Frequencies for first 10,000 rows of hyaline variable in natl2002 dataset : Hyaline | membrane | disease | Freq. Percent Cum. ------------+----------------------------------- 1 | 18 0.18 0.18 2 | 9,613 96.13 96.31 9 | 369 3.69 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 22 Dec 2015