operational hypothesis
21Ecosystem services — Pollination by a bumblebee, a type of ecosystem service Humankind benefits from a multitude of resources and processes that are supplied by natural ecosystems. Collectively, these benefits are known as ecosystem services and include products like …
22Ecology — For other uses, see Ecology (disambiguation). Ecology …
23Chernobyl disaster — This article is about the 1986 nuclear plant accident in Ukraine. For other uses, see Chernobyl (disambiguation). Chernobyl disaster …
24Kuiper belt — Known objects in the Kuiper belt, derived from data from the Minor Planet Center. Obje …
25Simulation — Simulator redirects here. For other uses, see Simulator (disambiguation). For other uses, see Simulation (disambiguation). Not to be confused with Stimulation. Wooden mechanical horse simulator during WWI. Simulation is the imitation of some real …
26Modern portfolio theory — Portfolio analysis redirects here. For theorems about the mean variance efficient frontier, see Mutual fund separation theorem. For non mean variance portfolio analysis, see Marginal conditional stochastic dominance. Modern portfolio theory (MPT) …
27Nobel Prizes — ▪ 2009 Introduction Prize for Peace The 2008 Nobel Prize for Peace was awarded to Martti Ahtisaari, former president (1994–2000) of Finland, for his work over more than 30 years in settling international disputes, many involving ethnic,… …
28ancient Greek civilization — ▪ historical region, Eurasia Introduction the period following Mycenaean civilization, which ended in about 1200 BC, to the death of Alexander the Great, in 323 BC. It was a period of political, philosophical, artistic, and scientific… …
29Decompression (diving) — Divers decompressing in the water at the end of a dive Decompression in the context of diving derives from the reduction in ambient pressure experienced by the diver during the ascent at the end of a dive or hyperbaric exposure and refers to both …
30Charles Sanders Peirce —  B …
