This kind of understanding is critical for research aimed at causal inference--including not just natural experiments
, but also conventional observational studies--as Maldonado et al.
6) However, a previous natural experiment
, which used data from the closure of a large Utah Valley steel mill between August 1986 and September 1987, did not find a difference in birth weights between babies born before, during, or after the closure.
about extrapolating beyond natural experiments
, when Klausner urges
, which compare two countries with similar social, economic, cultural, and religious characteristics--but with differing approaches to family planning programs--also demonstrate the powerful impact of voluntary family planning.
Economists and political scientists describe recent developments in studying corruption based on laboratory, field, and natural experiments
are in fashion in Social Sciences.
Research by Professor Simon Capewell and Dr Martin O'Flaherty at the Institute of Psychology, Health and Well-being, looked at evidence from clinical trials and natural experiments
He was always looking for natural experiments
of this kind, and a century before Karl Popper, Lyell claimed that his technique was to constantly try to disprove his working hypothesis, which was later called uniformitarianism by William Whewell.
Quasi-static and dynamic natural experiments
with a part of the deformation zone revealed that damages lead to changes in the characteristics of elements.
The title, Saggi di Naturali Esperienze, can be roughly translated as Selected Natural Experiments
, representing a tiny fraction of the experimenters' decade of work.
The evidence for this conclusion comes from three natural experiments
and a sophisticated statistical analysis of three large data bases.
Another problem with relying on natural experiments
is that comparisons of their results with longstanding practices rarely present sharp contrasts.