Discrimination method

Furthermore, the pattern structures in a representation space formed from raw input data are not necessarily linearly separable. A central issue, then, is feature extraction to transform the representation of observable features into some new representation in which the pattern classes are linearly separable. Since many practical problems are not linearly separable (Minsky and Papert, 1969), use of linear discriminant methods is especially dependent on feature extraction. 

Our research on human tissue discrimination methods deriving from MRI parameters is leading to the evolution of prescribed statistical methods for data screening, normalization and discrimination. These are driven by Prolog. In Prolog, sets of logical inferences... 

Preston KL (1991) Drug discrimination methods in human drug abuse liability evaluations, Br J Addict 86 1587-1594... 

In the class discrimination methods or hyperplane techniques, of which linear discriminant analysis and the linear learning machine are examples, the equation of a plane or hyperplane is calculated that separates one class from another. These methods work well if prior knowledge allows the analyst to assume that the test objects must... 

The complexity of the low temperature MCD spectra of the oxidized and reduced trinuclear cluster shows the multiplicity of the predominantly S — Fe charge transfer transitions that contribute to the absorption envelope. While MCD spectroscopy provides a method of resolving the electronic transitions, assignment cannot be attempted without detailed knowledge of the electronic structure. However, the complexity of the low temperature MCD spectra is useful in that it furnishes a discriminating method for determining the type and redox state of protein bound iron-sulfur clusters. Each well characterized type of iron-sulfur cluster, i.e. [2Fe-2S], [3Fe-4S], and [4Fe-4S], has been shown to have a characteristic low temperature MCD spectrum in each paramagnetic redox state (1)... 

Dudoit, S., Eridly, J., and Speed, P. (2002). Comparison of discrimination methods for the classification of tumors using gene expression data. /. Am. Stat. Assoc. 97, 77-87. 

Forina, M., Armanino, C., Castino, M., Ubigli, M. Multivariate Data Analysis as a Discriminating Method of the Origin of Wines, Vitis 25, 189 (1986)... 

QCM Values forVM at 20 and 25°C. Most GCM values for are based on group definitions that are more discriminative than those used in the models above. Examples are the method of Exner [29] to estimate Vm at 20°C and the method of Fedors [31] to estimate Vm at 25°C. GCM values have been reviewed by van Krevelen [11]. Highly discriminative methods have been developed by Dubois and Loukianoff [32] and by Constantinou et al. [33]. These methods are discussed briefly below. 

Photoconductance of n-type semiconductor oxides exposed to O9 or NO. Photocatalytic reactions involve the exchange of electrons between an excited semiconductor and at least one adsorbed reactant or surface species. Consequently, photoconductance measurements appear as a discriminating method to investigate these reactions. 

Supervised methods rely on some prior training of the system with objects known to belong to the class they define. Such methods can be of the discriminant or modeling types.11 Discriminant methods split the pattern space into as many regions as the classes encompassed by the training set and establish bounds that are shared by the spaces. These methods always classify an unknown sample as a specific class. The most common discriminant methods include discriminant analysis (DA),12 the K-nearest neighbor... 

The first task before beginning stress-testing studies is to gather all the relevant information about the compound. Information such as molecular structure, solubility, pA (s), known chemical instability, hygroscopicity, enantiomeric purity, etc. is important. In addition, previously established analytical methods may provide a starting point for development of more discriminating methods required for the separation of the complex mixtures which may result from stress degradation. 

Evaluating odor and flavor taints is frequently done with water, fatty food simulants (oil, chocolate, unsalted butter), hydrophilic powders (sugar, cornflour), or combined hydrophilic-hydrophobic matrices (milk or cream, biscuits) (Kilcast, 2003). The Robinson test often is used to evaluate materials for tainting potential. This test places the test material in a sealed container separated from the food simulant or test food at a relative humidity between 53% and 75%. After about 48 h, the test food is evaluated for taint compared to a control, using a discrimination method (Lord, 2003). Chocolate is frequently used as the food simulant for this test. Intensity of the taint may be evaluated using a... 

Many laboratories have used simple two-choice discrimination methods to investigate the mechanism or site of action of new compounds by examining those compounds in animals trained to discriminate a reference substance and known drag of abuse (Shannon and Holtzman 1976 Holtzman 1983 Brady et al. 1987 Shannon and Holtzman 1986 Colpaert 1987 Overton 1987 Hoffmeister 1988 Carboni et al. 1989 Holtzman 1990). 

The drug discrimination method has also been applied to study anxiolytic drugs using pentylenetetrazol at subconvulsive doses (Sherman and Lai 1979, 1980 Sherman et al. 1979 Lai and Sherman 1980). 

Colpaert FC (1987) Drug discrimination methods of manipulation, measurement, and analysis. In Bozarth MA (ed) Methods for Assessing the Reinforcing Properties of Abused Drugs. Springer-Verlag, New York, Berlin, Heidelberg, pp 341-372... 

There are many alternatives for modeling high pressure phase equilibria. Therefore, it is required a discrimination procedure capable to screen these models satisfactorily. In this work we have compared two discrimination methods in order to select the next experimental point. The first one is the Hunter-Reiner methodology that considers only the predicted response of each model according to the following equations ... 

Harper et al. have demonstrated a much better performance of probabilistic binary kernel discrimination method to screen large databases compared to... 

Various types of plots are available for testing special kinetic hypotheses. Some of these are used in problems at the end of this chapter. The reader is urged to st2irt with simple plots to get a feel for the data and judge what kinds of rate expressions might be suitable. Graphical schemes are useful for preliminary selection of models, but the statistical discrimination methods of Chapters 6 and 7 are recommended for the later stages. 

Stratified sampling is more likely to reveal uniformity problems than if less discriminating methods were used. A tool was developed and published (84) to aid formulation and process development scientists in troubleshooting content uniformity problems. The approach is that if stratified sample results were available for blend and/or product samples, the data will point the troubleshooter towards potential causes for uniformity problems in rank order of likelihood. Once potential root causes have been identified, areas for further investigation and possible corrective actions are also presented. 

Colpaert, F. C. (1987). Drug discrimination Methods of manipulation, measurement, and analysis. In M. A. Bozarth (Ed.), Methods of assessing the reinforcing properties of drugs 341-372). New York Springer-Verlag. 

One of the arguments against the use of discrimination methods [42] is that the set of models fi om which the best model is to be chosen is too limited. Hence one of the set must be identified as the best model even if the set does not contain the true model. The formal kinetic models in the accepted set (e.g.. Table 3.3.) are too simple to account for all the features of real processes. Modification of the models, however, results in an increased number of adjustable parameters. 

Specific proteins in biological fluids can be estimated by more discriminating methods, such as electrophoresis, specific binding techniques, or immunochemical methods. 

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