TROLL's origins go back to the early days of interactive computing.  In the mid1960's when punch cards and batch processing were state-of-the-art, computer scientists at the Massachusetts Institute of Technology developed CTSS, the Compatible Time-Sharing System.  Edwin Kuh, an economics professor at MIT, realized that the new technology with the right software would let economists develop and test mathematical models without having to write programs in Fortran or a similar language.  Thus was born TROLL, one of the earliest "fourth generation" languages.  The name was derived from an acronym for Time-shared Reactive OnLine Laboratory.  The first version of what we now call "Mainframe TROLL" was released in 1971. 

Since then, TROLL has undergone continual evolution and improvement.  It was used both as a modelling tool and as a testbed for the development of new algorithms and techniques, such as the NL2SOL nonlinear least-squares optimizer, Belsley-Kuh-Welsch regression diagnostics, and LIMO, an application of eigensystem analysis to study the dynamics of simulation models.  Some of that work is described in the References listed below. 

In 1987, MIT licensed to Intex the exclusive right to develop and market TROLL.  Through the 1980s, TROLL was available exclusively on mainframe computers.  By then, personal computers and economical workstation computers had become popular and were powerful enough to run typical TROLL applications.  And some features of TROLL that were ahead of their time in the 1970s were showing their age    for example, Mainframe TROLL limited models to a little over 2000 equations, and some users were bumping into that limit.  In 1991, Intex began an ambitious project to develop a totally new "Portable TROLL" that would provide the major capabilities of Mainframe TROLL while eliminating any size restrictions and would run on whatever types of computer our customers required.  The project was sponsored in part by several Mainframe TROLL licensees, including the Bank of Canada, the Federal Reserve Board of Governors, the International Monetary Fund, the Bank of Norway, and the Commission of the European Community. 

Today, Portable TROLL is available on many different platforms including PCs and various Unix workstations.  Intex and MIT continue to collaborate, and many leading-edge techniques developed at MIT are incorporated into the TROLL system.  TROLL enjoys a loyal following, and one of the benefits that TROLL users appreciate most is the ability to share developments and new techniques with other users.  Intex helps new users feel part of the community through its newsletters, user group meetings, and direct access to the TROLL developers for help or suggestions.

Bibliography of TROLL-Related Research