2. The principle of equal buying and selling: When a certain number of buying positions are established, the same number of selling positions should also be established, otherwise the mismatch between long positions and short positions will expose the positions (that is, there will be net long positions or short positions) and face greater risks.
3. The principle of opening positions at the same time: generally, long positions and short positions should be established at the same time. In view of the fluctuation of futures prices, trading opportunities are fleeting. If you can't open a position at the same time at a certain moment, the spread may become unfavorable to arbitrage, thus losing the arbitrage opportunity.
4. Principle of simultaneous hedging: When the arbitrage position reaches an expected profit target after a period of fluctuation, it is necessary to settle the profit through hedging, and at the same time, it is also necessary to hedge. Because if hedging is not timely, it is likely to make the long-term spread profit disappear instantly.
5. Contract correlation principle: Arbitrage should generally be conducted between two contracts with strong correlation, but not all varieties (or contracts) can be arbitraged. This is because only when the contract has a strong correlation, the spread will return, that is, the spread will expand (or shrink) to a certain extent, and it will return to the original equilibrium level, so that there is a basis for arbitrage. Otherwise, arbitrage on two unrelated contracts is different from one-way speculation on two different contracts.