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Least explanatory variable

Independent variables P-value Power Also known as predictors or explanatory variables Another name for significance level usually 0.005 The effect of the experimental conditions on the dependent variable relative to sampling fluctuation. When the effect is maximized, the experiment is more powerful. Power can also he defined as the probability that there will not be a Type II error (1-/1). Conventionally, power should be at least 0.07... [Pg.865]

Least Squares Regression with an Explanatory Variable... [Pg.219]

The least squares fitting of approximate functional relationships to data with even multidimensional explanatory variable x typically goes under the (unfortunately obscure) name of multiple regression analysis, and is given an introductory treatment in most engineering statistics textbooks, including, for example, the ones by Devore,4 Vardeman and Jobe,5 and Vardeman6 listed in the references. A lucid and rather complete treatment of the subject can also be found in the book by Neter et al.7... [Pg.183]

For a given sequence, Bloch equations give the relationship between the explanatory variables, x, and the true response, i]. The / -dimensional vector, 0, corresponds to the unknown parameters that have to be estimated x stands for the m-dimensional vector of experimental factors, i.e., the sequence parameters, that have an effect on the response. These factors may be scalar (m — 1), as previously described in the TVmapping protocol, or vector (m > 1) e.g., the direction of diffusion gradients in a diffusion tensor experiment.2 The model >](x 0) is generally non-linear and depends on the considered sequence. Non-linearity is due to the dependence of at least one first derivative 5 (x 0)/50, on the value of at least one parameter, 6t. The model integrates intrinsic parameters of the tissue (e.g., relaxation times, apparent diffusion coefficient), and also experimental nuclear magnetic resonance (NMR) factors which are not sufficiently controlled and so are unknown. [Pg.214]

Uses (6) formulas, we can estimate the explanatory variables 0-th quintile on coal consumption. Regression results are shown in Table 1. Unlike the least squares estimator, high efficiency over a wide rang of error distributions. [Pg.1250]

Multivariate Forecasts of a given variable depend at least partly on values of one or more additional variables, called explanatory variables. Models of this type are usually called causal models, and include Multiple Regression, and Econometric Models. [Pg.49]

Various attempts have been made to use pattern recognition [24, 25] in QSAR studies and successful applications have been reported. Soft modeling techniques, e.g. the partial least squares (PLS) method [26, 27], now offer better opportunities. With the help of this principal component-like method the explanatory power of many, even hundreds or thousands of variables can be used for a limited number of objects, a task being absolutely impossible in regression analysis in which the number of objects must always be larger than the number of variables. [Pg.6]

Partial least squares projection of latent structures (PLS) is a method for relating the variahons in one or several response variables (Y variables or dependent variables) to the variations of several predictors (X variables), with explanatory or predictive purposes [12-14]. PLS performs particularly well when the various X variables express common information, i.e., when there is a large amount of correlation or even collinearity among them. PLS is a bilinear method where information in the original X data is projected onto a small number of underlying ( latent ) variables to ensure that the first components are those that are most relevant for predicting the Y variables. Interpretahon of the relationship between X data and Y data is then simplified, as this relahonship is concentrated on the smallest possible number of components [15]. [Pg.154]

Partial least squares projection of latent structures (PLS) is a method for relating the variations in one or several response variables (Y variables or dependent variables) to the variations of several predictors (X variables), with explanatory or predictive purposes. [Pg.165]


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Explanatory

Least Squares Regression with an Explanatory Variable

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