Letting Different Views About Business Cycles Compete

There are several candidate explanations for macro-fluctuations. Two of the most common discussed sources are surprise changes in disembodied technology and monetary innovations. Another popular explanation is found under the heading of a preference or more generally a demand shock. More recently two other explanations have been advocated: surprise changes in investment specific technology and news about future technology growth. The aim of this paper is to provide a quantitative assessment of the relative merits of all these explanations by adopting a framework which allows them to compete.