Christina Majaski writes and edits finance, credit cards, and travel content. She has 14+ years of experience with print and digital publications. Robert Kelly is managing director of XTS Energy LLC, ...

In 1950, John Nash — the mathematician later featured in the book and film “A Beautiful Mind” — wrote a two-page paper that transformed the theory of economics. His crucial, yet utterly simple, idea ...

Nash equilibrium helps predict other investors' moves; no net gain by altering your long-term strategy. A dominant strategy excels regardless of others' actions, aiding investment decisions. Using ...

“All in.” Your opponent slides a stack of chips across the high-stakes poker table. You glance back at your cards, a pair of sixes. The game is Texas Hold’em. Only two of you remain, and no community ...