IASSC Certified Lean Six Sigma Black Belt (ICBB) — Question 65

A valid mathematical Regression represents all of the characteristics shown except ___________________________.

Answer options

• A. The residuals when plotted follow a Normal Distribution
• B. The sum of the residuals is zero
• C. All of the standardized residuals will be within ±3 Standard Deviations
• D. Most standardized residuals are within ±2 Standard Deviations

Correct answer: C

Explanation

Option C is incorrect because not all standardized residuals need to fall within ±3 Standard Deviations; while some may, it is not a requirement for a valid regression. Options A, B, and D correctly describe characteristics of a valid regression, including the behavior of residuals.