Feb 3, 2016 07:43 PM
Behind The Numbers: Polling Debate
http://blogs.wsj.com/numbers/behind-the-...od=WSJBlog#
EXCERPT: Opinion polls based on probability samples have accurately reflected public sentiment for decades. But declining response rates and the time and expense required to collect the data has spurred interest in a fast and cheap alternative: online polls, which typically rely on nonprobability samples.
Probability surveys work because everyone in the population has an equal chance of being selected, and the random sample is representative of the entire group. The resemblance of nonprobability samples to the target population is unknown. [...] “We are at a point in history where there is the least clarity about how to go forward,” said Frederick Conrad, a professor in the Survey Research Center at the University of Michigan. “Big brains are thinking about this and talking about this, but it’s far from resolved. ” ...
Infinite sums and China's demographics
https://plus.maths.org/content/population-growth
EXCERPT: China has just revoked its one-child policy. What better occasion to explore the mathematics of population growth with an example. You may be surprised at the result....
http://blogs.wsj.com/numbers/behind-the-...od=WSJBlog#
EXCERPT: Opinion polls based on probability samples have accurately reflected public sentiment for decades. But declining response rates and the time and expense required to collect the data has spurred interest in a fast and cheap alternative: online polls, which typically rely on nonprobability samples.
Probability surveys work because everyone in the population has an equal chance of being selected, and the random sample is representative of the entire group. The resemblance of nonprobability samples to the target population is unknown. [...] “We are at a point in history where there is the least clarity about how to go forward,” said Frederick Conrad, a professor in the Survey Research Center at the University of Michigan. “Big brains are thinking about this and talking about this, but it’s far from resolved. ” ...
Infinite sums and China's demographics
https://plus.maths.org/content/population-growth
EXCERPT: China has just revoked its one-child policy. What better occasion to explore the mathematics of population growth with an example. You may be surprised at the result....