The title and the chemical names of the paper by Tabuchi, Takahashi, Gotoh, Akashi & Ishida [Acta Cryst. (2005), E61, o4215-o4217] are corrected.[This corrects the article DOI: 10.1107/S160053680801948X.].

It is shown that for a ‘complex economy’, characterised in terms of a formal dynamical system capable of computation universality, it is impossible to devise an e¤ective theory of policy. JEL Classi…cation Codes: C60, E60, E61, E69

By introducing the concepts of implicit coalitions and con‡ict of interests in a multiple-player context, this paper generalizes some theorems on policy invariance and equilibrium existence and uniqueness for LQ policy games. JEL: C72, E52, E61

The title compound, C(10)H(12)FN(3)S, crystallizes in the same space group (P2(1)/c) as two polymorphic forms of 4-phenyl-1-(propan-2-yl-idene)thio-semicarbazone [Jian et al. (2005). Acta Cryst. E61, o653-o654; Venkatraman et al. (2005). Acta Cryst. E61, o3914-o3916]. The arrangement of mol-ecules relative to the twofold screw axes is similar to that in the crystal structure of the lower densit...

This paper considers political credibility of allocations in settings with dynamic private information. It embeds a benchmark dynamic moral environment into political economy games which feature repeated voting over mechanisms. Optimal politically credible allocations are shown to solve virtual planning problems with social discount factors in excess of the private one. JEL codes: C73, D72, D82...

This paper outlines the evolution of the theory of economic policy from the classical contributions of Frisch, Hansen, Tinbergen and Theil to situations of strategic interaction. Andrew Hughes Hallett has taken an active and relevant part in this evolution, having contributed to both the development and recent rediscovery of the classical theory, with possible relevant applications for model bu...

This paper reformulates the issue of the international coordination of monetary policy in the framework of an extended game with observable delay, where governments are required to set the timing of their respective actions before proceeding to the actual choice of their monetary policies. This allows to shrink signi...cantly the set of equilibria. JEL Classi...cation: D43, E61, F41, F42

Several recent papers have proposed recursive Lagrangian-basedmethods for solving dynamic contracting problems. Thesemethods give rise to Bellman operators that incorporate either a dual inf-sup or a saddle point operation. We give conditions that ensure the Bellman operator implied by a dual recursive formulation is contractive. JEL codes: C61, C73, D82, E61.