We compare the finite sample behaviour of various unit root tests for micro panels where the number of individuals is typically large, but the number of time periods is often very small. As in this case some econometric estimators do not identify the parameters of interest when the processes are...

In this paper we consider the properties of a simple test of parameter restrictions based on standard two-step efficient GMM estimators. The test is computed simply as the difference between the minimised values of the GMM criterion function in the restricted and unrestricted models. We compare...

We compare the finite sample performance of a range of tests of linear restrictions for linear panel data models estimated using the generalized method of moments (GMM). These include standard asymptotic Wald tests based on one-step and two-step GMM estimators; two bootstrapped versions of these...

This paper tests for the importance of cash flow on investment in fixed capital and R&D using firm-level panel data in two countries between 1985 and 1994. For German firms, cash flow is not informative in simple econometric models of fixed investment or R&D. In identical specifications for...

This paper tests for the importance of cash flow on investment in fixed capital and R&D using firm-level panel data in two countries between 1985 and 1994. For German firms, cash flow is not informative in simple econometric models of fixed investment or R&D. In identical specifications for...

Based on the best available theory and evidence, the Mirrlees Review sets out a comprehensive set of proposals for tax reform. While focused on the UK, its analysis and conclusions bear directly on the policy debate in other developed countries. The Review proposes a move to a more neutral tax...

This paper tests for the importance of cash flow on investment in fixed capital and R&D using firm-level panel data in two countries between 1985 and 1994. For German firms, cash flow is not informative in simple econometric models of fixed investment or R&D. In identical specifications for...

This paper analyzes differences in R&D spending and in the impact of R&D on productivity between German and UK firms. We confirm that German firms spend significantly larger amounts on R&D than their UK counterparts, even after controlling for firm size and industry effects. Using a dynamic...