Skip to content
Part CCSIR NET December 2025the-defining-contrasts-are-the-orthogonal-complement-of-the-principal-block-not-the-principal-block-itself

The defining contrasts are the orthogonal complement of the principal block not the principal block itself

Consider the following 25−2^{5}-factorial design with 8 blocks (Block 1: (1), acd, bce, abde; Block 2: e, acde, bc, abd; and six further blocks). Which of the following statements are true?

  1. A.ABC is confounded with blocks✓
  2. B.BCD is confounded with blocks✓
  3. C.CDE is confounded with blocks✓
  4. D.ABDE is confounded with blocks✓

You have the answer. Trap Analysis is why the other three were written.

Not a worked solution repeated four times — the specific reasoning error each wrong option was built to reward.

See pricing

50 are analysed free — try those first.

More on this topic

The chapter behind this: Design of experiments essentials — free to read

From Sampling and Design of Experiments › CRD, RBD, LSD essentials

Last revised . Found a mistake? Tell us — corrections are the fastest thing we act on.

ShareWhatsAppTelegram