Home > Glossary > Certified Tester Foundation Level > Error Guessing

📖 What is Error Guessing?

A test technique in which tests are derived on the basis of the tester's knowledge of past failures, or general knowledge of software failure modes. Testers anticipate errors, defects, and failures based on their experience.

🥋 Sensei Says:

"Look for keywords like 'anticipate', 'past failures', or 'tester's intuition' in exam questions referring to Error Guessing."

📚 Certification: Certified Tester Foundation Level (CTFL-v4.0)

🔑 What are the Key Concepts of Error Guessing?

▸ Based on past failures and knowledge
▸ Anticipates specific defects
▸ Relies heavily on tester intuition
▸ Unstructured technique

🎯 How does Error Guessing appear on the CTFL-v4.0 Exam?

Apply error guessing to find common defects like divide-by-zero.

Identify the technique based on 'anticipating defects'.

Use past defect reports to guess errors.

❓ Frequently Asked Questions

Is error guessing structured?

It is generally unstructured and heavily dependent on the tester's skill.

When is it most effective?

After formal techniques have been applied, to catch edge cases.

Related Terms from Certified Tester Foundation Level

Test Control System Testing Test Metric Iterative Development Model Control Flow Graph Branch Coverage

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