Quantitative evaluation library searching

The Evaluate menu is primarily intended to derive results from existing spectra. This could be a quantitative data analysis, peak identification or a library search. These functions do not alter the spectrum files. The Evaluate pull-down menu is given in Fig. 11.1. 

Comparisons of alternative library searching methods within IR searching have been reported. Delaney et al. developed a method for quantitative evaluation of the performance of library searching systems that they termed QELS. They compared the closest matches from a standard infrared spearal library to their index positions in a list of closest matches that was drawn from a test library. A weighted sum was calculated from the lists of index positions and then normalized. A figure of merit is calculated that has the advantage that it does not depend on the similarity metric, although it does depend on the test library size. 

Harrington and Isenhour developed a quantitative reliability metric (QRM) for determining the reliability of library searching methods with infrared spectra. They report applying the metric for evaluating the reliability of library searches for unknown target spectra and using the measure for de-... 

The evaluation of spectra will be discussed separately for qualitative and quantitative analysis. Particular emphasis will be laid (i) on state-of-the-art methods for searching spectra in spectral libraries or searching for spectroscopic information in data banks and on (ii) procedures for multivariate data analysis. 

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