advantages and disadvantages of at least 2 different sampling methods, psychology homework help

Discuss the advantages and disadvantages of at least 2 different sampling methods. Describe how researchers go about selecting a sampling strategy. What role does the research question play in choosing the sample? What does it mean to have a representative sample and why is this vital to the outcome of the study? You may wish to incorporate some of the scholarly sources you have been reviewing for your research project within your discussion.

Here are a couple good resources for this assignment –

2) Here is a good site that discusses sampling: 

http://www.socialresearchmethods.net/kb/sampprob.php . 

3) To find more information about the experimental method, you can go to: http://allpsych.com/psychology101/experiment.html.