upshot is simply a question of time, but that the time will come when the machines will hold the real supremacy over the world and its inhabitants is what no person of a truly philosophic mind can for a moment question.
The article ends by urging that, "War to the death should be instantly proclaimed against them. Every machine of every sort should be destroyed by the well-wisher of his species. Let there be no exceptions made, no quarter shown; let us at once go back to the primeval condition of the race."

Sunday, March 27, 2016

Science vs Advocacy: the benefits of diversity

This manuscript is based on the Presidential Address that Alice H. Eagly (Professor of Psychology and of Management at Northwestern University) delivered at the 2015 conference of the Society for the Psychological Study of Social Issues, “A Road Less Traveled: Forging Links between Psychological Science and Social Policy,” Washington, DC.
When Passionate Advocates Meet Research on Diversity, Does the Honest Broker Stand a Chance?

Journal of Social Issues, 72: 199–222. doi: 10.1111/josi.12163

Abstract: In an ideal world, social science research would provide a strong basis for advocacy and social policy. However, advocates sometimes misunderstand or even ignore scientific research in pursuit of their goals, especially when research pertains to controversial questions of social inequality. To illustrate the chasm that can develop between research findings and advocates’ claims, this article addresses two areas: (a) the effects of the gender diversity of corporate boards of directors on firms’ financial performance and (b) the effects of the gender and racial diversity of workgroups on group performance. Despite advocates’ insistence that women on boards enhance corporate performance and that diversity of task groups enhances their performance, research findings are mixed, and repeated meta-analyses have yielded average correlational findings that are null or extremely small. Therefore, social scientists should (a) conduct research to identify the conditions under which the effects of diversity are positive or negative and (b) foster understanding of the social justice gains that can follow from diversity. Unfortunately, promulgation of false generalizations about empirical findings can impede progress in both of these directions. Rather than ignoring or furthering distortions of scientific knowledge to fit advocacy goals, scientists should serve as honest brokers who communicate consensus scientific findings to advocates and policy makers in an effort to encourage exploration of evidence-based policy options.
From the paper
... Establishing that the presence of women on corporate boards causes any of the positive or negative outcomes is far more challenging (see Adams, 2015). As in many other domains of nonexperimental research, relatively few researchers have addressed endogeneity in a manner that allows claims about causation (Antonakis, Bendahan, Jacquart, & Lalive, 2010). However, the “business case”—that is, the boldly causal claim that including women on corporate boards improves firms’ financial outcomes, lives on in communications directed to the public and business community (e.g., Committee for Economic Development, 2015), most often supported by citations of the least informative studies, which are those containing only simple group comparisons (e.g., Catalyst, 2004; Desvaux et al., 2007).

... Over the years, a very large research literature has accumulated relating workgroup diversity to group performance, published in academic journals mainly in industrial-organizational psychology and management. These investigators have distinguished two types of diversity: job-related, which pertains to differences in knowledge and expertise related to the problems that work groups are charged with solving, and demographic, which pertains to differences in attributes such as gender, race, and age (e.g., Mannix & Neale, 2005). Research has extensively examined both of these forms of diversity.

Several meta-analyses of the diversity-performance relation have been prominently published, with the latest and most inclusive produced by van Dijk, van Engen, and van Knippenberg (2012). Among this project's 146 studies, there were three types of settings: (a) laboratory experiments (b) field studies, and (c) studies conducted on teams composed of undergraduate or MBA students. These field and student studies generally provided correlational data relating amount of diversity to group performance. The finding that the classification of studies by these three types of settings did not moderate diversity-performance relations eases concerns about endogeneity, given the greater ability of the laboratory experiments to rule out alternative explanations based on uncontrolled variables.

The meta-analysis produced mainly very small average effect sizes: The key overall findings were that demographic diversity yielded a small negative relation to performance outcomes (r = –.02), which was present for both gender diversity (r = –.01) and racial/ethnic diversity (r = –.05); all of these relations were nonsignificant. In contrast, job-related diversity produced a significant, but small, positive relation (r = .05). These findings replicated four prior meta-analyses based on smaller samples of studies (Bell, Villado, Lukasik, Belau, & Briggs, 20100; Horwitz & Horwitz, 2007; Hülsheger, Anderson, & Salgado, 2009; Joshi & Roh, 2009). In addition, a meta-analysis of 68 studies produced a nonsignificant relation between gender diversity and team performance (r = -.01; Schneid, Isidor, Li, & Kabst, 2015). Moreover, these meta-analytic results were generally consistent with earlier narrative reviewers’ cautions that demographic diversity had yielded mixed and inconclusive effects (Harrison & Klein, 2007; Mannix & Neale, 2005; Milliken & Martins, 1996; Williams & O'Reilly, 1998).

