I want to share some thoughts on random variables with a broader perspective:

A random variable can be thought of as any individual, item, or entity that has an equal chance of being selected from a set of similar variables to be included in a sample. What makes it "random" is the uncertainty in how it will behave or respond within the sample. In other words, we cannot predict the exact outcome or behavior of the variable in advance.

Importantly, random variables are not chosen based on the answers we expect them to provide. Instead, they are part of a sample population that may be chosen according to the research question.

With that in mind, here$$s a question for the class:

What is the difference between selecting a variable based on the expected outcome and selecting a sample population based on the research question? Feel free to use examples to illustrate your point