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J D Holliday

Publications and source records attributed to J D Holliday.

3 recordsLinked to original sources

Grouping of coefficients for the calculation of inter-molecular similarity and dissimilarity using 2D fragment bit-strings.

This paper compares 22 different similarity coefficients when they are used for searching databases of 2D fragment bit-strings. Experiments with the National Cancer Institute s AIDS and IDAlert databases show that the coefficients fall into several well-marked clusters, in which the members of a cluster will produce comparable rankings of a set of molecules. These clusters provide a basis for selecting combinations of coefficients for use in data fusion experiments. The results of these experiments provide a simple way of increasing the effectiveness of fragment-based similarity searching systems.

Acquired Immunodeficiency Syndrome↗

Using a genetic algorithm to identify common structural features in sets of ligands.

This article describes a program for pharmacophore mapping, called MPHIL (Mapping Pharmacophores in Ligands). Given as input a set of molecules that exhibit some common biological activity, MPHIL identifies the smallest 3D pattern of pharmacophore points that has at least m (a user-defined parameter) points in common with each of the input molecules. The program thus differs from existing programs for pharmacophore mapping in that it does not require all of the molecules to share exactly the same pattern of points, although it will find such a common pattern if it does, indeed, exist. MPHIL uses a genetic algorithm (GA) approach in which an initial, and very rapid, GA is used to suggest possible combinations of points that are then processed by the second GA to yield the final 3D pattern.

Algorithms↗

Effectiveness of retrieval in similarity searches of chemical databases: a review of performance measures.

This article reviews measures for evaluating the effectiveness of similarity searches in chemical databases, drawing principally upon the many measures that have been described previously for evaluating the performance of text search engines. The use of the various measures is exemplified by fragment-based 2D similarity searches on several databases for which both structural and bioactivity data are available. It is concluded that the cumulative recall and G-H score measures are the most useful of those tested.

Chemical Phenomena↗