Significance & ErrorsWhat p < 0.05 means, and the two kinds of mistake.PsychologyThe decision against the truth.Null is trueNull is falseReject nullType I error (α)Correct — powerRetain nullCorrectType II error (β)Power = 1 − β, conventionally targeted at 0.80. Underpowered studiesare the main reason findings fail to replicate.Significance & Errorslearnposters.com
Significance & Errors — printable life science wall chart from LearnPosters. Free vector PDF, US Letter and A4.

What’s on the Significance & Errors poster

A 2-row table: Null is true · Null is false.

The decision against the truth.

Power = 1 − β, conventionally targeted at 0.80. Underpowered studies are the main reason findings fail to replicate.

Questions about the Significance & Errors poster

What’s on the Significance & Errors poster?
A 2-row table: Null is true · Null is false. The decision against the truth. Reject null — Type I error (α) — Correct — power; Retain null — Correct — Type II error (β). Power = 1 − β, conventionally targeted at 0.80. Underpowered studies are the main reason findings fail to replicate.
Who is the Significance & Errors poster for?
Significance & Errors belongs to the Psychology section rather than to a school year, because life science is not something one grade owns. Anyone learning methods & statistics can pin it up — a beginner, a student mid-course, or someone revising years later.
When should you use the Significance & Errors poster?
Type I is a false positive. Type II is a false negative. Reducing one raises the other. A wall chart earns its place by being glanceable from where the work is happening, so Significance & Errors belongs on the wall where that life science work actually happens, within glancing distance, rather than filed away.
What other posters go with Significance & Errors?
Choosing a Test, Descriptive Statistics and Research Ethics sit alongside Significance & Errors in the Psychology section. Printed together they make a wall rather than a single sheet, which is how a reference set actually gets used.Choosing a TestDescriptive StatisticsResearch Ethics
Is the Significance & Errors poster free to download and print?
Yes. Significance & Errors downloads as a free PDF with no account, no email and no watermark, like everything else in the Psychology section. Print as many copies as you like for a home, a classroom, a library or a tutoring group; reselling the file is the only thing the licence rules out.Read the licence
What size does the Significance & Errors poster print at?
Significance & Errors is a vector PDF laid out for US Letter, and prints on A4 with Fit to page — the same file, no separate download. Because every mark on it is drawn rather than photographed, it stays sharp enlarged to A3, A2 or A1 at a copy shop. Colour carries emphasis only, so a greyscale print of Significance & Errors loses nothing.Printing guide

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