A lot of people have attempted to build indicator that assesses if there is a trend going on or the market is ranging. One of them was Mark Jurik too.
This is his version of fractal dimension. Version from Mark Jurik is much smoother than the others but the general rule is the same: it is not a directional indicator, but is attempting to determine if there is a trend in the current market price changes or not, and it should be used bearing that in mind.