The gold standard's evolution and operation differed in practice from the predictions of economists' theoretical models. The selection from the work of John Maynard Keynes suggests that central banks actually possessed significant policy autonomy under the gold standard owing to the presence of the fluctuation bands which were demarcated by the gold import and export points. Robert Triffin describes other aspects in which the gold standard's operation diverged from the predictions of standard models, emphasizing asymmetries and arguing that the system operated to the benefit of Europe but not the periphery. A.G. Ford documents Triffin's point, contrasting the gold standard's operation in Britain with its effects in Argentina. Barry Eichengreen synthesizes the work of Triffin and Ford, offering evidence from British experience which supports their interpretations of the gold standard. Finally, Jeffry Frieden provides a political-economy analysis of the emergence of the gold standard, emphasizing domestic political factors.