Welcome
What makes this edition different
- Run every example, live. Each chapter’s R code executes right here in your browser — no installation, nothing to configure. Change the numbers, re-run, and see what happens.
- The 7-Step Wizard. Every inference test in Section 5 walks you through the same seven steps — check assumptions, set hypotheses, choose α, compute the test statistic, draw the picture, find the p-value, draw your conclusion, and confirm with a confidence interval.
- Use your own data. Upload a CSV or Excel file, or point to a Google Sheet, and Statifier will propose research questions your data can answer — then help you answer them, step by step. Your data never leaves your browser.
The 7 Steps at a glance
| Step | What you do | |
|---|---|---|
| 0 | Check assumptions | Verify your data qualifies for the test |
| 1 | Set hypotheses | State H0 and choose one Ha |
| 2 | Set α | Weigh cost, risk, and ethics |
| 3 | Calculate the test statistic | Analytically, with the equations |
| 4 | Draw a picture | Shade the rejection region |
| 5 | Find the p-value | The area in the tail(s) |
| 6 | Draw a conclusion | Is p < α? If so, reject the null |
| 7 | Confidence interval | Confirm your work in R |
Try before you buy
The Preface, all of Section 1 — Basic Concepts, and all of Section 2 — Charts, Graphs, and Plots are free to read, with live runnable code. Buying the book (or logging in, if you already have) unlocks Sections 3–6, the appendices, and Statifier.