A Preliminary Study of the Relationship between the h-Index and Excess Citations

This article presents a study of the average number of excess citations of papers in the h-core, denoted as e(2)/h and the ratio between the e-area and the h-area, denoted as e(2)/h(2). Real-world citation data from different countries are studied. It is found that at the country level, a small set of publications generate a disproportionately large amount of citations. Although different countries have different e(2)/h(2) values in different fields, average e(2)/h(2) values are all above 1. The e(2)/h values vary widely between fields, reflecting the general citation density in these fields. For cumulative data e(2)/h(2) and e(2)/h values each converge quickly. Neither a shifted Zipf nor an exponential model could fit the data.