Bootstrap aggregatingBootstrap aggregating, also called bagging (from bootstrap aggregating), is a machine learning ensemble meta-algorithm designed to improve the stability and accuracy of machine learning algorithms used in statistical classification and regression. It also reduces variance and helps to avoid overfitting. Although it is usually applied to decision tree methods, it can be used with any type of method. Bagging is a special case of the model averaging approach.
Unethical human experimentationUnethical human experimentation is human experimentation that violates the principles of medical ethics. Such practices have included denying patients the right to informed consent, using pseudoscientific frameworks such as race science, and torturing people under the guise of research. Around World War II, Imperial Japan and Nazi Germany carried out brutal experiments on prisoners and civilians through groups like Unit 731 or individuals like Josef Mengele; the Nuremberg Code was developed after the war in response to the Nazi experiments.
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.
AdaBoostAdaBoost, short for Adaptive Boosting, is a statistical classification meta-algorithm formulated by Yoav Freund and Robert Schapire in 1995, who won the 2003 Gödel Prize for their work. It can be used in conjunction with many other types of learning algorithms to improve performance. The output of the other learning algorithms ('weak learners') is combined into a weighted sum that represents the final output of the boosted classifier. Usually, AdaBoost is presented for binary classification, although it can be generalized to multiple classes or bounded intervals on the real line.
VivisectionVivisection () is surgery conducted for experimental purposes on a living organism, typically animals with a central nervous system, to view living internal structure. The word is, more broadly, used as a pejorative catch-all term for experimentation on live animals but the term is rarely used by practising scientists. Human vivisection, such as live organ procurement, has been perpetrated as a form of torture.
Alternative educationAlternative education encompasses many pedagogical approaches differing from mainstream pedagogy. Such alternative learning environments may be found within state, charter, and independent schools as well as home-based learning environments. Many educational alternatives emphasize small class sizes, close relationships between students and teachers and a sense of community. The legal framework for such education varies by locality, and determines any obligation to conform with mainstream standard tests and grades.
Alternative schoolAn alternative school is an educational establishment with a curriculum and methods that are nontraditional. Such schools offer a wide range of philosophies and teaching methods; some have strong political, scholarly, or philosophical orientations, while others are more ad hoc assemblies of teachers and students dissatisfied with some aspect of mainstream or traditional education.
Unit 731, short for Manshu Detachment 731 and also known as the Kamo Detachment and the Ishii Unit, was a covert biological and chemical warfare research and development unit of the Imperial Japanese Army that engaged in lethal human experimentation and biological weapons manufacturing during the Second Sino-Japanese War (1937–1945) and World War II. It killed an estimated 200,000 to 300,000 people. It was based in the Pingfang district of Harbin, the largest city in the Japanese puppet state of Manchukuo (now Northeast China, formerly named Manchuria) and had active branch offices throughout China and Southeast Asia.
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.
Second law of thermodynamicsThe second law of thermodynamics is a physical law based on universal experience concerning heat and energy interconversions. One simple statement of the law is that heat always moves from hotter objects to colder objects (or "downhill"), unless energy in some form is supplied to reverse the direction of heat flow. Another definition is: "Not all heat energy can be converted into work in a cyclic process." The second law of thermodynamics in other versions establishes the concept of entropy as a physical property of a thermodynamic system.
