BACKGROUND:

With the advent of quasi-likelihood, generalized estimating equations, and new ways to handle missing data, has come a striking increase in applicable models, perhaps more than after the 1972 introduction of the Cox model for survival data. TI provided a way to analyze the data.

DESIGN NARRATIVE:

TIl provided graphics for data exploration and model validation. TI ran under most current version of Windows, used Civilized Software's MLAB as its programming language, offered context-sensitive help, a dictionary of relevant terms, identification of file entries from their screen position, and simple animation. TI permitted the user to analyze time-varying data from the two perspectives of repeated measured using a variety of models and time series where both time and frequency domain tools were provided.