Populations and samples used in research

Why would you use a small sample to draw inference about a large population? 2. What is the difference between a sample parameter (X-bar and s) and a proportion parameter (ρ)? 3. When would you use a two population test with a small sample size at your place of employment, in your education, or in politics? 4. When testing two populations with small sample sizes, do both sample sizes have to be identical? Why or why not? 5. What are the differences among a proportion, a percentage, and a ratio? 6. What do you do when testing two populations, if one sample’s size is small and the other sample’s size is large?