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Is there a common method for detecting the convergence of the Gibbs sampler and the expectation-maximization algorithm? - Quora
In practice and theory it is much easier to diagnose convergence in EM (vanilla or variational) than in any MCMC algorithm (including Gibbs sampling).
There is a special case when you can actually obtain the stationary distribution, and be sure that you did! If your markov chain consists of a discrete state space, then take the first time that a state repeats in your chain: if you randomly sample an element between the repeating states (but only including one of the endpoints) you will have a sample from your true distribution.

One can achieve this 'exact MCMC sampling' more generally by using the coupling from the past algorithm (Coupling from the past).

Otherwise, there is no rigorous statistical test for convergence. It may be possible to obtain a theoretical bound for the convergence rates: but these are quite difficult to obtain, and quite often too large to be of practical use. For example, even for the simple case of using the Metropolis algorithm for sampling from a two-dimensional uniform distribution, the best convergence rate upper bound achieved, by Persi Diaconis, was something with an astronomical constant factor like 10^300.

In fact, it is fair to say that for most high dimensional problems, we have really no idea whether Gibbs sampling ever comes close to converging, but the best we can do is use some simple diagnostics to detect the most obvious failures.
nibble  q-n-a  qra  acm  stats  probability  limits  convergence  distribution  sampling  markov  monte-carlo  ML-MAP-E  checking  equilibrium  stylized-facts  gelman  levers  mixing  empirical  plots  manifolds  multi  fixed-point  iteration-recursion  heuristic  expert-experience  theory-practice  project 
13 days ago by nhaliday
What the ctenophore says about the evolution of intelligence | Aeon Essays
The ctenophore’s brain suggests that, if evolution began again, intelligence would re-emerge because nature repeats itself
ocean  biology  brain  evolution  convergence  life  ctenophore 
4 weeks ago by xer0x
How Your Brain Is Like the Cosmic Web
The total number of neurons in the human brain falls in the same ballpark of the number of galaxies in the observable universe.
. . .
The eye immediately grasps some similarity between images of the cosmic web and the brain. ...
Is the apparent similarity just the human tendency to perceive meaningful patterns in random data (apophenia)? Remarkably enough, the answer seems to be no: Statistical analysis shows these systems do indeed present quantitative similarities.

-- Peter Brown
Nautilus | | jul 2017, jul 2019
convergence  science  format-article  type-information 
11 weeks ago by tometaxu
"Une organisation a besoin de ET de " comme le souligne .
Au point qu'il recomm…
convergence  divergence  from twitter_favs
may 2019 by sfermigier
Cap & Share | Simple, fair, and it gets us there
Climate Action. But what action? Cap and Share is the answer
convergence  carbon.budget  carbon.pricing  + 
may 2019 by zesteur
Convergence Between Platforms in the Newsroom: An applied study of Al-Jazeera Mubasher: Journalism Practice: Vol 13, No 4
Through ethnographic observation and content analysis, this study aims to classify the Al-Jazeera Mubasher (AJM) newsroom according to the Schantin  model of newsrooms, describe the network’s convergence level based on the Dailey, Demo, and Spillman Dynamic Scale Model, and present a unique model elucidating how, specifically, convergence works at AJM. Based on the Schantin model of newsrooms, AJM can be classified as a second-generation newsroom, a “cross-media platforms newsroom.” Convergence among the different platforms of AJM is considerable, but still below full convergence level. Accordingly, the AJM newsroom can be classified into the fourth level of the Dailey et al. Dynamic Scale Model — “content sharing.” The unique AJM-specific model presented near the end of this paper depicts the ways in which different AJM platforms function and interact inside the newsroom, explains the degree of convergence between platforms, and classifies the newsroom in terms of its convergence level.
convergence  Research  aj 
april 2019 by paulbradshaw
Safety, Diversity & Inclusion at the Top of GM's Firm-Selection Process | Corporate Counsel
Hundreds of law firms had been working with General Motors over the years, according to executive vice president and general counsel Craig Glidden, who said that was far too many. Inspired by CEO Mary Barra’s mission to change how GM does business, he and a team of in-house lawyers found a way to whittle down the number of firms the company uses and make sure those firms reflect GM values.
“I think she has really led a transformation of the company in dealing with the future of mobility, whether that be dealing with electric vehicles or autonomous vehicles,” Glidden said of Barra during an interview on Tuesday.

