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Letter-Number Sequencing Recall a series of numbers in increasing order and letters in alphabetical order. Working memory, attention, mental control Processing Speed Symbol Search View rows of symbols and target symbols, and mark whether or not the target symbols appear in each row. Processing speed Coding Transcribe a digit-symbol code using a ...
Risk matrix. A risk matrix is a matrix that is used during risk assessment to define the level of risk by considering the category of likelihood (often confused with one of its possible quantitative metrics, i.e. the probability) against the category of consequence severity. This is a simple mechanism to increase visibility of risks and assist ...
The sample mean ( sample average) or empirical mean ( empirical average ), and the sample covariance or empirical covariance are statistics computed from a sample of data on one or more random variables . The sample mean is the average value (or mean value) of a sample of numbers taken from a larger population of numbers, where "population ...
Matrix (mathematics) An m × n matrix: the m rows are horizontal and the n columns are vertical. Each element of a matrix is often denoted by a variable with two subscripts. For example, a2,1 represents the element at the second row and first column of the matrix. In mathematics, a matrix ( pl.: matrices) is a rectangular array or table of ...
A doubly stochastic matrix is a square matrix of nonnegative real numbers with each row and column summing to 1. In the same vein, one may define a probability vector as a vector whose elements are nonnegative real numbers which sum to 1. Thus, each row of a right stochastic matrix (or column of a left stochastic matrix) is a probability vector.
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Calculus. In vector calculus, the Jacobian matrix ( / dʒəˈkoʊbiən /, [ 1][ 2][ 3] / dʒɪ -, jɪ -/) of a vector-valued function of several variables is the matrix of all its first-order partial derivatives. When this matrix is square, that is, when the function takes the same number of variables as input as the number of vector components ...
The sample covariance matrix (SCM) is an unbiased and efficient estimator of the covariance matrix if the space of covariance matrices is viewed as an extrinsic convex cone in Rp×p; however, measured using the intrinsic geometry of positive-definite matrices, the SCM is a biased and inefficient estimator. [ 1]