Sandra L. Arlinghaus, PhD, is a mathematical geographer. She holds a PhD in geography from the University of Michigan and has PhD-level training in pure mathematics from the University of Chicago (algebra), the University of Toronto (geometry), and Wayne State University (graph theory). Dr. Arlinghaus has published over 400 books and articles, many in peer-reviewed publications. She is currently Adjunct Professor, School for Environment and Sustainability, University of Michigan, Ann Arbor.

Joseph J. Kerski, PhD, is a geographer, educator, and GIS professional who has served in four major sectors of society: government, academia, private industry, and nonprofit organizations. His career focus is the implementation and effectiveness of geotechnologies across all learning domains. Dr. Kerski holds three degrees, all in geography, and has worked extensively with those in career and technology education, earth and environmental science, geography, history, and mathematics.

William C. Arlinghaus, PhD, holds a PhD in pure mathematics and is Professor Emeritus of Mathematics and Computer Science at Lawrence Technological University, Southfield, Michigan. He has taught all levels of undergraduate university mathematics and computer science and has extensive administrative experience, including service as Department Chair. In total, he has published over 50 books and articles in the USA and abroad.

1. Classifying Numbers and the Distributive Law. 2. Fractions and Decimals. 3. Simple Relational Measures and Measures of Central Tendency and Variation. 4. Earth Measurement: Coordinate Systems and Trigonometry. 5. Data, Variables, and Thematic Maps. 6. Mathematics' Foundations: Set Theory and Algebra. 7. Mathematics' Foundations: Dimension and Geometry. 8. Proximity and Adjacency: Measurement. 9. Measuring Hierarchies and Patterns.