Replication and the reproducibility of results are at least as problematic in econometrics as the sociologist Harry Collins has shown them to be in the natural sciences. A later test will often contradict an earlier one see the extensive lists of examples in Goldfarb's 1995 and 1997 papers. In that situation, there may be no a priori way of knowing whether the original test was at fault, whether the new one is incompetent, or whether the discrepancy is to be explained by historical and geographical variation or other differences in the economic processes being studied.

Donald MacKenzie, An Engine, Not a Camera, loc. 108