A re‐examination of the q theory of investment using u.s. firm data
用美国企业数据检验托宾q投资模型，发现加总数据会导致动态设定错误的假象并高估调整成本，不完全竞争也会影响部分企业的投资行为。
Abstract Investment models based on Tobin's q are theoretically appealing, but they have been an empirical disappointment when applied to aggregate time‐series data. This paper explores two potential explanations for the poor empirical performance of q investment models, problems arising from aggregation and imperfect competition. The results suggest that aggregation is responsible for spurious evidence of dynamic misspecification and at least partially responsible for an upward bias in estimated adjustment costs. The evidence also suggests that imperfect competition in output markets may have an effect on the investment behaviour of some firms.