How to consider fractional counting and field normalization in the statistical modeling of bibliometric data: A multilevel Poisson regression approach

•Fractional counting and field normalization are indispensable in bibliometrics.•Multilevel Poisson regression provides statistical models for the two procedures.•Fractional counting I simulates the usual numerical procedures statistically.•In addition fractional counting II avoids publication duplicates in the data.•Fractional counting II does not depend anymore on the type of fractional counting.