Robustness defines the ability of the numerical method to provide a solution despite variabilities in the initial solution and control parameters. This incorporates issues of fault tolerance. Generally, robustness is achieved at the expense of accuracy.

The capacity to remain unaffected by small but deliberate variations in method parameters and provide an indication of its reliability.

The ability of a system to remain stable over a large range if changes in system inputs (loads and set points).

the degree to which a system or component can function correctly in the presence of invalid inputs or stressful environment conditions [ IEEE 90].

(1) a user-oriented quality requirement specifying the degree to which an application shall continue to function properly under abnormal circumstances. (2) a quantitative quality factor measuring the actual degree to which an application continues to properly function under abnormal circumstances. For example, robustness includes the proper handling (e.g., failover, degraded modes of operation, and disaster recovery) of: Invalid input, either by human actors or other applications. Failure of hardware components. Failure of software components. Failure of external systems on which the system depends. Contrast with operational availability and reliability.

The condition of a product or process design that remains relatively stable with a minimum of variation even though factors that influence operations or usage, such as environment and wear, are constantly changing.

Dependability of a system, product, or process to continue operating well even though conditions are constantly changing.