Cross-validation (statistics)Cross-validation, sometimes called rotation estimation or out-of-sample testing, is any of various similar model validation techniques for assessing how the results of a statistical analysis will generalize to an independent data set. Cross-validation is a resampling method that uses different portions of the data to test and train a model on different iterations. It is mainly used in settings where the goal is prediction, and one wants to estimate how accurately a predictive model will perform in practice.
Indian literatureIndian literature refers to the literature produced on the Indian subcontinent until 1947 and in the Republic of India thereafter. The Republic of India has 22 officially recognised languages. The earliest works of Indian literature were orally transmitted. Sanskrit literature begins with the oral literature of the Rig Veda, a collection of literature dating to the period 1500–1200 BCE. The Sanskrit epics Ramayana and Mahabharata were subsequently codified and appeared towards the end of the 2nd millennium BCE.
PresentThe present is the period of time that is occurring now. The present is contrasted with the past, the period of time that has already occurred, and the future, the period of time that has yet to occur. It is sometimes represented as a hyperplane in space-time, typically called "now", although modern physics demonstrates that such a hyperplane cannot be defined uniquely for observers in relative motion. The present may also be viewed as a duration.
British literatureBritish literature is literature from the United Kingdom of Great Britain and Northern Ireland, the Isle of Man, and the Channel Islands. This article covers British literature in the English language. Anglo-Saxon (Old English) literature is included, and there is some discussion of Latin and Anglo-Norman literature, where literature in these languages relate to the early development of the English language and literature. There is also some brief discussion of major figures who wrote in Scots, but the main discussion is in the various Scottish literature articles.
Weak measurementIn quantum mechanics (and computation & information), weak measurements are a type of quantum measurement that results in an observer obtaining very little information about the system on average, but also disturbs the state very little. From Busch's theorem the system is necessarily disturbed by the measurement. In the literature weak measurements are also known as unsharp, fuzzy, dull, noisy, approximate, and gentle measurements. Additionally weak measurements are often confused with the distinct but related concept of the weak value.
Thermal conductivityThe thermal conductivity of a material is a measure of its ability to conduct heat. It is commonly denoted by , , or . Heat transfer occurs at a lower rate in materials of low thermal conductivity than in materials of high thermal conductivity. For instance, metals typically have high thermal conductivity and are very efficient at conducting heat, while the opposite is true for insulating materials like mineral wool or Styrofoam.
Thirty Years' WarThe Thirty Years' War was one of the longest and most destructive conflicts in European history, lasting from 1618 to 1648. Fought primarily in Central Europe, an estimated 4.5 to 8 million soldiers and civilians died as a result of battle, famine, and disease, while some areas of what is now modern Germany experienced population declines of over 50%. Related conflicts include the Eighty Years' War, the War of the Mantuan Succession, the Franco-Spanish War, the Dutch-Portuguese War and the Portuguese Restoration War.
Statistical model validationIn statistics, model validation is the task of evaluating whether a chosen statistical model is appropriate or not. Oftentimes in statistical inference, inferences from models that appear to fit their data may be flukes, resulting in a misunderstanding by researchers of the actual relevance of their model. To combat this, model validation is used to test whether a statistical model can hold up to permutations in the data.
Eighty Years' WarThe Eighty Years' War or Dutch Revolt (Nederlandse Opstand) (c. 1566/1568–1648) was an armed conflict in the Habsburg Netherlands between disparate groups of rebels and the Spanish government. The causes of the war included the Reformation, centralisation, taxation, and the rights and privileges of the nobility and cities. After the initial stages, Philip II of Spain, the sovereign of the Netherlands, deployed his armies and regained control over most of the rebel-held territories.
Measurement in quantum mechanicsIn quantum physics, a measurement is the testing or manipulation of a physical system to yield a numerical result. A fundamental feature of quantum theory is that the predictions it makes are probabilistic. The procedure for finding a probability involves combining a quantum state, which mathematically describes a quantum system, with a mathematical representation of the measurement to be performed on that system. The formula for this calculation is known as the Born rule.
