Forex Strategy Builder performs backtest of a strategy using historical bar data. It calculates each bar starting from the oldest one and finishes with the newest bar. The program interpolates every single bar using a special interpolation algorithm chosen by the user. The interpolation method serves to designate a route that the market price follows inside a bar.
FSB knows four facts about that route;
FSB doesn't know:
We mark a bar “ambiguous” when the backtester cannot decide for sure in what sequence to execute the orders.