I wanted to know if anyone had a good question that would help remember the differences. I find that there is a blurry area when it comes to these types of questions...
Simple Random - Every object has equal chance of being selected from a population
Cluster - "Break" population into group (cluster) and randomly sample n groups. (Mostly use when geographic coverage is huge because the cost of traveling to all group is high).
Stratified - Classify population according to certain characteristics (e.g. Gender, Age etc). Next, randomly select objects from each classification. Group all the objects into a final sample.
发表于 2011-7-13 16:50
| 