A long time ago in the minds of many tinkerers, an idea about how everyone has an inherently unique style of typing was born.
You know uniqueness is very hard to prove or produce in Computer Science?
Seems like it’s right there behind our fingertips, and it is not as intrusive and privacy revealing as iris, face, or fingerprint scan.
If you don’t think uniqueness is a big deal just look at Bitcoin addresses implementation. They scaled the whole system to 10^77 which is almost the number of all the atoms in the observable Universe, just to avoid collisions and provide uniqueness to each new address in the network!
What’s so unique with the typing style we all have, you might ask? Same with your handwriting. It’s your brain. There is no need for math to explain this one since it’s conditionally modeled by the physical universe over time with many factors like environment, DNA and habits included. We don’t know how unique our brains exactly are to be able to quantify it. Still, we will take this basic assumption as true and that our styles can be unique enough for the purpose of this experiment, just like styles can be learned to conform to certain criteria through education.
But it’s not just that, the style may vary depending on the keyboard a person might use (mechanical, flat, etc…), a person being sleepy or typing under low light, or even being intoxicated! We will try to take all this into account later when we think about our strategic approach.
Of course, when I came across this same idea I was late to the party as there were already some academic papers explaining how it could be done in theory and discussing different approaches. Later on, I discovered some attempts to verify users’ typing style but with a lot of limitations. We will discuss what those limitations are and how to potentially overcome them.
All datasets in the wild were just big collections of many subjects and attempts recorded in sessions over days. This means there is a lot of data for each subject (over 400). At that time I