I wish to gather a sample of students at FAU in order to conduct a brief (ten minute) survey. I seek to gather data concerning dating behaviors and relationship attitudes among college students. I go to the breezeway and set up a table where students may opt to come by and complete the survey. In exchange for participating, students receive a $2 off coupon at Barnes & Noble. I set up the same table each day for a week so that students can also tell their friends to come by and complete this survey, thus maximizing the number of participants in my study. I ultimately collect data from 85 students whose mean age is 21 (standard deviation= 2.5).

 

Questions:

1. What is my sampling frame?
2. What sampling method did I use?
3. What might be some problems with this sampling method?
4. Will my sampling method provide my study with strong external validity? Why or why not?
5. How could I improve external validity in this study?
6. Since the standard deviation (SD) of the age of this group is 2.5, then that means 68% of my participants fell between what two ages?

 

See Trochim chapter https://conjointly.com/kb/sampling-statistical-terms/ Links to an external site. for information about "sampling frame" and "the 68, 95, 99% Rule"