Hufflepuff
I went to a school with a house system. The houses were given attributes that now seem very familiar from Harry Potter.
We had a brainy Ravenclaw-equivalent, and a rather foolish bumbling Hufflepuff-equivalent (nobody wanted to be in the Hufflepuff-equivalent!) and two other houses. With the benefit of hindsight, I can now see that both of the remaining two houses *thought* that they were the Griffindor-equivalent, and considered the other one to be the Slytherin-equivalent.
The similarities were clear enough that when I first read Harry Potter I actually wondered if Rowling at been at my school, but no. So now I suspect these characteristics of being widespread among school houses, at least in the 1980s.