Statistical Quality Control Techniques CTEL-TM-OTM Practice Questions (Page 1)

Questions 1–5

1. 1expert · hard

   A test manager needs to estimate the average test case review time across a large organization. The organization has 5,000 test cases, and the manager has time to review only 100. The test cases are stored in a database ordered by creation date. The manager is concerned that older test cases may have different review times than newer ones. Which sampling method is most appropriate to address this concern?

   • AStratified sampling by creation date (e.g., by month or quarter), then random selection within each stratum.
   • BSystematic sampling by selecting every 50th test case.
   • CConvenience sampling of the 100 most recently created test cases.
   • DSimple random sampling of 100 test cases.
   Reveal Solution Discussion Select an answer first
2. 2foundation · easy

   What does a p-value less than the significance level (e.g., 0.05) indicate in a hypothesis test?

   • AThe test data are normally distributed
   • BReject the null hypothesis, suggesting the observed effect is statistically significant
   • CThe alternative hypothesis is proven true
   • DFail to reject the null hypothesis, indicating no evidence of an effect
   Reveal Solution Discussion Select an answer first
4. 3expert · hard

   A test manager is monitoring the defect detection rate using a control chart. The chart shows a sudden spike above the upper control limit in one cycle. The manager investigates and finds that a new tester joined the team that week. What is the most appropriate action?

   • AInvestigate the assignable cause (the new tester) and determine if the process should be adjusted or the tester trained.
   • BConclude the process is not capable and stop testing.
   • CRecalculate the control limits to include the new data point.
   • DIgnore the spike because it is only one point.
   Reveal Solution Discussion Select an answer first
5. 4foundation · easy

   Which visual aid is most effective for showing the trend of a test metric over time?

   • APie chart
   • BLine chart
   • CBar chart
   • DScatter plot
   Reveal Solution Discussion Select an answer first
6. 5application · medium

   A test manager is evaluating whether a test process is stable over time. The manager collects weekly data on test pass rates and plots them on a control chart. The chart shows random variation around the center line with no points outside the control limits. What is the most appropriate conclusion?

   • AThe process is out of control because there is variation.
   • BThe process is capable of meeting specifications.
   • CThe process is out of control because the points are not all on the center line.
   • DThe process is stable and predictable, so no corrective action is needed.
   Reveal Solution Discussion Select an answer first