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 ...

If a tax impact study, derived from observations on income tax returns, is to provide tax estimates with the same margin of error and significance level for each ...