Quality Characteristics for MBT Models CT-MBT Practice Questions (Page 1)

Questions 1–5

1. 1application · medium

   A model-based testing team is reviewing a state machine that models a user session. The model includes states for 'active', 'idle', and 'expired', but the requirements also specify a 'logged out' state that can be reached from any state. The model does not include this state. Which quality characteristic is most directly affected?

   • ACorrectness — the 'idle' state is incorrectly modeled because it should transition to 'logged out'.
   • BMaintainability — the model is too complex because it has too many states.
   • CCompleteness — the model is missing a required state and its associated transitions.
   • DConsistency — the 'expired' state conflicts with the 'logged out' state.
   Reveal Solution Discussion Select an answer first
2. 2expert · hard

   A team is assessing the quality of a large decision-table model. They have limited budget and need to identify the most critical defects first. Which assessment strategy is most effective for prioritizing defects?

   • ARandomly sample 10% of the rules and assess them in detail.
   • BUse a risk-based approach: first check rules that cover high-impact business functions, then check lower-risk areas.
   • CPerform a complete formal inspection of every rule in the table.
   • DRun an automated tool that checks for syntactic errors only.
   Reveal Solution Discussion Select an answer first
4. 3expert · hard

   A team has a state machine model that is correct and complete but has a very high number of transitions, making it hard to review. The team wants to improve maintainability while preserving the model's behavior. Which refactoring technique is most appropriate?

   • AReplace the state machine with a decision table to reduce the number of elements.
   • BRemove all transitions that are not directly triggered by external events.
   • CMerge all states into a single state with self-transitions.
   • DIntroduce composite states to group related transitions and reduce the number of top-level transitions.
   Reveal Solution Discussion Select an answer first
5. 4application · medium

   A team maintains a state-machine model of a login workflow. A reviewer notices that the model has a transition for 'successful login' and 'invalid password', but no transition for 'account locked'. The team is about to generate test cases from this model. Which quality characteristic is most directly compromised, and what is the most appropriate first action?

   • ACorrectness — change the 'successful login' transition to also handle the locked-account case.
   • BConsistency — remove the 'invalid password' transition because it conflicts with the 'account locked' state.
   • CCompleteness — add the missing 'account locked' transition and its associated guard and actions before generating tests.
   • DMaintainability — refactor the model to use a sub-state machine for all authentication outcomes.
   Reveal Solution Discussion Select an answer first
6. 5application · medium

   A test architect has created a decision-table model for a discount calculation. Before using it for test generation, she wants to assess whether the model correctly reflects the business rules. Which assessment technique is most appropriate for this purpose?

   • AReview the model against the original business rules specification with the business analyst.
   • BGenerate a small sample of test cases and execute them against the current system.
   • CRun a coverage analysis tool to measure how many of the model's rules are reachable.
   • DCheck the model for syntactic correctness using a model parser.
   Reveal Solution Discussion Select an answer first