1457	 Data Manipulation and Programming Problems in Automatic Information Retrieval	 Automatic information retrieval programs require the manipulation of a variety of different data structures including linear text sparse matrices and tree or list structures. The main data manipulations to be performed in automatic information systems are first briefly reviewed. A variety of data representations which have been used to describe structured information are then examined and the characteristics of various processing languages are outlined in the light of the procedures requiring implementation. Advantages of these programming languages for the retrieval application are examined and suggestions are made for the design of programming facilities to aid in information retrieval.
