Map of the results of PISA (Programme for International Student Assessment) in science, reading, and mathematics in Europe
Results of the PISA 2015 (Programme for International Student Assessment) in science, reading, and mathematics visualized on a map of Europe. (...)

The ‘day of the week boy or girl’ paradox explained
There is a wellknown result in probability theory that seems to defy common sense. Note that in the problem statement we assume that the (...)
July 25, 2016 – Jakub Marian – Mathematics

Labelling articles as “per capita” when the unit used is different
After I published my recent article about the Number of metal bands per capita in Europe, I got quite a few comments saying that my use of (...)
May 29, 2016 – Jakub Marian – Mathematics

What does it mean for a function to be welldefined?
A common addendum to a formula defining a function in mathematical texts is, “it remains to be shown that the function is well defined.” (...)
March 3, 2015 – Jakub Marian – Mathematics

Are statistical data and scientific results subject to copyright?
I have recently created a map showing the number of books published per year per capita by country in Europe. The figures in the map are (...)
February 4, 2015 – Jakub Marian – Biology, Blog, Chemistry, Cognition, Mathematics, Nutrition, Physics

Is 0.999… (repeating) equal to 1?
The short answer is yes. $0.\bar 9$ (zero point 9 repeating) is exactly 1. However, a lot of people find this result counterintuitive (...)
October 16, 2014 – Jakub Marian – Mathematics

Do certain numbers in a lottery have a higher probability of winning than others?
Does going for “nice” sequences of numbers, like 1 2 3 4 5 6, reduce the probability of winning in a lottery? Some people think so. “Have (...)
September 25, 2014 – Jakub Marian – Mathematics

Will computers ever be smarter than humans?
When I was a child, I was fascinated by the idea that some day we will be able to construct computers that will be smarter than us. Later, (...)
September 12, 2014 – Jakub Marian – Mathematics

Arithmetics in which you can divide by zero
When I was still in primary school, I was fascinated by things you “can’t do” in mathematics and developed a “theory” of division by zero. (...)
June 8, 2014 – Jakub Marian – Mathematics

Is it possible to divide by zero?
This is a common question on mathematical discussion boards, with people sometimes feeling that mathematicians are too closedminded for (...)
June 7, 2014 – Jakub Marian – Mathematics