... In summary, when aggregated across studies, an extensive research literature on group performance has shown no overall advantage for demographically diverse groups, with a small tendency toward disadvantage, especially on subjective measures of performance. However, these meta-analytic averages encompassed heterogeneous outcomes, whereby some studies did produce positive effects of diversity. Yet, approximately as many studies yielded negative effects, producing average effects that were near zero. In this respect, these findings are similar to the correlations between the representation of women as corporate directors and financial outcomes.
Concluding paragraph
To conclude, this article conveys some ways in which science, advocacy, and policy have not related easily or harmoniously. I have told two somewhat complicated stories, one pertaining to women on corporate boards and the other to workgroup diversity—two domains with extensive social scientific research relating diversity to performance outcomes. Despite the striking lack of research support for the optimistic generalizations about these outcomes that have been widely shared among advocates, policy makers, and the general public, many social scientists with relevant expertise have remained silent. It is time for more social scientists to take stock of what diversity research has produced so far and join those who are addressing the complexities of diversity's effects on group and organizational performance. It is also time for all stakeholders in diversity initiatives to focus on the violations of social justice inherent in the limited access of women and minorities to decision making in most political and corporate contexts.

Saturday, March 26, 2016

Sprockets Haus




Genetic ancestry and brain morphology


Population structure -- i.e., distribution of gene variants by ancestral group -- is reflected in brain morphology, as measured using MRI. Brain morphology measurements can be used to predict ancestry. Strictly speaking, the data only show correlation, not genetic causation, but the most plausible interpretation is that genetic differences are causing morphological differences. One could check this easily by comparing individuals raised in different environments and cultures.

See also Heritability of brain structure, IQ prediction from structural MRI, and Metabolic costs of human brain development.

Most of the authors are associated with UCSD. From the paper:
PING (Pediatric Imaging, Neurocognition, and Genetics) was a multisite project recruiting children and adolescents from ages 3 to 21 at ten sites in the United States. All participants were screened for history of major developmental, psychiatric, and neurological disorders; brain injury; and other medical conditions that affect development. Participants then received neurodevelopmental assessments, standardized multi-modal neuroimaging, and genome-wide genotyping. The overall PING sample consisted of 1,493 participants; 1,152 individuals remained after quality control of the genotyping and neuroimaging data.

... Our data indicate that the unique folding patterns of gyri and sulci are closely aligned with genetic ancestry. The geometry robustly predicts each individual’s genetic background even though the population has been shaped by waves of migration and admixtures. A previous study, using only facial features, achieved 64% explained variance in YRI ancestry among African Americans [19]. Our 3D representation of cortical surface geometry performs similarly in predicting YRI ancestry and also performs well for the other three continental ancestries. As data in Table 1 show, the explanatory power is not due to the differences in total brain volumes, nor to the differences in areal expansion of the cortical surface. Instead, regional folding patterns characterize each ancestral lineage. ...

Modeling the 3D Geometry of the Cortical Surface with Genetic Ancestry

Chun Chieh Fan, Hauke Bartsch, Andrew J. Schork, Chi-Hua Chen, Yunpeng Wang, Min-Tzu Lo, Timothy T. Brown, Joshua M. Kuperman, Donald J. Hagler Jr., Nicholas J. Schork, Terry L. Jernigan, Anders M. Dale, the Pediatric Imaging, Neurocognition, and Genetics Study

Cell: Current Biology 25, 1–5 August 3, 2015
http://dx.doi.org/10.1016/j.cub.2015.06.006

Highlights
•Geometry of the human cortical surface contains rich ancestral information
•The most informative features are regional patterns of cortical folding and gyrification
•This study provides insight on the influence of population structure on brain shape

