2. Generally speaking, the margin ratio cannot be changed at will, but in the rules of the game stipulated by the exchange, there is usually a sentence "In case of major events or when necessary, the trading ownership will adjust the margin ratio of related varieties". Therefore, it is always said that the party who formulates the rules of the game, since it wants to participate, should not be too serious, but should understand the rules of the game and try to avoid unsystematic risks. (Generally, when the price fluctuates abnormally, the exchange will adjust the margin.
3.
Because futures and spot are very similar except for the duration (in other words, futures can be regarded as the brothers of spot), their judgments should be roughly the same.
And generally speaking, the linkage between the two will be very strong. Of course, in different markets, some varieties will deviate in the short term for some unknown reasons, but this just provides us with arbitrage space.
4. gold T+D spot.
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