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Eigenvalues and eigenvectors. In linear algebra, it is often important to know which vectors have their directions unchanged by a given linear transformation. An eigenvector ( / ˈaɪɡən -/ EYE-gən-) or characteristic vector is such a vector. Thus an eigenvector of a linear transformation is scaled by a constant factor when the linear ...
Information and communications technology ( ICT) is an extensional term for information technology (IT) that stresses the role of unified communications [1] and the integration of telecommunications ( telephone lines and wireless signals) and computers, as well as necessary enterprise software, middleware, storage and audiovisual, that enable ...
Joseph Eugene Stiglitz ( / ˈstɪɡlɪts /; born February 9, 1943) is an American New Keynesian economist, [2] a public policy analyst, and a full professor at Columbia University. He is a recipient of the Nobel Memorial Prize in Economic Sciences (2001) [3] and the John Bates Clark Medal (1979). [4] He is a former senior vice president and ...
Principal component analysis (PCA) is a linear dimensionality reduction technique with applications in exploratory data analysis, visualization and data preprocessing. The data is linearly transformed onto a new coordinate system such that the directions (principal components) capturing the largest variation in the data can be easily identified.
The IP code or ingress protection code indicates how well a device is protected against water and dust. It is defined by the International Electrotechnical Commission (IEC) under the international standard IEC 60529 [1] which classifies and provides a guideline to the degree of protection provided by mechanical casings and electrical enclosures ...
Leo Tolstoy at age 20, c. 1848. Tolstoy was born at Yasnaya Polyana, a family estate 12 kilometres (7.5 mi) southwest of Tula, and 200 kilometres (120 mi) south of Moscow. He was the fourth of five children of Count Nikolai Ilyich Tolstoy (1794–1837), a veteran of the Patriotic War of 1812, and Princess Mariya Tolstaya (née Volkonskaya; 1790 ...
The 828-metre (2,717 ft) tall Burj Khalifa in Dubai has been the tallest building since 2010. The Burj Khalifa has been classified as megatall. A diagram showing the tallest buildings as of 2024 This is a list of the tallest buildings.Tall buildings, such as skyscrapers, are intended here as enclosed structures with continuously occupiable floors and a height of at least 340 metres (1,120 ft).
