Before revision:  The approximate HTPGM achieves up to 3 orders of magnitude speedup compared to the baselines and consumes significantly less memory, while obtaining high accuracy compared to the exact HTPGM.
After revision:  The approximate HTPGM achieves up to 2 orders of magnitude speedup compared to the baselines and consumes significantly less memory, while obtaining high accuracy compared to the exact HTPGM.