Designing SENSE (a software environment for social science rEsearch)
Authors: Fiddian N. J. , Gray W. A. , Read M. W. 
Published: April 2007

In most general purpose computer systems there is a wide variety
of software available to users. Such software is usually provided
in one of three organisational forms - routines in a library;
collections of related functions grouped in a package with a common
interface; independent programs called through operating system
commands. This interdependent tripartite structure creates problems
for non-sophisticated users as it involves different levels of user
interface complexity.At the routine level a user must write
programs in an appropriate host programming language to use the
software. If he wishes to use a selection of routines written in
incompatible languages then he may have to familiarise himself with
more than one host language. In each language he must be aware of
the calling conventions for routines, the possible representations
of various types of data, the methods of passing parameters and the
ways of inputting and outputting data to and from the external
environment. This type of interface occurs with libraries like NAG
and IMSL.

In the case of packages the imperative user interface is usually
somewhat simpler, consisting essentially of a name identifying the
function required and some associated parameters which identify
variables, labels, files, options, control and code values, etc as
appropriate. However, function calls of this form must normally be
preceded by a non-trivial amount of declarative and other "red
tape" information expressed in the package interface language.
Also, package environments can be restrictive in that the user is
constrained to the types of data structure and analysis supported
by the chosen package unless he is prepared to write programs to
transform his data for other packages or to analyse it
independently. SPSS is typical of this kind of package.

When software facilities are provided at the program level, the
user interface often consists simply of one-line program invocation
commands written in the local operating system's command language,
with program options and data files identified by command
parameters. Common examples of such facilities are sort and
archiving programs. A program level interface becomes even simpler,
and at the same time more powerful, if command sequences can be
formed into parameterised command procedures and if programs are
enabled to conmlunicate directly with one another without the need
for explicit intermediate files.

In the latter type of environment the application software user
generally finds that there are analytic program tools available to
meet only some of his requirements. Consequently he has to embrace
either or both of the other levels in addition in order to increase
the analytic power available to him. Transfer between levels is not
easily accomplished in most systems as facilities do not normally
exist to help the user move data between levels. This difficulty
comes on top of the obvious problem of having to master more than
one interface and more than one level of complexity.

In the SENSE project (11), which is funded by the U.K. Social
Science Research Council, we are creating a prototype computing
environment for social science researchers which can accommodate
non-sophisticated users. The aim is to provide an integrated
environment where such users will have a complete range of
application software available (packages, routines and programs)
through a single, simple user interface. We believe that this can
be achieved by exploiting and extending the concept of software
tools propounded by Kernighan and Plauger (19), so that as far as
possible all software can be used through a program level
interface, with its attendant advantages. Following Kernighan and
Plauger we believe that software tools "can be used to create a
comfortable and effective interface to existing programs", as well
as providing an ideal model for the structuring of brand new
application software. This paper will consider various aspects of
the initial design of the SENSE software environment with
particular reference to the importance of software tools in that
design.