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Science and Technology links (December 15th 2018)
From Daniel Lemire's Blog

Science and Technology links (December 15th 2018)

Academic excellence is not a strong predictor of career excellence. There is weak correlation between grades and job performance. Grant reviews the evidence inContinue...

Science and Technology links (December 8th 2018)
From Daniel Lemire's Blog

Science and Technology links (December 8th 2018)

The energy density of lithium-ion batteries doubled between 1995 and 2005 but only increased by about 15% between 2005 and 2015. It is estimated that there is relatively...

Asking the right question is more important than getting the right answer
From Daniel Lemire's Blog

Asking the right question is more important than getting the right answer

Schools train us to provide the right answers to predefined questions. Yet anyone with experience from the real world knows that, more often than not, the difficult...

Science and Technology links (December 1st 2018)
From Daniel Lemire's Blog

Science and Technology links (December 1st 2018)

Autism affects about 1% of the population and four times as many males as females. In older highly educated people, drinking 2 cups of coffee a day is associated...

Quickly sampling from two arrays (C++ edition)
From Daniel Lemire's Blog

Quickly sampling from two arrays (C++ edition)

Suppose that you are given two arrays. Maybe you have a list of cities from the USA and a list of cities from Europe. You want to generate a new list which mixes...

Science and Technology links (November 24th 2018)
From Daniel Lemire's Blog

Science and Technology links (November 24th 2018)

There is no association between birth order and personality traits: The results of both within- and between-family research designs revealed no consistent evidence...

Science and Technology links (November 18th 2018)
From Daniel Lemire's Blog

Science and Technology links (November 18th 2018)

It seems that reducing your carbohydrate (sugar) intake might be a good way to lose weight: lowering dietary carbohydrate increased energy expenditure during weight...

Simple table size estimates and 128-bit numbers (Java Edition)
From Daniel Lemire's Blog

Simple table size estimates and 128-bit numbers (Java Edition)

Suppose that you are given a table. You know the number of rows, as well as how many distinct value each column has. For example, you know that there are two genders...

Memory-level parallelism: Intel Skylake versus Apple A12/A12X
From Daniel Lemire's Blog

Memory-level parallelism: Intel Skylake versus Apple A12/A12X

Modern processors execute instructions in parallel in many different ways: multi-core parallelism is just one of them. In particular, processor cores can have several...

Science and Technology links (November 10th, 2018)
From Daniel Lemire's Blog

Science and Technology links (November 10th, 2018)

It already takes more energy to operate Bitcoin than to mine actual gold. Cryptocurrencies are responsible for millions of tons of CO2 emissions. (Source: Nature)...

Measuring the memory-level parallelism of a system using a small C++ program?
From Daniel Lemire's Blog

Measuring the memory-level parallelism of a system using a small C++ program?

Our processors can issue several memory requests at the same time. In a multicore processor, each core has an upper limit on the number of outstanding memory requests...

Science and Technology links (November 3rd, 2018)
From Daniel Lemire's Blog

Science and Technology links (November 3rd, 2018)

Bitcoin, the cryptocurrency, could greatly accelerate climate change, should it succeed beyond its current speculative state. Crows can solve novel problems very...

Science and Technology links (October 28th, 2018)
From Daniel Lemire's Blog

Science and Technology links (October 28th, 2018)

If you take kids born in the 1980s, who do you think did better, the rich kids or the poor kids? The answer might surprise you: The children from the poorest families...

Is WebAssembly faster than JavaScript?
From Daniel Lemire's Blog

Is WebAssembly faster than JavaScript?

Most programs running on web sites are written in JavaScript. There are still a few Java applets and other plugins hanging around, but they are considered obsolete...

Science and Technology links (October 20th, 2018)
From Daniel Lemire's Blog

Science and Technology links (October 20th, 2018)

Should we stop eating meat to combat climate change? Maybe not. White and Hall worked out what happened if the US stopped using farm animals: The modeled system...

Validating UTF-8 bytes using only 0.45 cycles per byte (AVX edition)
From Daniel Lemire's Blog

Validating UTF-8 bytes using only 0.45 cycles per byte (AVX edition)

When receiving bytes from the network, we often assume that they are unicode strings, encoded using something called UTF-8. Sadly, not all streams of bytes areContinue...

Validating UTF-8 bytes (Java edition)
From Daniel Lemire's Blog

Validating UTF-8 bytes (Java edition)

Strings are just made of bytes. We send and receive bytes over the network all the time. If you know that the bytes you are receiving form a string, then chances...

Nobel-prize winner Rommer on innovation and higher education
From Daniel Lemire's Blog

Nobel-prize winner Rommer on innovation and higher education

Rommer was one of the the winners of the Nobel prize in economics this year (2018). He wrote about higher education and innovation. One of his proposals is theContinue...

Science and Technology links (October 13th, 2018)
From Daniel Lemire's Blog

Science and Technology links (October 13th, 2018)

Chronic exposure to canola oil results in a significant increase in body weight and impairments in working memory… in mice. (Source: Nature) Belly fat is not just...

Smart bracelet: my experience with the Mi Band 3
From Daniel Lemire's Blog

Smart bracelet: my experience with the Mi Band 3

I was an early adopter of fitness bracelets with heart-rate monitoring. I use them to track my heart rate at rest. You heart rate should be around 65 if you are...
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