updated README.md to better describe the data set.

Author: jooncodes

bob-ross/README.md

@@ -1,3 +1,5 @@
 # Bob Ross
 
 This folder contains data behind the story [A Statistical Analysis of the Work of Bob Ross](https://fivethirtyeight.com/features/a-statistical-analysis-of-the-work-of-bob-ross/).
+
+`elements-by-episode.csv` tracks 67 different elements found in Bob Ross paintings featured in “The Joy of Painting” (S01E01 to S31E13). All values for the elements in the file are **binary**, **1** meaning the element is **present** and **0** meaning the element is **not present**.