MIDAS(ID:7019/mid009)Data visualisation languagefor Michigan Interactive Data Analysis System References: MIDAS is a sophisticated statistical system which is capable of performing a wide range of analyses and data manipulations. The multigroup command within MIDAS performs analyses requested by the user and then invokes our graphics routines and the supporting IG routines (see note 3 below) for plotting. Extract: INTRODUCTION INTRODUCTION Social scientists are a large group of potential users of computer graphics. They make heavy use of computers in both research and teaching. When they use computers they are accustomed to sophisticated software and unsophisticated devices. They rarely write special purpose programs and only a small subset use special hardware. Instead, they rely on high quality, multipurpose-software packages of canned programs. These and other characteristics have implications for the design of graphics software and hardware. These potential users will expect graphic software to be easy to use, powerful, inexpensive and device independent. If computer graphics evolves in these directions social scientists will become major consumers. Computer graphics can aid the social scientist who is involved in data analysis in two distinct ways. First, computer graphic displays can be used after the research process to communicate research results to others in publications, in presentations and in teaching. This use requires that graphs be clearly labelled and adjustable in format. Second, computer graphics can be used during the research process to communicate results to the primary researcher. This can be accomplished by embedding the graphics within data analysis software. This use requires that the graphics be obtained easily in addition to the traditional printout of results; ease of use is more important than flexibility of format or elegance of labelling. We have developed graphic software to satisfy the perceived basic needs and expectations of the social scientists and which have been well received and utilized at the University of Michigan. It is embedded in the interactive statistical system, MIDAS,[1] and appears as a stand alone interactive prompter, GRAPH.[2] In the future this software may be available more generally over a national computer network. Our graphic software includes a set of modules which correspond to the visual components of a display, such as an axis with tic marks and labels or a legend. This modularity provides extensibility of the set of available displays with minimal effort. Our software in turn employs the University of Michigan Integrated Graphics library [3] to define a visual component as a set of device-independent lines or text strings. The Integrated Graphics routines handle all graphic device communications including that for storage tube terminals and the CalComp ploter. We are not attempting in this paper to describe the internal design of the software we have produced. Our purpose is to describe the social science computing environment and the external form of the graphic software designed both to fit that environment and to introduce social scientists to computer graphics. in Proceedings of the 3rd annual conference on Computer graphics and interactive techniques, July 14-16, 1976, Philadelphia, Pennsylvania view details |