Summary
Knowing how the human brain is shaped by migration and admixture is a critical step in studying human evolution [1, 2], as well as in preventing the bias of hidden population structure in brain research [3, 4]. Yet, the neuroanatomical differences engendered by population history are still poorly understood. Most of the inference relies on craniometric measurements, because morphology of the brain is presumed to be the neurocranium’s main shaping force before bones are fused and ossified [5]. Although studies have shown that the shape variations of cranial bones are consistent with population history [6–8], it is unknown how much human ancestry information is retained by the human cortical surface. In our group’s previous study, we found that area measures of cortical surface and total brain volumes of individuals of European descent in the United States correlate significantly with their ancestral geographic locations in Europe [9]. Here, we demonstrate that the three-dimensional geometry of cortical surface is highly predictive of individuals’ genetic ancestry in West Africa, Europe, East Asia, and America, even though their genetic background has been shaped by multiple waves of migratory and admixture events. The geometry of the cortical surface contains richer information about ancestry than the areal variability of the cortical surface, independent of total brain volumes. Besides explaining more ancestry variance than other brain imaging measurements, the 3D geometry of the cortical surface further characterizes distinct regional patterns in the folding and gyrification of the human brain associated with each ancestral lineage.

This figure shows ancestry admixture using PCA. The figure at top shows that brain morphological parameters can be used to build a reasonably good classifier.

Friday, March 25, 2016

Genetic links between autism and typical variation in social behavior and adaptive function


The genetic etiology of autism is starting to become better understood. Common as well as rare variants are known to contribute to risk. ASD exists in the tail of a spectrum of behavioral traits, and sub-threshold traits are more likely to be found in relatives of an individual diagnosed with ASD. The paper reports a genetic correlation of 0.4 between ASD and IQ, which suggests that many ASD variants also affect general cognitive function (Supplement).

See also De novo mutations and autism and Disruptive mutations and the genetic architecture of autism.
Genetic risk for autism spectrum disorders and neuropsychiatric variation in the general population

Nature Genetics (2016) doi:10.1038/ng.3529

Almost all genetic risk factors for autism spectrum disorders (ASDs) can be found in the general population, but the effects of this risk are unclear in people not ascertained for neuropsychiatric symptoms. Using several large ASD consortium and population-based resources (total n > 38,000), we find genome-wide genetic links between ASDs and typical variation in social behavior and adaptive functioning. This finding is evidenced through both LD score correlation and de novo variant analysis, indicating that multiple types of genetic risk for ASDs influence a continuum of behavioral and developmental traits, the severe tail of which can result in diagnosis with an ASD or other neuropsychiatric disorder. A continuum model should inform the design and interpretation of studies of neuropsychiatric disease biology.
From the paper
... Consistent with traditional approaches to psychiatric phenotypes, most genetic studies of ASDs compare cases to controls to identify risk-associated variation. This approach has been highly productive— recent studies have linked common polygenic as well as de novo and inherited rare variation to ASD risk1,2. Common genotyped SNPs are estimated to account for at least 20% of ASD liability1,3,4. Contributing de novo variants are found in 10–20% of cases, but de novo mutations collectively explain less than 5% of overall ASD liability1,5,6.

Almost all genetic risk factors for ASDs can be found in unaffected individuals. For example, most people who carry a 16p11.2 deletion, the most common large mutational risk factor for ASDs, do not meet the criteria for an ASD diagnosis7. Across healthy populations, there is also substantial variability in capacity for social interaction and social communication8. Although such phenotypic variation is well established, the genetic relationship between neuropsychiatric disorders and typical social and behavioral variation remains unclear. From the first published descriptions of ASDs, clinical and epidemiological reports have commonly noted subthreshold traits of autism in the family members of many diagnosed individuals9,10. Twin and family studies have suggested that these similarities are at least in part inherited and also suggest that traits and diagnosis are correlated genetically11–13, but the correlation has yet to be estimated using measured genetic data.

... These data strongly suggest that genetic influences on ASD risk—both inherited and de novo—influence typical variation in the population in social and communication ability. They also link clinically significant problems to impairments that are less likely to be ascertained. The results have major implications for genetic models of neuropsychiatric disorder risk. It is likely that inherited liability for ASDs is reflected in the behavioral traits of some family members of affected individuals. This links genetic and phenotypic burden in an intuitively consistent fashion with complex, continuously distributed polygenic disease risk. For traits such as height, it is simple to conceptualize a model in which tall parents (for example, those with a height 2 s.d. above the mean) are more likely to have a child who is very tall (for example, one with a height 3 s.d. above the mean). Historically, this concept has been more complicated in neuropsychiatric disorders. Despite extensive evi- dence, some have even questioned the role of inheritance given that the parents of individuals with ASDs or schizophrenia rarely carry a diagnosis themselves. These results suggest that familiality should be studied in a manner beyond a count of categorically affected family members and that trait variation in controls can provide insight into the underlying etiology of severe neurodevelopmental and psychiatric disorders. The behavioral influence of de novo and inherited genetic risk for ASDs can be quantified, and studies assessing continuous trait variation are likely better equipped to examine the phenotypic correlates of neuropsychiatric disease risk.

