How complicated does the model have to be?
批评了因缺乏微观基础而失宠的简单宏观模型（如IS-LM），指出基于微观基础的复杂模型未必更准确，而简单模型在实用中更便捷，不应被淘汰。
Simple macroeconomic models based on IS-LM have become unfashionable because of their lack of micro-foundations, and are in danger of being effectively forgotten by the profession. Yet while thinking about micro-foundations is a productive enterprise, complex models based on such foundations are not necessarily more accurate than simple, ad-hoc models. Three decades of attempts to base aggregate supply on rational behaviour have not displaced the Phillips curve; inter-temporal models of consumption do not offer reliable predictions about aggregate demand. Meanwhile, the ease of use of small models makes them superior for many practical applications. So we should not allow them to be driven out of circulation. Copyright 2000 by Oxford University Press.