HARK-ing
Hypothesizing After the Results are Known.
What it is
HARK-ing is writing your paper as if you predicted the result you found — even though you actually found it by exploration. Hypothesis 'we predicted X' was added after seeing X in the data. This converts post-hoc observation into apparent confirmatory science, and inflates the perceived evidence for the claim.
Why a reviewer cares
Reviewers look for predictions that are suspiciously specific — exactly the result you got, with no acknowledgement of alternatives. Multiple predictions all confirmed in the same direction. The absence of a pre-registration when one would have been easy to obtain.
How to fix it
Pre-register predictions before collecting or analysing the data. When something interesting emerges from exploration, label it 'exploratory' in the paper and frame it as hypothesis-generating, not hypothesis-confirming. Some venues now accept Registered Reports — peer-reviewed protocols accepted in principle before data collection.
This is one of ~15 canonical methodology explainers Paper Review's red-team report links to. To get a full review of your manuscript, start a Paper Review — $5.