Wednesday, March 23, 2016

Obama: "Don't do stupid sh*t"



Unlike Hillary, but like Donald Trump and George H.W. Bush, Obama is (mostly) a foreign policy realist.
The Atlantic ... Obama, unlike liberal interventionists, is an admirer of the foreign-policy realism of President George H. W. Bush and, in particular, of Bush’s national-security adviser, Brent Scowcroft (“I love that guy,” Obama once told me). Bush and Scowcroft removed Saddam Hussein’s army from Kuwait in 1991, and they deftly managed the disintegration of the Soviet Union; Scowcroft also, on Bush’s behalf, toasted the leaders of China shortly after the slaughter in Tiananmen Square. As Obama was writing his campaign manifesto, The Audacity of Hope, in 2006, Susan Rice, then an informal adviser, felt it necessary to remind him to include at least one line of praise for the foreign policy of President Bill Clinton, to partially balance the praise he showered on Bush and Scowcroft.

At the outset of the Syrian uprising, in early 2011, [Samantha] Power argued that the rebels, drawn from the ranks of ordinary citizens, deserved America’s enthusiastic support. Others noted that the rebels were farmers and doctors and carpenters, comparing these revolutionaries to the men who won America’s war for independence.

Obama flipped this plea on its head. “When you have a professional army,” he once told me, “that is well armed and sponsored by two large states”—Iran and Russia—“who have huge stakes in this, and they are fighting against a farmer, a carpenter, an engineer who started out as protesters and suddenly now see themselves in the midst of a civil conflict …” He paused. “The notion that we could have—in a clean way that didn’t commit U.S. military forces—changed the equation on the ground there was never true.” The message Obama telegraphed in speeches and interviews was clear: He would not end up like the second President Bush—a president who became tragically overextended in the Middle East, whose decisions filled the wards of Walter Reed with grievously wounded soldiers, who was helpless to stop the obliteration of his reputation, even when he recalibrated his policies in his second term. Obama would say privately that the first task of an American president in the post-Bush international arena was “Don’t do stupid shit.”

Obama’s reticence frustrated Power and others on his national-security team who had a preference for action. Hillary Clinton, when she was Obama’s secretary of state, argued for an early and assertive response to Assad’s violence. In 2014, after she left office, Clinton told me that “the failure to help build up a credible fighting force of the people who were the originators of the protests against Assad … left a big vacuum, which the jihadists have now filled.” When The Atlantic published this statement, and also published Clinton’s assessment that “great nations need organizing principles, and ‘Don’t do stupid stuff’ is not an organizing principle,” Obama became “rip-shit angry,” according to one of his senior advisers. The president did not understand how “Don’t do stupid shit” could be considered a controversial slogan. Ben Rhodes recalls that “the questions we were asking in the White House were ‘Who exactly is in the stupid-shit caucus? Who is pro–stupid shit?’ ” The Iraq invasion, Obama believed, should have taught Democratic interventionists like Clinton, who had voted for its authorization, the dangers of doing stupid shit. (Clinton quickly apologized to Obama for her comments, and a Clinton spokesman announced that the two would “hug it out” on Martha’s Vineyard when they crossed paths there later.) ...

... Obama generally believes that the Washington foreign-policy establishment, which he secretly disdains, makes a fetish of “credibility”—particularly the sort of credibility purchased with force. The preservation of credibility, he says, led to Vietnam. Within the White House, Obama would argue that “dropping bombs on someone to prove that you’re willing to drop bombs on someone is just about the worst reason to use force.”

... I asked the president how he thought his foreign policy might be understood by historians. He started by describing for me a four-box grid representing the main schools of American foreign-policy thought. One box he called isolationism, which he dismissed out of hand. “The world is ever-shrinking,” he said. “Withdrawal is untenable.” The other boxes he labeled realism, liberal interventionism, and internationalism. “I suppose you could call me a realist in believing we can’t, at any given moment, relieve all the world’s misery,” he said. “We have to choose where we can make a real impact.” He also noted that he was quite obviously an internationalist, devoted as he is to strengthening multilateral organizations and international norms.

