nrg89

I'm an engineer, so you have to excuse me if this question is focused on math. I'm interested in any equations for these kinds of comparisons in economics because I've been googling forever. Here goes. Two people, A and B, are doing two completely different tasks. A already has the value "a" which measures her aptitude of performing tasks in general and B has the value "b" which measures the same thing for him respectively (lets call these two values "aptitude scores"). A succeeds at her tasks while the majority of people with the same aptitude scores fail, and b fails his task while the majority of people with the same aptitude scores succeed. How will the aptitude scores change? And can we also, based on these results, assign a "difficulty score" to these tasks? Are there any equations that adresses this problem? Where can I learn more about them? While I am looking for a solution to this problem I would also like to know where I could learn more. I'm thankful for all the help I can get!