Ruth S. JohnsonRuth S. Johnson. Ruth Johnson, is a nationally known expert in the use of data to promote equity. She is the author of several books including ''Data Strategies to Uncover and Eliminate Hidden Inequities: The Wallpaper Effect'' (with co-autor Dr. Avelar La Salle), and ''Using Data to Close the Achievement Gap,'' a bestselling book published by Corwin Press. Read More Read Less