That's right. The easiest way to see what you will get for a Great Scientist, for instance, would be to go to "Data", "Sort", then choose "Sort by" "Scientist" "Descending", and choose "Then by" "Base Cost" "Ascending." Once you do that, the techs you will get for a Great Scientist will be listed in order. The tech you will get is the first tech listed that you have not researched, but do have the prerequisites to research. Edited due to backwardness.