Survey Design & Administration for Assistance & P2 Programs

The webinar included the following presentations:

Andrew Stoeckle, ABT Associates
Survey Design & Administration

Tool to Estimate Sample Size Given a Specified Confidence Level That You Want to Achieve, MA DEP
The user enters:

• Whether you want to be correct 80%, 90%, 95%, 99% or what ever % of the time (the confidence interval)
• Your desired precision: the estimated true range of the answer (e.g., plus or minus 10%, 20%, 5%, or whatever % you specify); this is called the error (example: a test score where the student got a 93 plus or minus 10 points)
• The universe of facilities in the population

With all of that information, the calculator tells you the minimum sample size you need. You can play around with the confidence interval and error to see how well you would do with a sample size you can afford.

Confidence Interval Calculator Tool Calculates the Confidence Level of Your Result, MA DEP
The user enters:

• Your results (e.g., 80% of the population answered yes)
• Your sample size
• The universe of facilities in the population
• The desired confidence interval (e.g., 95% sure you achieved a representative sample)

With all of that information the calculator tells you the precision you ended up with (e.g., my answer is 80% plus or minus 20)

Informative Links
http://www.statpac.com/surveys/
http://www.surveysystem.com/sdesign.htm
http://www.sysurvey.com/tips/arsham.htm#rwpoi