What analytical point concerning time complicates the retrospective correlation of mood reports with solar activity?

Answer

The lag time between the CME arrival and the onset of the major geomagnetic storm.

Because a CME's impact can take days to arrive, correlating a feeling reported today with a solar flare that occurred 48 hours prior requires precise logging, which is often lacking, leading to fuzzy retrospective correlation.

What analytical point concerning time complicates the retrospective correlation of mood reports with solar activity?
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