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Common chart mistakes that mislead people, and how to fix them
Spot and fix common chart crimes: pie overload, 3D distortion, truncated axes, dual-axis tricks, rainbow heatmaps, and wrong chart types. Clear encoding beats decoration.
How to run an experiment review meeting that ends with a decision
Run experiment reviews that decide: ship, iterate, stop, or gather one named fact. Use a short agenda, a one-page pre-read, clear roles, and a written decision log.
Why data teams use separate dev, test, and production environments
Laptop truth is not production truth. Learn what dev, stage, and prod mean for data work, a simple promotion path from notebook to trusted table, secrets hygiene, and…
Goodhart’s law: what happens when a metric becomes a target
Goodhart’s law: when a measure becomes a target, it stops being a good measure. Pair KPIs with incentives, audit gaming paths, and prefer metrics that are hard to…
How to add notes and callouts that make a chart’s point obvious
Treat titles, callouts, reference lines, a so-what line, and footnotes as part of the chart. Annotation turns a clean picture into a decision aid without lying.
