Cycle frequency in standard Rock-Paper-Scissors games: Evidence from experimental economics

The Rock-Paper-Scissors (RPS) game is a widely used model system in game theory. Evolutionary game theory predicts the existence of persistent cycles in the evolutionary trajectories of the RPS game, but experimental evidence has remained to be rather weak. In this work we performed laboratory experiments on the RPS game and analyzed the social-state evolutionary trajectories of twelve populations of N=6 players. We found strong evidence supporting the existence of persistent cycles. The mean cycling frequency was measured to be $0.029 \pm 0.009$ period per experimental round. Our experimental observations can be quantitatively explained by a simple non-equilibrium model, namely the discrete-time logit dynamical process with a noise parameter. Our work therefore favors the evolutionary game theory over the classical game theory for describing the dynamical behavior of the RPS game.Comment: 7 Page, 3 figure; Keyword: Rock-Paper-Scissors game; cycle; social state; population dynamics; evolutionary trajector

4,4′-Di-3-pyridyl-2,2′-dithio­dipyrimidine

The asymmetric unit of the title compound, C18H12N6S2, contains one half-mol­ecule situated on a twofold rotational axis that passes through the mid-point of the S—S bond. In the mol­ecule, the C—S—S—C torsion angle is 81.33 (7)°. The crystal packing exhibits no significantly short inter­molecular contacts

(S)-1-[3,5-Bis­(trifluoro­meth­yl)phen­yl]-N-methylethyl­amine–(R)-2-hydroxy­butane­dioic acid (1/1)

In the title compound, C11H11F6N·C4H6O5, a key inter­mediate in the synthesis of the NK1 receptor antagonist of casopitant, the F atoms of the trifluoro­methyl groups are disordered over two sites with equal occupancies. In the crystal, the components are linked by bifurcated N—H⋯(O,O) hydrogen bonds