Isabella Velásquez Author

Stephanie Zimmer, PhD, is a senior survey statistician with 10 years experience in survey sampling and design, survey weighting and analysis, and data management. She is an expert statistical programmer in R, SAS, and SUDAAN. She earned her PhD in Statistics from Iowa State University and her BS in Statistics from NC State. After earning the RStudio Tidyverse Trainer certification, she co-taught two courses on tidy survey analysis in R. She is currently a Senior Research Statistician at RTI International.

Rebecca J. Powell, PhD, is a research survey methodologist at RTI International. Her research interests focus on visual design of questionnaires and contact materials. Dr. Powell is a Certified RStudio Tidyverse Trainer and has taught courses and webinars on data management in R and tidy survey analysis in R at both AAPOR and MAPOR. She has a PhD in Survey Research and Methodology from the University of Nebraska-Lincoln and a BS and MS in Applied Statistics from Rochester Institute of Technology.

Isabella Velásquez is a content strategist, data enthusiast, and author. Her experience spans data collection, grantmaking, strategy development, and survey instrument development. She earned her MSc in Analytics and BA in Economics and East Asian Languages and Civilizations from the University of Chicago. She currently works as a Sr. Product Marketing Manager at Posit Software, PBC.