A recent news story underscores the importance of basic replication (as well as scholarly attention to detail) for empiricists.
"His [Thomas Herndon's] professors at the University of Massachusetts-Amherst had set his graduate class an assignment--pick an economics paper and see if you can replicate the results. It's a good exercise for aspiring researchers. Thomas chose Growth in a Time of Debt. It was getting a lot of attention, but intuitively, he says, he was dubious about its findings."
Turns out that the grad student's intuition was dead-on as core results from the influential economics article--authored by two leading Harvard economists--could not be replicated. Herndon's replication efforts uncovered a basic error in the spreadsheet. "The Harvard professors had accidentally only included 15 of the 20 countries under analysis in their key calculation (of average GDP growth in countries with high public debt). Australia, Austria, Belgium, Canada and Denmark were missing." In addition, other data for some countries were missing altogether.