The results of the study suggest that the data doesn't fit a Bell curve at all. No matter what end you're talking about. The data fits a power curve.
The authors reveal the software they use and say it works with excel.
"Results reported in Table 1 show that the Paretian distribution yielded a superior fit than the Gaussian distribution in every one of the 54 scientific fields. Recall that a larger chisquare value indicates worse fit and, thus, can be considered an index of badness of fit. As Table 1 shows, the average misfit for the Paretian distribution was 23,888 whereas the misfit of the normal distribution was larger than fortyfour trillion (i.e., 44,199,201,241,681)—a difference in favor of the Paretian distribution in the order of 1:1.9 billion. Figure 2a displays a histogram of the empirically observed performance distribution of researchers. To interpret these results further, consider the field of Agriculture (see Table 1). A normal distribution and a sample size of 25,006 would lead to approximately 35 scholars with more than 9.5 publications (three standard deviations above the mean). In contrast, our data include 460 scholars with 10 or more publications. In other words, the normal distribution underestimates the number of extreme events and does not describe the actual distribution well."
