Mean squared errorIn statistics, the mean squared error (MSE) or mean squared deviation (MSD) of an estimator (of a procedure for estimating an unobserved quantity) measures the average of the squares of the errors—that is, the average squared difference between the estimated values and the actual value. MSE is a risk function, corresponding to the expected value of the squared error loss. The fact that MSE is almost always strictly positive (and not zero) is because of randomness or because the estimator does not account for information that could produce a more accurate estimate.
Species richnessSpecies richness is the number of different species represented in an ecological community, landscape or region. Species richness is simply a count of species, and it does not take into account the abundances of the species or their relative abundance distributions. Species richness is sometimes considered synonymous with species diversity, but the formal metric species diversity takes into account both species richness and species evenness. Depending on the purposes of quantifying species richness, the individuals can be selected in different ways.
OmbrotrophicOmbrotrophic ("cloud-fed"), from Ancient Greek ὄμβρος (ómvros) meaning "rain" and τροφή (trofí) meaning "food"), refers to soils or vegetation which receive all of their water and nutrients from precipitation, rather than from streams or springs. Such environments are hydrologically isolated from the surrounding landscape, and since rain is acidic and very low in nutrients, they are home to organisms tolerant of acidic, low-nutrient environments. The vegetation of ombrotrophic peatlands is often bog, dominated by Sphagnum mosses.
Cherry pickingCherry picking, suppressing evidence, or the fallacy of incomplete evidence, is the act of pointing to individual cases or data that seem to confirm a particular position while ignoring a significant portion of related and similar cases or data that may contradict that position. Cherry picking may be committed intentionally or unintentionally. The term is based on the perceived process of harvesting fruit, such as cherries. The picker would be expected to select only the ripest and healthiest fruits.
OstracodOstracods, or ostracodes, are a class of the Crustacea (class Ostracoda), sometimes known as seed shrimp. Some 70,000 species (only 13,000 of which are extant) have been identified, grouped into several orders. They are small crustaceans, typically around in size, but varying from in the case of the marine Gigantocypris (the largest known freshwater species is Megalocypris princeps, which reach 8mm in lenght).