Rweight has a mean of 1.25, a standard deviation of 0.99, but also a 75th percentile of 1.00. This means, as shown in the figure, that the variable is very skewed. In fact, most authors only collaborate one time. However, there are outliers, for example, there is a rweight of 56 in one of the rows, which would mean that these two authors co-authored 56 documents together.