Wondering how many people in the United States have a smartphone? If you poll 20 people on the street, your survey won’t be representative of the entire American population. But if you just want to ...

Overview: This webinar covers the statistical methods used to calculate sample sizes for both attribute and variables data. Methods for collecting the sample will be covered. Every sampling plan has ...

Power analyses and sample size calculations are important parts of many research projects. Often, before data are even collected, it is necessary to calculate and justify the required sample size for ...

Precedents set in the historic Barr case continue to raise questions over suitable sample-size criteria. "... the number of retests performed before a firm concludes that an unexplained out of ...