Tetrad is suite of tools educational researchers can use to build visualizations of causal models. It creates, simulates data from, estimates, tests, predicts with and searches for causal and statistical models. The program provides sophisticated methods in a friendly interface requiring very little statistical sophistication of the user and no programming knowledge.
Tetrad is freeware that performs many of the functions in commercial programs such as Netica, Hugin, LISREL, EQS and other programs, and many discovery functions these commercial programs do not perform. It is not intended to replace flexible statistical programming systems such as Matlab, Splus or R.
Learn more: Tetrad