COMPARISON OF H-INDEX FOR HYDROGEOLOGY LITERATURE FOR MEINZER AWARDEES AND SAMPLE OF FACULTY MEMBERS OF THE GSA HYDROGEOLOGY DIVISION

The h-index is a measure of both publication productivity and significance of a scientist’s published body of work and refers to an “h” number of publications that have been cited at least an “h” number of times. The h-index is known to differ between scientific disciplines because, for example, some disciplines tend to have a longer list of co-authors on publications and longer reference lists, which can yield a higher h-index. Hydrogeologists and university deans and department chairs might want to know the typical h-index for university hydrogeology faculty for comparative purposes.

Two sample populations were used to define the typical h-index of hydrogeologists: (1) Meinzer Awardees (MA), recognized by the GSA Hydrogeology Division (HD) since 1965 as authors of publications that have significantly advanced the science of hydrogeology, and (2) a randomly selected sample of 52 of the ~206 HD members who are in a university faculty. Annual publication citations were downloaded from the Web of Science (WOS), along with WOS values for total citations and h-index for 2010. An annual h-index was calculated for 1965-2010; the 2010 calculated h-index was checked against the WOS value. Whether these are accurate estimates of h-index remains to be further evaluated in terms of WOS data quality. The WOS only goes back to 1965; the h-index of MA who had publications cited before 1980 most likely is undersampled. Data quality issues include but are not limited to whether (a) all citations in various journals are found consistently by author name and (b) cited hydrogeology publications in State and Federal non-journal reports are found in WOS or other data bases.

The average h-index is ~17 for the MA group at the time of their award and ~9 for the HD group in 2010; the difference is statistically significant. Each group has two trends in h-index growth rate; the most productive MA appear to have a higher annual rate of h-index growth than the most productive of the HD faculty sample. For both MA and the HD samples, h-index increases non-linearly with increasing number of cited publications. The slope and intercept of the relation appear the same for both MA and the HD samples, suggesting that both groups have the same citation efficiency.