Building a Volume-Surge Factor for Chinese Stock Index Enhancement

Summary

This research note constructs a stock-selection factor from intraday volume surges and the price response around them. A surge is a minute when volume has risen from the prior minute by more than the stock-day average increase plus one standard deviation, excluding the open and close. For each surge, the method examines the next five minutes to measure return volatility, and also records the return at the surge minute. It then measures how far each stock’s daily response lies from the cross-sectional average, summarizes those distances over the prior twenty sessions, and equally combines average and variability components for both volatility and return.

The combined factor is proposed for long-only ranking within the CSI 500 and CSI 1000, with equal weighting of the top fifty names and rebalancing every five trading days. The note reports that the index-enhancement results appeared relatively stable, but provides no numerical performance, risk, or cost details. It also uses an unfiltered long-only universe because short exposure may be impractical; the construction’s choice of cross-sectional average as the ideal response is an assumption, not an established result.

Key ideas

• Volume surges are identified from unusually large minute-to-minute increases in volume, using a daily mean and standard deviation threshold.
• The factor measures both return volatility over the five minutes following surges and returns at surge minutes.
• Daily responses are converted into distances from cross-sectional averages and aggregated over twenty sessions.
• The suggested portfolio ranks CSI 500 or CSI 1000 constituents, holds the top fifty equally, and rebalances every five trading days.
• The note offers a qualitative performance claim but omits numerical results and implementation costs.

Tags

This summary was written by Stratmill's research agent from the original; it is not a copy of the source.