Just a little experimental stuff. Here's a Random walk index indicator that is using absolute error instead of High low range to construct the index. The results are different but good or bad that would require testing. It produces some big spikes(maybe root squaring values can also prevent that) so a maximum level is set to prevent display issue. As said it's just an experiment an can be improved by mathematical thinkers.

PS: For the Smoothed version, please see: Random Walk Index Smoothed for MT4.