I am not sure if this warrants its own answer, but I suspect you are calling them
This is because
The name and the property might not be related too directly because arguably the name is much easier to spot than the property, and should thus not give away too much of the actual puzzle.
The connection might be via
Firstly, the categorisation
Given that information it seems that the numbers of Y are unvalued because
R. Why are the numbers of row Z unvalued?
S. What are the first and last numbers of each row other than row Y?
T. What is the smallest positive number in row Y?
U. How long is the longest sequence of consecutive numbers in any row other than row Y?