JazzMando What's New - Most mandolinists will rely on experience and feel when landing on that "just right" set of strings, especially when it comes to gauges. Still there are solid principles and even math to help you get it right. Heavy or light. Nickel or Bronze.
Wait. Math? Nobody said there'd be math...
(F0 + Fp) = k(x0 + xp)
Ian Weston, repair tech and luthier of Canada's "Weston Instruments" has a terrific resource available on his website, offering definitive information on factors you'll want to consider if you over take a more calculated to the hunt for new strings. He mentions specifically action, output (electric), artificial harmonics, sustain, and picking speed that will vary with the results of string gauge and construction.
Read Link: String Gauges
Take the time to read up his thoughts in his April 2012 entry, "String Gauges." While you're there, take a look at some of his growing body of electric mandolin eye-candy