Margin of Error Media
Margin of Error Media
The quantitative skills every business professional actually needs, explained the way they should have been the first time.
The Books
Five books. Each covers a distinct skill that shows up in business analytics work. Together, they provide the quantitative foundation that most programs spread across disconnected courses, if they cover it at all.
Every book is available to read online for free. Print and digital formats are also available.
Margin of Error
Statistics for a World That Needs Better Decisions
Statistical reasoning without the usual prerequisites. Real stories, real data, real consequences. It builds the intuition that supports clear thinking about data.
Run the Numbers
Data Analysis with R and the Tidyverse
Turn statistical ideas into working code. Data import, wrangling, visualization, and reporting in R, with live code you can run in the browser.
Good Data Starts Here
Survey Design for Business Professionals
A concise guide to writing surveys that produce usable data. Covers question design, measurement, sampling, and the mistakes that quietly ruin results.
Evidence First
Business Research Methods from Problem to Report
The full research toolkit, from problem formulation through analysis and reporting. Written for graduate students and working analysts who need to design credible studies.
Make It Visible
Visual Analytics and Data Storytelling
Communicate what the data says. Interactive visualization, geographic mapping, dashboards, and the ethics of showing data honestly.
Start Here
Not sure where to begin?
If you want to build statistical intuition from the ground up, start with Margin of Error. It covers variation, uncertainty, and inference without assuming calculus or prior coursework.
If you already have a statistics background and need to work in R, start with Run the Numbers.
If you are teaching a course and want to see what is available, visit the Instructor Portal.
Interactive Tools
Each book is paired with interactive applications that let you explore concepts by changing inputs and watching what happens. These are not toys. They are teaching instruments built to make abstract ideas concrete.
Browse the full collection at apps.marginoferrormedia.com.
Sampling Distribution Explorer
Draw repeated samples from a population and watch the sampling distribution build in real time. See how sample size affects the spread of estimates.
Confidence Interval Simulator
Generate hundreds of confidence intervals and see how many capture the true parameter. A direct demonstration of what “95% confidence” actually means.
Regression Playground
Fit regression models to different datasets. Add variables, check residuals, and see how the model changes with each decision.