In the algorithm environment I'm initializing my custom factor with "Filters.QTradableStocksUS() & Filters.Q3000US()". Then the backtester tells me on the first tab:
"Tradable Universe : No / To be eligible for the contest, algorithms must trade within the Quantopian Tradable Universe"
How is that check carried out exactly? I'm using QTradableStocksUS because I don't want to worry about this.