Table 2. Model parameters for full open access dataset.

The various variables included as predictor variables are listed along with random variables in the statistical model of the full dataset. In the “Matched Analysis”, an additional random variable of “volume and issue” was included and the records were subset to only include volumes/issues with both OA and closed access articles. Finally, in the third “APC analysis” model, the predictor variable of APC was added and articles were subset to only include hybrid gold where authors paid an APC, thus removing the predictor of access type. All models shared the same response variable of Citation Counts.

Predictor variables	Response variable	Response variable
Access type	Field	Citation counts
Author count	Journal in field
Journal citation reports (JCR) quartile
JCR article influence score
Year