Researchers replicate just 13 of 21 social science experiments published in top journals

Joel Achenbach:

The “reproducibility crisis” in science is erupting again. A research project attempted to replicate 21 social science experiments published between 2010 and 2015 in the prestigious journals Science and Nature. Only 13 replication attempts succeeded. The other eight were duds, with no observed effects consistent with the original findings.

The failures do not necessarily mean the original results were erroneous, as the authors of this latest replication effort note. There could have been gremlins of some type in the second try. But the authors also noted that even in the replications that succeeded, the observed effect was on average only about 75 percent as large as the first time around.

The researchers conclude that there is a systematic bias in published findings, “partly due to false positives and partly due to the overestimated effect sizes of true positives.”