Broker Spread Emulation

 

I am investigating if it is possible to write mql code to emulate spread changes in the MT4 Strategy Tester.

I assume that Brokers do not manually change spread values and the spread is automatically calculated on the server as trading parameters change.


How do Brokers calculate currency pair market liquidity, volatility and volume?

How do Brokers calculate currency pair spread as liquidity, volatility and volume changes?


Are there generic rules and/or formulae Brokers use to set variable spreads?

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