Analyze module quiz

Knowledge check

Pick one answer per question. Explanations appear after you submit.

1. 1. Correlation ≠ causation because:

   • Correlation is weak
   • A third variable or timing may drive both
   • P-values are unreliable
   • Sample was small

2. 2. Two-way ANOVA is used when:

   • One factor, continuous response
   • Two factors, continuous response, with interaction test
   • Two categorical variables
   • Paired samples

3. 3. Chi-square association tests:

   • Two continuous variables
   • Two categorical variables' association
   • Paired means
   • Regression fit

4. 4. RPN uses:

   • Severity + Occurrence + Detection
   • S × O × D
   • Only Severity
   • Only Detection

5. 5. P = 0.03, mean diff = 0.05 mm on ±3 mm tolerance:

   • Significant and important
   • Statistically significant but practically negligible
   • Not significant
   • Reject data

6. 6. A histogram of seam strength shows two peaks. Best move:

   • Fit a normal curve
   • Stratify by machine, material or shift to find the two populations
   • Delete outliers
   • Ignore

7. 7. Before/after data on the same 30 garments is analysed with:

   • Two-sample t
   • Paired t
   • Chi-square
   • One-way ANOVA

8. 8. A cause is confirmed when:

   • Fishbone lists it often
   • Manipulating or removing it changes the Y as predicted
   • The team agrees
   • The sponsor picks it

9. 9. Simple linear regression R² = 0.85 on shrinkage vs cycle time means:

   • Cycle time causes shrinkage
   • Cycle time explains 85% of variation; causation needs mechanism
   • Model is invalid
   • R² should be 1.0

10. 10. You suspect measurement error inflates variation. Correct pre-analysis step:

    • Ignore and continue
    • Repeat MSA and fix the measurement first
    • Increase sample
    • Change test