CTFL_Syll2018 Exam Dumps : ISTQB Certified Tester Foundation Level (Syllabus 2018)

Work Breakdown Structure (WBS) is a project management technique that decomposes a project into smaller and manageable tasks. It is not a factor that is used as a basis for estimating testing effort, but rather an outcome of the estimation process. The other options are factors that can influence the testing effort, such as the quality of the test basis, the requirements for documentation, and the skills of the test team.

References: Section 2.3, Section 2.4

Test metrics are quantitative measures that are used to monitor, control, and improve the test process and its outcomes. Test metrics can be collected at different levels of testing (test case, test suite, test project, etc.) and can be used for different purposes (planning, estimation, execution, evaluation, etc.). Some examples of common test metrics are:

• Percentage of work done in test environment creation: This metric indicates how much effort has been spent on setting up and maintaining the test environment, which includes hardware, software, network, data, tools, etc., that are required for conducting the test activities.
• Number of test cases run: This metric indicates how many test cases have been executed during a given period or phase of testing.
• Deviation from test milestone dates: This metric indicates how much delay or ahead of schedule the test activities are compared to the planned dates.
• Defect density: This metric indicates how many defects have been found per unit of size or functionality of the system under test.

Average number of expected defects per requirement is not a common test metric because it is not easy to estimate or measure how many defects are likely to be found for each requirement. Moreover, this metric does not provide useful information for improving the test process or evaluating the test results. You can find more information about test metrics in A Study Guide to the ISTQB® Foundation Level 2018 Syllabus, Chapter 5, Section 5.41.

Regression testing is a type of testing that is performed after a software system has been changed or modified to verify that the changes have not introduced any new defects or adversely affected the existing functionality of the system. Regression testing can be performed when the software system undergoes different types of changes, such as:

• Corrective changes: Changes that fix defects or errors in the software system
• Adaptive changes: Changes that adapt the software system to new platforms or environments
• Perfective changes: Changes that improve the performance or usability of the software system
• Preventive changes: Changes that avoid potential problems or issues in the software system

In this case, the software system was re-deployed because the backend database was changed from one vendor to another, which is an example of an adaptive change. Therefore, the test manager decided to perform some functional tests on the re-deployed system to ensure that the change did not affect the functionality of the system. This is an example of regression testing.

The other types of testing mentioned in the question are not relevant for this scenario. For example:

• Non-functional testing: This type of testing verifies the non-functional aspects of the software system, such as reliability, performance, security, usability, etc.
• Structural testing: This type of testing verifies the internal structure or implementation of the software system, such as code, architecture, design, etc.
• Unit testing: This type of testing verifies individual components or units of software in isolation from other components or systems.

You can find more information about regression testing in [A Study Guide to the ISTQB® Foundation Level 2018 Syllabus], Chapter 2, Section 2.4.