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Margot Tollefson is a self-employed consulting statistician residing in the tiny town of Stratford in the corn and soybean fields of north-central Iowa.She started using the S-Plus language in the early 1990s and was happy to switch to R about ten years ago. Margot enjoys writing her own functions in R - to do plots and simulations, as well as to implement custom modeling and use published statistical methods. She earned her graduate degrees in statistics from Iowa State University in Ames, Iowa.