enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Spectral element method - Wikipedia

    en.wikipedia.org/wiki/Spectral_element_method

    SEM is a Galerkin based FEM (finite element method) with Lagrange basis (shape) functions and reduced numerical integration by Lobatto quadrature using the same nodes. The pseudospectral method, orthogonal collocation, differential quadrature method, and G-NI are different names for the same method. These methods employ global rather than ...

  3. Simultaneously extracted metals and acid-volatile sulfide

    en.wikipedia.org/wiki/Simultaneously_extracted...

    In applying the SEM-AVS approach, two concentrations are determined: the total concentrations of all toxic heavy metals of interest, represented as [SEM], and the acid-volatile sulfide concentration, represented as [AVS]. [12] From these concentrations, the [SEM]/[AVS] ratio can be obtained, summarizing the results in a single value.

  4. Structural equation modeling - Wikipedia

    en.wikipedia.org/wiki/Structural_equation_modeling

    Structural equation modeling (SEM) is a diverse set of methods used by scientists for both observational and experimental research. SEM is used mostly in the social and behavioral science fields, but it is also used in epidemiology, [2] business, [3] and other fields. A common definition of SEM is, "...a class of methodologies that seeks to ...

  5. Partial least squares path modeling - Wikipedia

    en.wikipedia.org/wiki/Partial_least_squares_path...

    PLS-PM [4] [5] is a component-based estimation approach that differs from the covariance-based structural equation modeling.Unlike covariance-based approaches to structural equation modeling, PLS-PM does not fit a common factor model to the data, it rather fits a composite model.

  6. Path analysis (statistics) - Wikipedia

    en.wikipedia.org/wiki/Path_analysis_(statistics)

    In statistics, path analysis is used to describe the directed dependencies among a set of variables. This includes models equivalent to any form of multiple regression analysis, factor analysis, canonical correlation analysis, discriminant analysis, as well as more general families of models in the multivariate analysis of variance and covariance analyses (MANOVA, ANOVA, ANCOVA).

  7. Fisher's exact test - Wikipedia

    en.wikipedia.org/wiki/Fisher's_exact_test

    Most uses of the Fisher test involve, like this example, a 2 × 2 contingency table (discussed below). The p-value from the test is computed as if the margins of the table are fixed, i.e. as if, in the tea-tasting example, Bristol knows the number of cups with each treatment (milk or tea first) and will therefore provide guesses with the ...

  8. Standard error - Wikipedia

    en.wikipedia.org/wiki/Standard_error

    In many practical applications, the true value of σ is unknown. As a result, we need to use a distribution that takes into account that spread of possible σ' s. When the true underlying distribution is known to be Gaussian, although with unknown σ, then the resulting estimated distribution follows the Student t-distribution.

  9. Symmetric mean absolute percentage error - Wikipedia

    en.wikipedia.org/wiki/Symmetric_mean_absolute...

    where A t is the actual value and F t is the forecast value. The absolute difference between A t and F t is divided by half the sum of absolute values of the actual value A t and the forecast value F t. The value of this calculation is summed for every fitted point t and divided again by the number of fitted points n.