Mathematics: Data, range and IQR

All types of data within mathematics.

Numerical, Categorical, Numerical Discrete, Numerical Continuous, Categorical Nominal, Categorical Ordinal.

Which data type classifies variables into categories with no logical order (e.g. eye color)?

Data that can be ranked, but where the distance between ranks cannot be measured is?

Which data type can be answered as ‘0’ and allows for ratio comparisons (e.g. weight/height)?

What does “bias” mean in a statistical way?

What sanpling method ensures every number has an equal, independent chance of selection?

Which sampling method involves every k-th (random interval) individual from a list?

A bakery samples 20 people from three age groups (Teens, Adults, Seniors) to get satisfaction ratings. What is the method and data type?

A gym tracks weight loss by selecting every 15th member from a randomized list. What is the method and data type?