The Pew Research Center’s Internet & American Life Project, a nonprofit, nonpartisan research organization, provides free data and analysis on the social
As just about every statistics student can attest, Simpson's Paradox — a statistical phenomenon where an apparent trend is reversed when you look at subgroups — is notoriously hard to explain. You can look at examples — say, the fact that US wages are rising overall, but dropping within every educational group — but that don't really help to explain the paradox. But it's not really paradox at all, but simply the fact that the disparate rate at which members of the study join the subgroups isn't accounted for in the analysis. To demonstrate this effect, the Visualizing Urban Data...
Five years ago, a team of researchers from Google announced a remarkable achievement in one of the world’s top scientific journals, Nature. Without needing the results of a single medical check-up, they were nevertheless able to track the spread of
F. Kooti, N. Hodas, und K. Lerman. Proceedings of the eighth International AAAI Conference on Weblogs and Social Media, Seite 266--274. AAAI, AAAI Press, (Juni 2014)