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How the “Frontier” Became the Slogan of Uncontrolled AI
Artificial intelligence (AI) has been billed as the next frontier of humanity: the newly available expanse whose exploration …
From Daniel Lemire's Blog
Bit packing is fast, but integer logarithm is slow
In How fast is bit packing?, we saw how to store non-negative integers smaller than 2N using N bits per integer by a technique called bit packing. A careful C++...
From Daniel Lemire's Blog
It is what you do, not what you own
Over 20 years ago, back when I was in high school, I went on a sailboat trip. I was so impressed that I decided to own a sailboat one day. I realized that a sailboat...
From Daniel Lemire's Blog
Publicly available large data sets for database research
Most database research papers use synthetic data sets. That is, they use random-number generators to create their data on the fly. A popular generator is dbgen...
From Daniel Lemire's Blog
Do we need copyright?
The concept of property is a social construction. Animals, such as cats, can own a piece of food, or a territory, but only as long as they are able to personally...
From Daniel Lemire's Blog
From counting citations to measuring usage (help needed!)
We sometimes measure the caliber of a researcher by how many research papers he wrote. This is silly. While there is some correlation between quantity and quality...
From Daniel Lemire's Blog
How fast is bit packing?
Integers values are typically stored using 32 bits. Yet if you are given an array of integers between 0 and 131 072, you could store these numbers using as little...
From Daniel Lemire's Blog
I
I’m an introvert. That’s why you don’t see me at meetings and celebrations. If you do, I’m in a corner looking awkward. That’s why I’m not trying to build a large...
From Daniel Lemire's Blog
What happens when you get more Ph.D.s?
Following the fall of the USSR, hundreds of world class mathematicians emigrated to the USA. Intuitively, this should have made American mathematics stronger. Did...
From Daniel Lemire's Blog
Bitmaps are surprisingly efficient
Imagine you have to copy an array, and update a few values in the process. What is the most efficient way implementation? Let us look at a concrete example. I am...
From Daniel Lemire's Blog
Effective compression using frame-of-reference and delta coding
Most generic compression techniques are based on variations on run-length encoding (RLE) and Lempel-Ziv compression. Compared to these techniques and on the right...
From Daniel Lemire's Blog
Two rules for teaching in the XXIst century
Education in the XXth century has been primarily industrial: organize the workersstudents in groups under the supervision of a managerteacher. We all have been...
From Daniel Lemire's Blog
Citogenesis in science and the importance of real problems
Many papers in Computer Science tell the following story: There is a pre-existing problem P. There are few relatively simple but effective solution to problem P...
From Daniel Lemire's Blog
How to Revise Research Papers After Receiving Harsh Reviews
Whether you submit your work scientific journal or just post it on a blog, you can expect to receive harsh criticism from time to time. Sometimes you are facing...
From Daniel Lemire's Blog
Open access journals in Computer Science
Open access journals make articles freely available. Some of them even allow the authors to keep the copyright of their work. It would seem that they offer a compelling...
From Daniel Lemire's Blog
Should you boycott academic publishers?
There is a growing list of famous scientists who have pledged to boycott Elsevier as a publisher. If I were in charge of Elsevier, I would be very nervous: academic...
From Daniel Lemire's Blog
Use Random Hashing if you Care About Security?
Hashing is a programming technique that maps objects (such as strings) to integers. It is a necessary component of hash tables, one of the most frequently used...
From Daniel Lemire's Blog
Open Science: Why Is It So Hard?
Open access is the idea that scholarship should be accessible to all. Many believe that we should require publicly funded researchers to make their work available...
From Daniel Lemire's Blog
Do we need patents?
Whenever I suggest that patents are harmful, people point to the pharmaceutical industry. The pharmaceutical industry is heavily regulated. Marketing a new drug...
From Daniel Lemire's Blog
Are you a gold prospector, or a construction worker?
Most work is akin to construction jobs: you work until the house is built. You just have to keep the servers running day after day. You keep writing code day after...
From Daniel Lemire's Blog