... Those who speak with Obama about jihadist thought say that he possesses a no-illusions understanding of the forces that drive apocalyptic violence among radical Muslims, but he has been careful about articulating that publicly, out of concern that he will exacerbate anti-Muslim xenophobia. He has a tragic realist’s understanding of sin, cowardice, and corruption, and a Hobbesian appreciation of how fear shapes human behavior. And yet he consistently, and with apparent sincerity, professes optimism that the world is bending toward justice. He is, in a way, a Hobbesian optimist.

... Libya proved to him that the Middle East was best avoided. “There is no way we should commit to governing the Middle East and North Africa,” he recently told a former colleague from the Senate. “That would be a basic, fundamental mistake.”

... The president also gets frustrated that terrorism keeps swamping his larger agenda, particularly as it relates to rebalancing America’s global priorities. For years, the “pivot to Asia” has been a paramount priority of his. America’s economic future lies in Asia, he believes, and the challenge posed by China’s rise requires constant attention.

... Obama believes, [Ash] Carter said, that Asia “is the part of the world of greatest consequence to the American future, and that no president can take his eye off of this.”

... One of the most destructive forces in the Middle East, Obama believes, is tribalism—a force no president can neutralize. Tribalism, made manifest in the reversion to sect, creed, clan, and village by the desperate citizens of failing states, is the source of much of the Muslim Middle East’s problems, and it is another source of his fatalism. Obama has deep respect for the destructive resilience of tribalism—part of his memoir, Dreams From My Father, concerns the way in which tribalism in post-colonial Kenya helped ruin his father’s life—which goes some distance in explaining why he is so fastidious about avoiding entanglements in tribal conflicts.

“It is literally in my DNA to be suspicious of tribalism,” he told me. “I understand the tribal impulse, and acknowledge the power of tribal division. I’ve been navigating tribal divisions my whole life. In the end, it’s the source of a lot of destructive acts.”

... “The fact is that Ukraine, which is a non-nato country, is going to be vulnerable to military domination by Russia no matter what we do,” he said.

I asked Obama whether his position on Ukraine was realistic or fatalistic.

“It’s realistic,” he said. “But this is an example of where we have to be very clear about what our core interests are and what we are willing to go to war for. And at the end of the day, there’s always going to be some ambiguity.”

... Obama has come to a number of dovetailing conclusions about the world, and about America’s role in it. The first is that the Middle East is no longer terribly important to American interests. The second is that even if the Middle East were surpassingly important, there would still be little an American president could do to make it a better place. The third is that the innate American desire to fix the sorts of problems that manifest themselves most drastically in the Middle East inevitably leads to warfare, to the deaths of U.S. soldiers, and to the eventual hemorrhaging of U.S. credibility and power. The fourth is that the world cannot afford to see the diminishment of U.S. power.
See also The One Sided Clash of Civilizations.

Saturday, March 19, 2016

Dialog 2016


Everything at this meeting is off the record, so I can't say much about it. The one comment I'll make is that among this group of elites almost no one I've spoken to groks Trump or his appeal to a large number of Americans.
Dialog is an biannual 2-day thought retreat, gathering 150 global leaders to discuss how to change the world. Dialog was created in 2006 to bring together global leaders across industries to discuss some of the most pressing world issues, to provide an opportunity for cross-pollination & collaboration.

There are no speakers. No panels. All attendees participate in break-out facilitated discussions. And we limit the discussion to only 150 global leaders who can have an impact now and emerging leaders who can help implement the plans we develop.

There are no speeches, just many coordinated, moderated break-out discussions of 6-15 people. The agenda is determined by the attendees directly, based on their interests and needs.

Dialog is an invite-only retreat and we carefully curate all participants. Dialog is 100% off-the-record and not-for-attribution. Dialog is hosted by Auren Hoffman and Peter Thiel.

Tuesday, March 15, 2016

Geoff Hinton on Deep Learning

This is a recent, and fairly non-technical, introduction to Deep Learning by Geoff Hinton.



In the most interesting part of the talk (@25 min; see arxiv:1409.3215 and arxiv:1506.00019) he describes extracting "thought vectors" or semantic (meaning) relationships from plain text. This involves a deep net, human text, and resulting vectors of weights.

