What determines how many exotic resources you get when the bazaar opens for business (i.e., Universal Translator researched)?

As the title says, what determines how many exotic resources you get when the bazaar opens for business (i.e., Universal Translator researched)?  I'm having a hard time correlating the amount of resources available in the bazaar with anything I am doing.  Right now it just seems random, but usually things appear random because you don't understand the algorithm.

thanks!