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  2. Estimation of covariance matrices - Wikipedia

    en.wikipedia.org/wiki/Estimation_of_covariance...

    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 R p×p; however, measured using the intrinsic geometry of positive-definite matrices, the SCM is a biased and inefficient estimator. [1]

  3. Life-cycle cost analysis - Wikipedia

    en.wikipedia.org/wiki/Life-cycle_cost_analysis

    Life-cycle cost analysis (LCCA) is an economic analysis tool to determine the most cost-effective option to purchase, run, sustain or dispose of an object or process. The method is popular in helping managers determine economic sustainability by figuring out the life cycle of a product or process.

  4. Covariance matrix - Wikipedia

    en.wikipedia.org/wiki/Covariance_matrix

    Throughout this article, boldfaced unsubscripted and are used to refer to random vectors, and Roman subscripted and are used to refer to scalar random variables.. If the entries in the column vector = (,, …,) are random variables, each with finite variance and expected value, then the covariance matrix is the matrix whose (,) entry is the covariance [1]: 177 ...

  5. Product life-cycle theory - Wikipedia

    en.wikipedia.org/wiki/Product_life-cycle_theory

    The Product Life Cycle Theory is an economic theory that was developed by Raymond Vernon in response to the failure of the Heckscher–Ohlin model to explain the observed pattern of international trade. The theory suggests that early in a product's life-cycle all the parts and labor associated with that product come from the area where it was ...

  6. Partial least squares regression - Wikipedia

    en.wikipedia.org/wiki/Partial_least_squares...

    Partial least squares (PLS) regression is a statistical method that bears some relation to principal components regression and is a reduced rank regression [1]; instead of finding hyperplanes of maximum variance between the response and independent variables, it finds a linear regression model by projecting the predicted variables and the observable variables to a new space of maximum ...

  7. Life-cycle assessment - Wikipedia

    en.wikipedia.org/wiki/Life-cycle_assessment

    Life cycle inventory (LCI) analysis involves creating an inventory of flows from and to nature (ecosphere) for a product system. [32] It is the process of quantifying raw material and energy requirements, atmospheric emissions, land emissions, water emissions, resource uses, and other releases over the life cycle of a product or process. [33]

  8. Product life-cycle management (marketing) - Wikipedia

    en.wikipedia.org/wiki/Product_life-cycle...

    Product life-cycle management (PLM) is the succession of strategies by business management as a product goes through its life-cycle. The conditions in which a product is sold (advertising, saturation) changes over time and must be managed as it moves through its succession of stages.

  9. Pearson correlation coefficient - Wikipedia

    en.wikipedia.org/wiki/Pearson_correlation...

    Pearson's correlation coefficient is the covariance of the two variables divided by the product of their standard deviations. The form of the definition involves a "product moment", that is, the mean (the first moment about the origin) of the product of the mean-adjusted random variables; hence the modifier product-moment in the name.