More information on STASEL, its use and development is available in an article by two of the developers:

Payette, Julie and Graeme Hirst. \"An Intelligent Computer-Assistant for Stylistic Instruction.\" Computers and the Humanities 26.2 (1992): 87-102. Web.

Program Overview

STASEL, an acronym for \"Stylistic Treatment at the Sentence Level,\" was a system for teaching style integrating both artificial intelligence and natural language processing techniques (Payette and Hirst 87). Its developers, Julie Payette and Graeme Hirst of the University of Toronto, described it as

an intelligent computer-assisted language instruction system that is designed to teach principals of syntactic style to students of English. Unlike conventional style checkers, the system performs a complete syntactic analysis of its input, and takes the student's stylistic intent into account when providing a diagnosis. (87)

The system was developed C-PROLOG under UNIX (Payette and Hirst 91). STASEL included a syntactic parser, a prototype lexicon, Prolog utilities to handle its string manipulation and I/O functions, a goal-directed style analyzer, and an information module that formed part of the system's output message generation (91). According to Payette and Hirst,

The parser, lexicon, and utility modules serve as a front end for the subsequent stylistic analysis. With the I/O routines of the utility module, the parser reads the input sentence and stores the words in a list structure that is examined from left to right, with backtracking as necessary. (91)

STASEL integrated a number of features that differentiated it from similar experimental or commercial stylistic programs:

• it bases its analysis upon the writer's stylistic intent; that is, the system performs a goal-directed stylistic analysis;
• it is based upon a comprehensive parser that can recognize stylistic features and analyze an important set of English structures[...];
• it generates explicit representations of a sentence's syntactic structure in the form of parse trees, one of which, the stylistic parse tree, is specifically constructed for stylistic analysis and for teaching the mechanics of English sentence construction;
• it is designed for educational purposes and provides a communicative environment where the student can \"learn by doing.\" (Payette and Hirst 88-89)

In keeping with its instructional aims, STASEL was an interactive system capable of accepting full sentences and \"analyz[ing] their lexical, structural and positional characteristics\" (Payette and Hirst 89). It was designed to be extensible, so that additional text and semantic processing capabilities could be incorporated at a later date (89). Payette and Hirst identified expandability as a central motivation for STASEL, as it was their intent \"that the STASEL prototype will form the basis for the development of intelligent tutoring systems for teaching writing\" (Payette and Hirst 100).

Source

Payette, Julie and Graeme Hirst. \"An Intelligent Computer-Assistant for Stylistic Instruction.\" Computers and the Humanities 26.2 (1992): 87-102. Web.