A data frame with 30 observations on the following 2 variables:
states (a factor with levels AR, CA, CO, DE, GA, ID, IL, IN, KS, KY, MD, MI, MO, MS, MT, NC, NE, NY, OH, OK, OR, Other, PA, SC, SD, TN, TX, VA, WA, and WI)
acres (wheat surface area measured in thousands of acres)
References
Ugarte, M. D., Militino, A. F., and Arnholt, A. T. 2015. Probability and Statistics with R, Second Edition. Chapman & Hall / CRC.