| Abstract: | The purpose of this paper is to explore the relevance of Tobin's ‘q theory’ of investment in explaining aggregate investment in Australia, over the period from December 1966 to December 1986. Using standard capital stock data, the q theory performs poorly. However, the cost of adjustment model implies that the conventional capital stock data need to be revised to allow for these adjustment costs. Once this is done, it is found that the q theory explains a statistically significant (although small) proportion of the movements in aggregate investment The residual behaviour of investment is well explained by an accelerator model |