Glidden said as much as the legal department wanted good business partners,
convergence  client 
march 2019 by JordanFurlong
Outside Law Firm Panel Convergence – Innovation Driver or Innovation Destroyer? | DennisKennedy.Blog
Stories abound these days about general counsels wanting their outside law firms to help them with innovation and technology efforts. My own conversations indicate that the real wish goes a step further. General counsel want their outside firms to bring them measurable value with innovation and technology initiatives that align with their legal and, more importantly, business goals. Even a quick scan of a recent survey results from Thompson Hine will have you agreeing with their assessment that there is an “Innovation Gap.” Only 29% of participants said that their outside firms have brought them “significant” innovation.
convergence  clients  firms  innovation 
february 2019 by JordanFurlong
Looking back on Convergence Culture – creativity/machine
Convergence is a dynamic of change. In the most neutral and general sense, it describes the tendency for separate streams or pathways (whether of matter, of technologies, or of biological life) to come together. Its complement is divergence — the tendency for these same paths and streams to branch, fork, and drift apart.

In the context of media and communication, convergence is the tendency of separate media technologies, cultural forms, and/or social practices to come together to perform similar functions and make new hybrid media systems. In this sense, it is a key driver of economic, technological, and cultural change in the media environment. Convergence, then, is one of the constitutive dynamics of new media (Hartley, Burgess, & Bruns, 2013).

From the late 1990s through the mid 2000s, the concept of media convergence was especially prominent. It featured in media scholarship, in popular reporting about the internet and digital media, and in media policy circles. There is even a well-respected academic journal that took its title from the concept and the dynamics of media change it represents: the title Convergence: The International Journal of New Media Technologies implicitly suggests that “convergence” is the primary dynamic of new media.

During this peak in the 2000s, the concept was strongly associated with a certain optimistic vision of participatory culture — springing especially from the fact that audiences and fans were now talking about, evaluating, curating, and remixing media content via the same digital networks that media producers were using to distribute and market it. Henry Jenkins is most famously associated with this model of media convergence, and he elaborated the concept in his influential and much-debated book Convergence Culture: Where Old and New Media Collide (2006).

However , other scholars have raised concerns about Jenkins’ approach to convergence — so much so that an entire special issue of the journal Cultural Studies was given over to scholarly critiques of the “overuse” and conceptual limitations of the term, some of which are directed at Jenkins specifically but also at “participatory culture” approaches more generally (see Hay & Couldry, 2011, for an overview). Across the twelve contributions to the collection, the recurring themes concern a perceived lack of attention to history and power — in particular, because of its focus on the ‘newness’ of new media, the contributors suggest that work on convergence and participatory culture in digital media suffers in comparison to the power of a “conjunctural analysis” of the kind associated with (British) Cultural Studies; as well as exhibiting a lack of understanding of the socially and environmentally destructive impacts of technological and economic convergence.
january 2019 by s218611
MARTECHSERIES – Majesco Announces Brian Solis As A Keynote Speaker At Convergence 2019
MarTechSeries Announcment: Convergence 2019 – Brian Solis to be Keynote Speaker.

Excerpt: Majesco, a global provider of market-leading insurance technology announced that Brian Solis will be a keynote speaker at its upcoming customer conference Convergence 2019 taking place in Savannah, Georgia on April 14 – 17, 2019.
brian+solis  convergence  convergence2019  keynote  Speaking  brian  solis 
january 2019 by briansolis

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