The slide below summarizes some history. Most of the theoretical ideas behind Deep Learning have been around for a long time. Hinton sometimes characterizes the advances as resulting from a factor of a million in hardware capability (increase in compute power and data availability), and an order of magnitude from new tricks. See also Moore's Law and AI.

Monday, March 14, 2016

Demis Hassabis: The Future of Artificial Intelligence

Thanks to AlphaGo and Lee Sedol, even my wife is interested in AI :-)

Here's a recent talk by DeepMind CEO Demis Hassabis, whose comments start @5:30 min. The content of this talk is suitable for a non-technical audience.



@39 min: AlphaGo value / policy nets, and tree search.

@1h03: over the summer DeepMind will look at the internal representations used in the valuation engine to see how they correspond to expert human intuitions about Go. This is like peeking into the mind of an alien creature that evolved fighting for territory in a 2D world with discrete spacetime :-)

Here's a related comment that appeared on a HNN thread about the Lee Sedol match:
As someone who studied AI in college and am a reasonably good amateur player, I have been following the matches between Lee and AlphaGo.

AlphaGo plays some unusual moves that go clearly against any classically trained Go players. Moves that simply don't quite fit into the current theories of Go playing, and the world's top players are struggling to explain what's the purpose/strategy behind them.

I've been giving it some thought. When I was learning to play Go as a teenager in China, I followed a fairly standard, classical learning path. First I learned the rules, then progressively I learn the more abstract theories and tactics. Many of these theories, as I see them now, draw analogies from the physical world, and are used as tools to hide the underlying complexity (chunking), and enable the players to think at a higher level.

For example, we're taught of considering connected stones as one unit, and give this one unit attributes like dead, alive, strong, weak, projecting influence in the surrounding areas. In other words, much like a standalone army unit.

These abstractions all made a lot of sense, and feels natural, and certainly helps game play -- no player can consider the dozens (sometimes over 100) stones all as individuals and come up with a coherent game play. Chunking is such a natural and useful way of thinking.

But watching AlphaGo, I am not sure that's how it thinks of the game. Maybe it simply doesn't do chunking at all, or maybe it does chunking its own way, not influenced by the physical world as we humans invariably do. AlphaGo's moves are sometimes strange, and couldn't be explained by the way humans chunk the game.

It's both exciting and eerie. It's like another intelligent species opening up a new way of looking at the world (at least for this very specific domain). and much to our surprise, it's a new way that's more powerful than ours.
Note AlphaGo almost certainly uses chunking of some sort ("feature identification" in the neural net terminology), but perhaps not the kind familiar to our brains, which evolved in the physical/biological world.

@1h04: No surprise, Hassabis seems to believe in strong AI.

See also

Moore's Law and AI
DeepMind and Demis Hassabis
Deep Neural Nets and Go: AlphaGo beats European champion.

Saturday, March 12, 2016

Steven Pinker, Stephen Hsu and Dalton Conley: Can Genius Be Genetically Engineered?



This is the video from our 92Y event on Thursday. Kudos to Jamie Metzl and the 92Y team for an excellent event!

Thanks to all the readers of this blog who showed up to listen :-)

If you like this video, you may also like this earlier discussion at the Helix Center: Understanding Genius.

Wednesday, March 09, 2016

Can Genius Be Genetically Engineered?


See you at the 92nd Street Y tomorrow (Thu, Mar 10, 2016, 8:15 pm)!
With rapid advances in genome sequencing, genetic analysis and precision gene editing, it’s becoming ever more likely that embryo selection and genetic engineering could be used to optimize the intelligence of our future children.

Although the complexities of genetics, the brain and human experience will make maximizing human intelligence far more complicated than it may now seem to some, genetic brain optimization and enhancement could very well be a driver of our future evolution as a species. Jamie Metzl moderates Steven Pinker, Professor of Psychology at Harvard University, and Stephen Hsu, Professor of Theoretical Physics at Michigan State University, experts from the worlds of science and biotech, in a discussion of the practical, scientific, philosophical and ethical issues associated with engineering intelligence.
The event will be video recorded, and possibly live streamed, see below:
92Y OnDemand/Livestream: As we do with many of our events, we would love to have our event live streamed directly onto our on demand website. We also have another great opportunity with a new partnership and we will live stream on the MSNBC website as well. With your approval, we will coordinate the details on our end. I have attached our standard release to this email should you be able to sign and return in advance, if not, it can signed upon arrival.

