Abstract

The invention concerns a system of English language abstracting used to increase the search rate for an Index Search machine that, as an example makes use of magnetic record cards each having in a typical case 50 tracks for recording of information. To increase the rate at which groups of words can be compared, an abstract of each group of words is generated. On the magnetic card the text or groups of words are recorded on tracks 2 through 50 and the abstracts of these groups are recorded in track 1. When searching for a particular group of words, an abstract is generated for the group being sought. This abstract is then compared to the abstracts on track 1 of each card. If any of the abstracts match, the corresponding group of words on the card are searched in detail. For abstracts that do not match there is no need to search the corresponding group of words. Therefore, the need to search every group of words is eliminated, thus increasing the search rate.The abstracts are generated from the first and third characters of each word in the group of words. Each character to be used in the generation of the abstract is encoded into one of three groups which are equally probable over the distribution of characters in the English Language. The abstract for a group of words consists of the number of characters that fall in each of the three groups.