The context tree weighting method (CTW) is a
lossless compression and prediction algorithm by
Willems, Shtarkov & Tjalkens 1995. The CTW algorithm is among the very few such algorithms that offer both theoretical guarantees and good practical performance (see, e.g.
Begleiter, El-Yaniv & Yona 2004).
The CTW algorithm is an “
ensemble method”, mixing the predictions of many underlying variable order
Markov models, where each such model is constructed using zero-order conditional probability estimators.