Science and Technology links (December 22nd, 2017)

Bitcoins are electronic records that are meant to be used as currency. They have become increasingly popular and expensive. Reportedly, the famous investment bank Goldman Sachs is planning to offer bitcoin financial services in the summer of 2018.

Doing away with television and switching to subscription services like Netflix reduces your exposure to ads. So we have Facebook and Google who earn almost all their money through ads. Netflix is effectively saving us from ads.

MagicLeap, the Florida-based augmented reality company, has announced its first product… some good looking glasses. Apparently, they are quite nice. Price remains undisclosed and you cannot buy them in store yet. It appears that will need to strap on some computer to make them work.

People are typically very interested in fairness, though it is sometimes unclear what it means in practice. What if you recruited your employees based on anonymized resumes where you can’t tell the race or the gender of the candidate? That would be “fairer” certainly, right? Maybe not:

We find that participating firms become less likely to interview and hire minority candidates when receiving anonymous résumés. We show how these unexpected results can be explained (…) by the fact that anonymization prevents the attenuation of negative signals when the candidate belongs to a minority.

It is widely believed that there is more genetic variation within human populations than between them. On this basis, it follows that the concept of “human race” is likely “socially constructed”: it has no biological basis. West Hunter has a counterpoint:

Pygmies couldn’t really be hugely shorter than most other human populations. Yet they are short (five or six standard deviations shorter)

He also points out that evolution can run its course faster than we might intuitively expect. For example, lactose tolerance is thought to have evolved in the last 10,000 years or so. Thus while it is impossible to have a rational discussion about it in today’s political climate, there are significant genetic differences between human populations, that is simply a scientific fact. It does not follow that the concept of human race is useful or relevant, but if we were a scientific civilization, we would certainly be able to talk openly about genetic differences between populations.

Awni Hannun has a post entitled Speech Recognition Is Not Solved. It is a response to same claims made this year that computers have no better speech recognition than human beings (Microsoft made such claims). He points out that performance is a major constraint when deploying new algorithms…

(Latency) Bidirectional recurrent layers are a good example of a latency killing improvement. All the recent state-of-the-art results in conversational speech use them. The problem is we can’t compute anything after the first bidirectional layer until the user is done speaking. So the latency scales with the length of the utterance.

(Compute) The amount of computational power needed to transcribe an utterance is an economic constraint. We have to consider the bang-for-buck of every accuracy improvement to a speech recognizer. If an improvement doesn’t meet an economical threshold, then it can’t be deployed.

To a lot engineers, this will sound quite familiar. Research papers often rely on trade-offs that are simply unrealistic in the real world.

Published by

Daniel Lemire

A computer science professor at the University of Quebec (TELUQ).

8 thoughts on “Science and Technology links (December 22nd, 2017)”

  1. There is plenty of scientific discussion on the genetic origins of various human populations and the genetic differences between them. It also makes the news quite often, as people are interested in knowing where they come from.

    Human populations tend to migrate and mix too frequently to form distinct subspecies (or “races”). We end up with a continuum of populations, and even distant populations are often genetically close. We can still observe something resembling breeds: populations that have been selected for various traits but that are otherwise genetically similar to each other.

    1. “We end up with a continuum of populations”

      Like the continuum of colors?

      “distant populations are often genetically close”

      Like England and Australia?

      “Human populations tend to migrate and mix too frequently to form distinct subspecies”

      Pygmies are not a subspecies?

      1. If there is a continuum of populations with frequent gene flow between them, there are no subspecies. That’s the way biologists have defined their terminology.

        Europeans and Aboriginal Australians are at opposite ends of the continuum. Both groups are believed to descend from the same relatively small populations that migrated out of Africa around 70000 years ago. Aboriginal Australians were separated from the rest of humanity long enough that they might have formed a subspecies at one point. Because of the recent population bottleneck, they were still genetically close to Eurasians and Native Americans. Of course, that separation no longer exists due to the high intermarriage rates between Aboriginal Australians and recent immigrants.

        The pygmy phenotype is believed to be a genetic adaptation to hunter-gatherer life in tropical rainforests. It has developed independently in Africa, Southeast Asia, and South America. There is also evidence that suggests that multiple populations have developed the phenotype independently on each continent. Because pygmy populations frequently mix with neighboring non-pygmy populations, they cannot be considered subspecies.

        1. “Because pygmy populations frequently mix with neighboring non-pygmy populations, they cannot be considered subspecies.”

          How do they stay short if they mix?

          “If there is a continuum of populations with frequent gene flow between them, there are no subspecies”

          Indian castes?

          1. As long as the selective pressure exists, the population can sustain a certain degree of incoming gene flow without changes in phenotype distribution. Pygmies remain short for the same reason as native Europeans still have light skin, despite millennia of migrations from the Eurasian Steppe, Middle East, and North Africa.

            The Indian caste system is a nice natural experiment in genetic differentiation. However, it has only lasted for around 70 generations, which is a short time in evolution. For a comparison, many dog breeds have been separated for hundreds of even thousands of generations, but they still belong to the same subspecies of the gray wolf.

  2. Fst ( a measure of genetic differentiation) between Europeans and West Africans is 0.153.

    Fst between timber wolves and coyotes: 0.153

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