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Detecting Problematic Observer Offsets in Sparse Photometry


Tom Calderwood
1184 NW Mt. Washington Drive, Bend, OR 97701

Received January 20, 2014; revised April 15, 2014; accepted April 23, 2014


A heuristic method, based upon histogram analysis, is presented for detecting offsets pervasive enough to be symptoms of problematic observing technique or calibration. This method is illustrated by a study of scatter in AAVSO photoelectric photometry (PEP) for five well-observed variable stars.

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