A robust test is defined as:

A robust test is defined as:

• A. A test that assumes normality and equal variances.
• B. A term applied to a family of procedures to estimate statistics that are reliable even when the normal assumptions of the statistic are not met.
• C. A nonparametric test for ordinal data.
• D. A parametric test robust to homogeneity violations.

Answer: (B)

Robust tests are designed to perform well even when data don’t meet the strict assumptions of normality and equal variances. In practice, this means a family of procedures whose estimates and inferences stay reliable under a wider range of conditions, using methods that reduce sensitivity to outliers or deviations from the distribution. The option that best captures this idea describes a robust test as a set of procedures to estimate statistics that remain reliable when the normal assumptions aren’t met. The other descriptions either rely on those assumptions, refer to nonparametric tests for ordinal data, or describe robustness in a narrower sense, which doesn’t match the standard definition.

Robust tests are designed to perform well even when data don’t meet the strict assumptions of normality and equal variances. In practice, this means a family of procedures whose estimates and inferences stay reliable under a wider range of conditions, using methods that reduce sensitivity to outliers or deviations from the distribution. The option that best captures this idea describes a robust test as a set of procedures to estimate statistics that remain reliable when the normal assumptions aren’t met. The other descriptions either rely on those assumptions, refer to nonparametric tests for ordinal data, or describe robustness in a narrower sense, which doesn’t match the standard definition.