Help in quantitative research. [+REP]

[Cath]

I have that exam tomorrow, shouldn't be too hard, but I need some help figuring out something.
We are currently analyzing different type of polls.

However, in every poll, I need to identify how the sampling has been done between those following ones:

1. Probability Samples
-Simple Random
-Systematic Random
-Stratified
-Multi-staged Cluster



2. Non-probability samples
-Quota
-Convenience
-Snowball
-Theoretical


I mean... I know the definition of them all, but when I do my exercises, I just never know which one was used.
Any tips to clearly figure out what kind of sample has been used by some words that are used in the context or something?
Need help. :c Will +REP

[Mod]

Need help.
Is this done yet?

If you still have difficulty categorizing them,
then I think you've memorized the definitions, but don't quite understand them?