Tuesday, March 08, 2016

Mapping the Future of Virtual Reality

This is a good discussion of VR technology, on the Andreesen Horowitz podcast. I recently bumped into a tech founder who swears the transition to full immersion is real and right around the corner technologically.
a16z Podcast: Mapping the Future of Virtual Reality

Virtual reality is coming fast, and everyone seems to assume that it will be gamers who get to have all the fun first. But there are other applications for VR that could also bring it into the mainstream. “It could very well be business users,” says 16z’s Chris Dixon. “It’s anything where you would want time travel or teleportation.”

Dixon is joined on this segment of the podcast by Saku Panditharatne and Kyle Russell, both on the firm’s deal team, to offer their perspective on how virtual reality is likely to enter all of our lives. This year promises to be the moment when more than a very small number of people will get their first taste of VR. What that looks and feels like, and what that shared experience sets in motion on this segment of the a16z podcast.

One funeral at a time?


A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it. -- Max Planck
I'm at the annual AAU meeting of research Vice-Presidents, and the "reproducibility crisis" (in some fields) is one of the topics on the agenda. Today I heard a nice talk by Brian Nosek on the Reproducibility Project and Open Science Framework. Afterwards I asked him whether other social psychologists were really absorbing the implications of the low reproducibility rate in their field. Nosek said that attitudes were changing rapidly and that in 10 years the field would be very different. If so, progress can happen much faster than in Max Planck's pessimistic quote. Let's hope Nosek is right!

As an example of soul searching (learning can hurt!) Nosek pointed me to this blog post, by Professor Michael Inzlicht of Toronto. To his credit, Inzlicht is taking seriously the replication difficulties of two effects he has worked on in the past: ego depletion (i.e., willpower fatigue) and stereotype threat. Anyone who has looked carefully at the literature (positive effects from small sample sizes, but failed replication or very small effect size results from much larger samples) has to question whether these much-hyped phenomena are real. There is also lots of evidence for publication bias.
Inzlicht: ... I have spent nearly a decade working on the concept of ego depletion, including work that is critical of the model used to explain the phenomenon. I have been rewarded for this work, and I am convinced that the main reason I get any invitations to speak at colloquia and brown-bags these days is because of this work. The problem is that ego depletion might not even be a thing. By now, many people are aware that a massive replication attempt of the basic ego depletion effect involving over 2,000 participants found nothing, nada, zip. Only three of the 24 participating labs found a significant effect, but even then, one of these found a significant result in the wrong direction!

There is a lot more to this registered replication than the main headline, and deep in my heart, it is hard to believe that fatigue is not a real phenomenon. I promise to get to it in a later post. But for now, we are left with a sobering question: If a large sample pre-registered study found absolutely nothing, how has the ego depletion effect been replicated and extended hundreds and hundreds of times? More sobering still: What other phenomena, which we now consider obviously real and true, will be revealed to be just as fragile?

As I said, I’m in a dark place. I feel like the ground is moving from underneath me and I no longer know what is real and what is not.

I edited an entire book on stereotype threat, I have signed my name to an amicus brief to the Supreme Court of the United States citing stereotype threat, yet now I am not as certain as I once was about the robustness of the effect. I feel like a traitor for having just written that; like, I’ve disrespected my parents, a no no according to Commandment number 5. But, a meta-analysis published just last year suggests that stereotype threat, at least for some populations and under some conditions, might not be so robust after all. P-curving some of the original papers is also not comforting. Now, stereotype threat is a politically charged topic and I really really want it to be real. I think a lot more pain-staking work needs to be done before I stop believing (and rumor has it that another RRR of stereotype threat is in the works), but I would be lying if I said that doubts have not crept in. ...
See also Is science self-correcting? Figure at top is from this meta-analysis of stereotype threat.

Thursday, March 03, 2016

Jiujitsu: Kinetic Chess

These videos are from Roy Dean's BJJ academy in Bend, Oregon. In the first video Dean narrates each 5 minute match (shown first in slow motion, then at full speed), explaining the techniques, strategy, and mechanics of high level grappling. The competitors vary in style, skill level, and size (from ~160 to 220 lbs). The matches are what I would characterize as old-school (position --> submission) BJJ, not the boring win-on-advantage style that has become common in tournaments.

In the second video Dean pushes the action more aggressively, giving up a bit of the sparring "flow" found in the first.





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