Statistical Sampling. Part I – Introduction. This video is designed to accompany pages 41-76 in Making Sense of Uncertainty Activities for Teaching Statistical Reasoning Van- Griner Publishing Company. Goal of Sampling.
Part I – Introduction
This video is designed to accompany
Making Sense of Uncertainty
Activities for Teaching Statistical Reasoning
Van-Griner Publishing Company
Goal of Sampling
Common Sense First
Sampling from Biased Lists
1936 Literary Digest poll that forecast Landon would defeat FDR by 57% to 43%.
The Digest used lists of telephone and automobile owners to select their sample, which targeted middle- and upper-class citizens who voted for Landon.
The lower classes voted for Roosevelt.
“If you had to do it over again, would you have children?”
So How Bad Was the Bias?
Newsday commissioned a nationwide poll of 1373 parents and used “statistical sampling.”
Found that 91% would have children again!
Biased samples tend to systematically favor certain outcomes.
With biased samples you can’t say anything meaningful about how good your estimates are.
The science of statistics is about what you can say when you take samples the right way.
Avoiding biased samples is just good common sense, whereas making meaningful statements from proper samples is the business of statistical science.