Science and Technology links (November 12 2023)

  1. Vitamin K2 supplements might reduce the risk of myocardial infarction (heart attacks) and of all-cause death (Hasific et al. 2022). You find vitamin K2 in some Gouda cheeses and in eggs.
  2. Most of the water on Earth is salinated (in the oceans) and cannot be consumed. Fresh water is often scarce. Yet Israel is desalinating water for less than a dollar per cubic meter.
  3. People living in South America engaged in warfare for 10,000 years before the arrival of the Europeans (Standen et al. 2023).
  4. The last glacial period ended about 12,000 years ago and lasted about 100,000 years. About 26,000 years ago, all of Canada was covered by a permanent ice sheet. Thus many of us were taught in school that human beings first colonized America about 12,000 years ago by the Bering land bridge, that existed back then between modern-day Russia and modern-day Alaska. The evidence accumulates that there were human beings in America much earlier than initially thougth. They would have been present 21,000 to 23,000 years ago in New Mexico. We even have their footprints.
  5. As recently as 20,000 years ago—not long in geological terms—Britain was not, in fact, an island. Instead, the terrain that became the British Isles was linked to mainland Europe by Doggerland, a tract of now-submerged territory where early Mesolithic hunter-gatherers lived, settled and traveled (McGreevy, 2020). Correspondly, there were human beings in Ireland 31,000 years ago.
  6. Gray et al. (2023) argue that the limited freedom that children enjoy in our modern societies is leading to a rise in mental disorders.
  7. Most people cannot understand the bat and ball problem, even after the solution is given. The problem can be stated as follows: “A bat and a ball cost $1.10 in total. The bat costs $1.00 more than the ball. How much does the ball cost?” ChatGPT can solve it:
  8. When hiring, we find a slight bias in favour of females in male-dominated fields, and a strong bias in favour of females in female-dominated fields (Schaerer et al., 2023). Overall, people greatly overestimate gender biases in hiring.
  9. Retinol, a common cosmetic product, keeps one’s skin younger.
  10. Unwarranted financial optimism might be the result of low cognitive abilities.

Published by

Daniel Lemire

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

3 thoughts on “Science and Technology links (November 12 2023)”

  1. How often is the bat and ball problem in chatGPTs training data?
    I’d still argue that it can reproduce the solution it learned, not actually solve it.

    1. Indeed. DuckDuckGoing for “Bat and Ball Problem” gives several hits with the precise formulation noted here. Curious whether it would respond correctly if you replaced “Bat and Ball” with “Keyboard and Mouse”, and “$1.10 and $1.00 dollars” with “$50 and $10”, or some other arbitrary formulation?

      Nevertheless, ChatGPTs knowledge of obscure math problems is interesting, though not particularly indicative of its intelligence (similar to some people I encountered at university.)

  2. I don’t know how grade school arithmetic is taught in other parts of the world. But in China, students are trained to pay extreme attention to “off by 1” problems. Fencepost problems are standard questions in exams (“Trees are planted along a 100-meter street from the beginning to the end with a 5-meter spacing, how many trees are there?”). Furthermore, when proportions and fractions are taught, the difference between “a 2x speed / 2x as fast” vs. “2x faster” is always strictly distinguished. In the former case, it means a ratio of 2:1, and the latter case, it means a ratio of 3:1 (the “200%” applies just to the difference – the “-er” part only). Misreading one word in the question and you get 0 point. As a result, most people have been conditioned to always prefer saying “quantity A is x times quantity B” rather than “quantity A is x times higher than quantity B”.

    Both terms are rarely distinguished in many languages. In English they’re more or less interchangeably used in a loose manner, even by engineers. Thus, many people would probably agree with the criticism that such teaching is merely “punishing students for irrelevant matter in semantics details”. Nevertheless, the teaching is probably also appreciated by everyone who later started doing computer programming.

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