WGU C207 Data-Driven Decision Making Complete Study Guide 2026/2027 Essential Certification Manual: Comprehensive Topic Review, Realistic Practice Questions, and Full Test Bank

A questionnaire claims to measure employee engagement, but most of its items ask only about salary satisfaction. What is the study’s most serious weakness? A. Poor construct validity B. Excessive statistical power C. High external validity D. Random measurement error Correct Answer: A. Poor construct validity Rationale: Construct validity concerns whether an instrument accurately measures the concept it claims to measure. Salary satisfaction is only one possible component of engagement, so the questionnaire may not represent the full construct. Statistical power concerns the ability to detect effects. External validity concerns generalizability. Random error produces unpredictable variation but does not explain a systematic mismatch between the construct and its measurement. Question 2 A university wants to estimate student satisfaction across 40,000 learners. Which sampling plan would provide the strongest foundation for statistical inference? A. Survey the first 20 students entering the library B. Survey only students who volunteer online C. Select an adequately sized random sample D. Interview the student-government leadership team Correct Answer: C. Select an adequately sized random sample Rationale: A statistically useful sample should be sufficiently large and selected through a probability-based method so that members of the population have a known chance of inclusion. Convenience samples, volunteer samples, and leadership groups may systematically differ from the larger student population. A large sample alone cannot correct a biased selection method, while randomization supports representativeness and valid inference. Question 3 A digital scale consistently reports every package as two kilograms heavier than its actual weight. What type of error is present? A. Random error B. Systematic error C. Omission error D. Sampling error Correct Answer: B. Systematic error Rationale: Systematic error produces a consistent and repeatable deviation from the true value. Because the scale is always two kilograms high, averaging additional measurements will not eliminate the problem. Random error varies unpredictably. Omission error involves missing values, while sampling error reflects differences between a sample estimate and its population value. Question 4 A hospital administrator identifies rising patient wait times, analyzes scheduling and staffing data, and then presents recommended changes to senior leadership. Which decision-making framework best organizes these activities? A. Deming’s PDCA cycle B. Porter’s value-chain model C. Davenport-Kim three-stage model D. Balanced scorecard model Correct Answer: C. Davenport-Kim three-stage model Rationale: The Davenport-Kim model organizes decision-making into framing the problem, solving the problem, and communicating results. Identifying wait times frames the issue, analyzing operational data supports problem-solving, and presenting recommendations communicates the findings. PDCA focuses on continuous improvement, the value chain examines value-creating activities, and the balanced scorecard measures organizational strategy and performance. Question 5 Repeated measurements of the same object vary unpredictably above and below the true value. Which type of error is most consistent with this pattern? A. Systematic error B. Random error C. Omission error D. Selection bias Correct Answer: B. Random error Rationale: Random error causes unpredictable fluctuations that may fall above or below the true value. Across many observations, these errors may partially offset one another, although they still reduce precision. Systematic error consistently shifts measurements in one direction. Omission error results from missing information, while selection bias originates from how participants or observations are included. Question 6 Why is statistical literacy especially important for organizational decision-makers? A. It guarantees that every decision will be correct B. It replaces professional judgment with formulas C. It supports evidence-based evaluation of uncertainty D. It prevents all forms of bias from entering research Correct Answer: C. It supports evidence-based evaluation of uncertainty Rationale: Statistics helps decision-makers summarize information, estimate uncertainty, compare alternatives, and draw defensible conclusions from data. It cannot guarantee perfect decisions because evidence may be incomplete or uncertain. Statistics should complement rather than replace professional judgment. Appropriate methods reduce bias, but no statistical technique can completely prevent bias caused by poor design, measurement, or interpretation. Question 7 A regional manager notices that customer complaints have increased but has not yet determined their cause. Under the Davenport-Kim model, which activity should occur first? A. Collect every available customer record B. Define the decision problem and its boundaries C. Present preliminary recommendations D. Select a statistical significance level Correct Answer: B. Define the decision problem and its boundaries Rationale: Problem recognition belongs to the framing stage. The manager must clarify what is happening, why it matters, who is affected, and what decision must be made before collecting or analyzing data. Gathering all records without a clear purpose may waste resources. Recommendations and significance testing occur only after the problem and analytical approach have been properly defined. Question 8 Several survey participants leave the household-income item blank. If the missing responses are ignored without investigation, what type of problem may result? A. Omission error and distorted estimates B. Perfect reliability C. Increased measurement validity D. Elimination of response bias Correct Answer: A. Omission error and distorted estimates Rationale: Blank fields create omission errors. If missingness is related to income level, privacy concerns, or other participant characteristics, ignoring the missing data may distort the results. Missing information does not increase reliability or validity and may worsen rather than eliminate response bias. Analysts should examine the pattern of missingness and use an appropriate treatment strategy. Question 9 A researcher surveys only employees who attend an optional wellness seminar and then generalizes the findings to the entire workforce. Which problem is most evident? A. Selection bias B. Instrument calibration error C. Autocorrelation D. Heteroscedasticity Correct Answer: A. Selection bias Rationale: Selection bias occurs when the sampling process produces a group that differs systematically from the target population. Wellness-seminar attendees may be more health-conscious than other employees. Calibration error involves inaccurate measuring instruments. Autocorrelation concerns relationships between observations over time, while heteroscedasticity describes unequal error variance in regression. Question 10 A research team has clearly defined its question and is now gathering survey responses, operational records, and demographic information. Which stage of the Davenport-Kim model is primarily represented? A. Framing the problem B. Solving the problem C. Communicating results D. Monitoring implementation Correct Answer: B. Solving the problem Rationale: Data collection and analysis are central activities in the problem-solving stage. Researchers gather relevant evidence, evaluate patterns, test assumptions, and compare possible solutions. Framing occurs earlier when the question is defined, while communicating results occurs later when conclusions are presented. Monitoring implementation may follow the decision but is not one of the model’s three principal stages.