Frequencies for first 10,000 rows of enghead_t variable in vindecode dataset : (head configuration) | description | Freq. Percent Cum. -------------------------+----------------------------------- | 4,638 46.38 46.38 Double Overhead Camshaft | 3,135 31.35 77.73 Overhead Valve | 1,005 10.05 87.78 Single Overhead Camshaft | 1,186 11.86 99.64 Unknown | 36 0.36 100.00 -------------------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 22 Oct 2016