Abstract: Under the requirement of constructing multi-level capital market, it is the effective derivatives-spots hedging mechanism that contributes to the well-developed financial market in our country. The function of providing risk-hedging for investors under futures-spots system requests more than price and volatility synchronously between them, but at the microscopic level, that is, on the level of order liquidity. The investors such as arbitragers and hedgers under high-frequency circumstances build trading records of stock index future market and spot market together. And whether there is a an arbitrage opportunity, the order liquidity of these two types of assets will change earlier than prices. If in any circumstance, the convergence of order liquidity will be reflected in securities of these two categories, the abnormal basis risk can hardly occur. This makes a contribution to the establishment of healthy "walk-the-dog" effect between stock index and stock index futures. Based on high-frequency trading data of futures and spots, order liquidity has been constructed and an effective method has been provided to test whether there is "walking-the-dog" effect to keep close relation between futures and spots under order liquidity level in usual days. Theorem 1 provides the theoretical foundation of test method in this paper. Volume-clock method is used in high-frequency trading data and dominants to chronic-clock is depicted in this paper. In empirical study, using high-frequency trading data of SS300 index futures and spot index, it's proved that there is closing "walking-dog" relation between index futures and spot index in our market under order liquidity level. It is not easy to achieve a small quantity of profits from high-frequency futures-spot arbitrage by digging high-frequency trading orders. Secondly, the adjustments on changes of stocks' prices imposed by traders' information can be reflected by return measured by trading volume, which is closer to normal distribution than return measured by time.

Key words: futures-spots market, order liquidity, walking-dog effect, volume clock, high frequency data