I — Datum

Engineering Notes
Practical guides on statistical analysis, process control, quality engineering, and continuous improvement. Written from floor-level experience.
Ref: AIAG · Montgomery · ISO 22514-2

II — Bulletin Index

# Title Published
1 Minitab Alternatives in 2026: What Your Options Actually Look Like Comparing Minitab alternatives for statistical analysis and SPC. An honest look at JMP, R, Python, and cloud-based options.
2 Quality Tools Shouldn't Cost More Than the Problems They Solve Minitab costs $2,594/year. A quality engineer in Nairobi earns $12,000. Purchasing power pricing fixes this.
3 Bayesian SPC: What Your Control Charts Aren't Telling You Traditional SPC uses fixed control limits from the 1920s. Bayesian SPC adapts, detects changepoints, and quantifies uncertainty.
4 Your Quality Team Has Hypotheses. They Just Don't Track Them. Quality engineers form hypotheses every day but track none of them. Structured hypothesis management changes how teams learn.
5 DOE for Beginners: Running Your First Designed Experiment A beginner-friendly guide to Design of Experiments (DOE). Learn how to plan, run, and analyze your first factorial experiment without the textbook jargon.
6 Gage R&R: What It Is, How to Run One, and What the Numbers Mean A practical guide to Gage R&R studies. Learn how to assess your measurement system, interpret %GRR, and decide if your gages are good enough.
7 Your Cpk Is a Point Estimate. That Should Terrify You. Your Cpk is a sample estimate with hidden uncertainty. Bayesian Cpk gives you P(Cpk > 1.33) with credible intervals. Free calculator included.
8 How to Read a Control Chart (Without Second-Guessing Yourself) A practical guide to reading SPC control charts. Learn the Western Electric rules, common signals, and what to actually do when a point goes out of control.
9 Beyond ±3σ: Conformal Prediction for Process Monitoring Distribution-free control limits with guaranteed false alarm rates. No normality assumption. First commercial implementation.
10 Leadership as Failure Mode: An RCA of Why Operational Excellence Programs Die "Leadership commitment" isn't a root cause. It's where lazy RCA stops. Here's the fault tree for why your CI program actually died.
11 Cpk vs Ppk: What's the Difference and When to Use Each Learn the real difference between Cpk and Ppk capability indices, when to use each, and common mistakes engineers make interpreting them.