A CLOSER LOOK
The Open Textbook Library records Introductory Statistics as a 2012 Saylor Foundation book by Douglas S. Shafer and Zhiyi Zhang. Shafer taught mathematics and introductory statistics at the University of North Carolina at Charlotte; Zhang taught mathematics there and worked on statistical problems for industry and government.
The authors built the book for a realistic one-semester course. Its sequence starts with descriptive statistics, develops probability and sampling distributions, and then moves into inference and model building. The library record emphasizes a deliberate focus on core material, supported by exercises after each concept rather than a large collection of peripheral topics.
Large-data-set exercises ask students to use statistical software where hand calculation stops being practical. That matters because an introductory result is more than a number: the data source, study design, assumptions, and chosen model determine what the result can mean. The book also includes solutions material written by the authors to keep the exercises aligned with the presentation.
The library lists the textbook under an Attribution-NonCommercial-ShareAlike license and links free online and downloadable formats. Reviews in the same record note limitations worth keeping in view: several examples are centered on the United States, and the approach gives less attention to simulation-based teaching or statistics embedded in current scientific investigations. Those reviews describe classroom usefulness; they do not replace the license or the textbook itself.
