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Big-O notation and real-world performance
From Daniel Lemire's Blog

Big-O notation and real-world performance

Classical Newtonian mechanics is always mathematically consistent. However, Newtonian mechanics assumes that bodies move without friction and that we stay far from...

Should computer scientists run experiments?
From Daniel Lemire's Blog

Should computer scientists run experiments?

Jeffrey Ullman, a famous computer science professor, published an essay pushing back about the need to run experiments in computer science. Apparently, some conference...

Fast integer compression in Java
From Daniel Lemire's Blog

Fast integer compression in Java

Last year, we published a fast C++ library to quickly compress and decompress arrays of integers. Out of habit, I ported it to Java and published it under the name...

Staying sharp requires “intellectual gardening”
From Daniel Lemire's Blog

Staying sharp requires “intellectual gardening”

Gardening requires consistency. A beautiful garden is unstable. Some plants want to expand their reach and kill out the competition. Some plants are simply out...

Hashing and the Birthday paradox: a cautionary tale
From Daniel Lemire's Blog

Hashing and the Birthday paradox: a cautionary tale

If you meet a stranger, the probability that he will have the same birth date as yourself is probably less than 1%. It is roughly 1/365 if you make simplifying...

Meetings are like sex
From Daniel Lemire's Blog

Meetings are like sex

Meetings are like sex. Everybody thinks that they are good at it… until they ask for the truth. We never have real discussions about it: I did not want to say anything…...

Why I never give straight answers
From Daniel Lemire's Blog

Why I never give straight answers

There are some questions that you should never answer. This is true when you are facing justice, your angry wife, or students. Carl Zimmer, a famous science writer...

Three questions about e-learning in college
From Daniel Lemire's Blog

Three questions about e-learning in college

Timothy Taylor observes that research about online instruction tells us that online teaching is just as effective as classroom teaching. The main drawback of asynchronous...

Crash course in modern economics
From Daniel Lemire's Blog

Crash course in modern economics

I sometimes find it difficult to understand the financial news. So I have written down some notes to help me understand commonly used terms: Austerity: When a government...

A criticism of computer science: models or modèles?
From Daniel Lemire's Blog

A criticism of computer science: models or modèles?

I was recently on a review committee for a PhD proposal. The student was brilliant. His proposal sounded deep and engaging. The methodology looked scientific: build...

How to be effective at open source: by programmers, for programmers
From Daniel Lemire's Blog

How to be effective at open source: by programmers, for programmers

Though it does not get much press, one of the great social and technological innovation of the last 30 years has been open source software. To about 90% of the...

P equal to NP and all that
From Daniel Lemire's Blog

P equal to NP and all that

One of the better known problems in Computer Science is the P versus NP problem. It is often related to the following question: do all problems for which we can...

You probably shouldn’t use a spreadsheet for important work
From Daniel Lemire's Blog

You probably shouldn’t use a spreadsheet for important work

Following the Reinhart-Rogoff case, where famous scientists go formulas wrong in the Excel spreadsheet that supported their research, a lot of people commented...

Share your software early: the Reinhart-Rogoff case
From Daniel Lemire's Blog

Share your software early: the Reinhart-Rogoff case

I like stories where prestigious professors screw up spectacularly. It reminds us that everybody gets it wrong some of the time. The Reinhart-Rogoff story is one...

The irony of “we are the 99 percent”
From Daniel Lemire's Blog

The irony of “we are the 99 percent”

David Graeber is credited (by himself) as the true organizer of the Occupy Wall Street movement, a widely reported month-long demonstration against capitalism....

Do we lose intelligence and creativity as we grow older?
From Daniel Lemire's Blog

Do we lose intelligence and creativity as we grow older?

It was popular during the XXth century to say that most scientific discovery are done by young scientists (under 30). The implicit assumption was that the brain...

The 2013 Data 2.0 Summit
From Daniel Lemire's Blog

The 2013 Data 2.0 Summit

The Data 2.0 Summit will be held in San Francisco at the end of the month (April 30th 2013). Some of the speakers might interest the readers of this blog. For example...

We are  sentenced to permanent cognitive stretching
From Daniel Lemire's Blog

We are sentenced to permanent cognitive stretching

If you want to get better at something, should remain in your comfort zone? Or should you, rather, be exposed to ideas or techniques slightly beyond your reach?...

We need to get a lot better at imagining the future
From Daniel Lemire's Blog

We need to get a lot better at imagining the future

We live in an era of fast changes. Ten years ago, YouTube was unthinkable, social media did not exist (Facebook was founded in 2004), we got our movies on tapes...

Advanced tips for dealing with your email inbox
From Daniel Lemire's Blog

Advanced tips for dealing with your email inbox

I probably receive 50 emails a day, not counting spam. Give it a week, and I could easily end up with 200 unread emails in my inbox. When that happens, it feels...
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