What does a negative Clash of Code ranking score mean?

If you look at the Clash of Code leaderboard and then sort by “Score: Increasing order” there are thousands of people with a negative Clash of Code score.

What does this mean? How is that score calculated?

The scoring system is calculated based on your rank and the rank of those around you. So, let us consider the hypothetical situation where all the guys in the bottom join the clash, one of them will lose, and this will impact his ranking as those around him are at the same level.

So, he will get a -0. something as his score. This will cause his net score to be negative.

This is a rare case, but you get the idea :).

I see. Is there a specific algorithm being used, or do you have the name of that algorithm?

Yes, it is a widely used algorithm known as “TrueSkill”
https://trueskill.org/