WGU D582 INTRO TO STATISTICS FOR
RESEARCH OA PRACTICE EXAMINATION
2026 QUESTIONS WITH ANSWERS
GRADED A+
◍ CI example: 99% CI for difference is -0.8 to -0.4 (does NOT contain 0).
Conclusion?.
Answer: Reject H₀ — significant difference at α = 0.01
◍ What distinguishes ratio numerical variables?.
Answer: They are categorized, ranked, evenly spaced, and have a natural
zero point, such as height or weight.
◍ Which sampling method: 20 homes from each of 10 townships (200 total)?.
Answer: Stratified sampling
◍ ONE-WAY ANOVA: when do you REJECT H₀ using p-value?.
Answer: When p-value < α
◍ DISCRETE or CONTINUOUS? → Distance traveled.
Answer: Continuous
◍ What makes a histogram approximately NORMAL?.
Answer: Bell-shaped — symmetric, single peak in the middle, tapering on
both sides
◍ What is a target population?.
Answer: A bounded set of individuals exhibiting variability whose pattern
we wish to understand.
◍ What are continuous numerical variables?.
Answer: Numerical variables that can take any value within a range,
, including infinite decimals and fractions.
◍ QUALITATIVE or QUANTITATIVE? → Years of experience.
Answer: Quantitative (numerical)
◍ What are variables?.
Answer: Traits or characteristics that can vary from one individual to
another.
◍ What are ecological studies?.
Answer: Studies that focus on the dynamic interconnected relationship
between human societies and their natural environments.
◍ Which sampling method: drawing 50 names from a hat at a conference?.
Answer: Simple random sampling
◍ Which sampling method: sampling all students in 10 randomly chosen
courses?.
Answer: Cluster sampling
◍ DISCRETE or CONTINUOUS? → Weight of a soil sample.
Answer: Continuous
◍ ANOVA: F-stat = 0.216, critical F = 0.432. Conclusion?.
Answer: Fail to reject H₀ — no significant difference (0.216 < 0.432)
◍ QUALITATIVE or QUANTITATIVE? → Department.
Answer: Qualitative (categorical)
◍ How is population proportion calculated?.
Answer: Using the formula = K/N, where K is the population count and N
is the total population.
◍ What is a statistic?.
Answer: A number summarizing something about the pattern of variability
in a sample.
◍ What is scientific communication?.
Answer: Scientific communication is a crucial component of high-quality
, research, ensuring accountability to various stakeholders.
◍ t-test: test stat = 4.02, critical value = 2.249. Conclusion?.
Answer: Reject H₀ — test stat exceeds critical value (4.02 > 2.249)
◍ What is a parameter in statistics?.
Answer: A number summarizing something about the pattern of variability
in a population.
◍ What are the ethical implications of open-access publishing?.
Answer: Open-access publishing raises concerns for researchers with
resource constraints and involves author-retained copyright issues.
◍ What is an INTERVAL variable?.
Answer: Numerical with equal spacing between values, but NO true zero
(e.g., temperature in Celsius or Fahrenheit, IQ scores)
◍ What are numerical/quantitative variables?.
Answer: Variables that represent measurable quantities expressed in
numbers.
◍ What are systematic errors?.
Answer: Errors that result from biased sampling, affecting all samples drawn
from the same population in a consistent manner.
◍ What is the relationship between gaps in knowledge and research
questions?.
Answer: Gaps in knowledge lead to the formulation of research questions
that guide the research process.
◍ What is the research cycle?.
Answer: The process that begins with gaps in background knowledge
leading to research questions.
◍ What is a sample frame?.
Answer: A sample frame is a comprehensive list or database of all elements
in a target population from which a research sample is drawn.
◍ What is SYSTEMATIC SAMPLING?.
RESEARCH OA PRACTICE EXAMINATION
2026 QUESTIONS WITH ANSWERS
GRADED A+
◍ CI example: 99% CI for difference is -0.8 to -0.4 (does NOT contain 0).
Conclusion?.
Answer: Reject H₀ — significant difference at α = 0.01
◍ What distinguishes ratio numerical variables?.
Answer: They are categorized, ranked, evenly spaced, and have a natural
zero point, such as height or weight.
◍ Which sampling method: 20 homes from each of 10 townships (200 total)?.
Answer: Stratified sampling
◍ ONE-WAY ANOVA: when do you REJECT H₀ using p-value?.
Answer: When p-value < α
◍ DISCRETE or CONTINUOUS? → Distance traveled.
Answer: Continuous
◍ What makes a histogram approximately NORMAL?.
Answer: Bell-shaped — symmetric, single peak in the middle, tapering on
both sides
◍ What is a target population?.
Answer: A bounded set of individuals exhibiting variability whose pattern
we wish to understand.
◍ What are continuous numerical variables?.
Answer: Numerical variables that can take any value within a range,
, including infinite decimals and fractions.
◍ QUALITATIVE or QUANTITATIVE? → Years of experience.
Answer: Quantitative (numerical)
◍ What are variables?.
Answer: Traits or characteristics that can vary from one individual to
another.
◍ What are ecological studies?.
Answer: Studies that focus on the dynamic interconnected relationship
between human societies and their natural environments.
◍ Which sampling method: drawing 50 names from a hat at a conference?.
Answer: Simple random sampling
◍ Which sampling method: sampling all students in 10 randomly chosen
courses?.
Answer: Cluster sampling
◍ DISCRETE or CONTINUOUS? → Weight of a soil sample.
Answer: Continuous
◍ ANOVA: F-stat = 0.216, critical F = 0.432. Conclusion?.
Answer: Fail to reject H₀ — no significant difference (0.216 < 0.432)
◍ QUALITATIVE or QUANTITATIVE? → Department.
Answer: Qualitative (categorical)
◍ How is population proportion calculated?.
Answer: Using the formula = K/N, where K is the population count and N
is the total population.
◍ What is a statistic?.
Answer: A number summarizing something about the pattern of variability
in a sample.
◍ What is scientific communication?.
Answer: Scientific communication is a crucial component of high-quality
, research, ensuring accountability to various stakeholders.
◍ t-test: test stat = 4.02, critical value = 2.249. Conclusion?.
Answer: Reject H₀ — test stat exceeds critical value (4.02 > 2.249)
◍ What is a parameter in statistics?.
Answer: A number summarizing something about the pattern of variability
in a population.
◍ What are the ethical implications of open-access publishing?.
Answer: Open-access publishing raises concerns for researchers with
resource constraints and involves author-retained copyright issues.
◍ What is an INTERVAL variable?.
Answer: Numerical with equal spacing between values, but NO true zero
(e.g., temperature in Celsius or Fahrenheit, IQ scores)
◍ What are numerical/quantitative variables?.
Answer: Variables that represent measurable quantities expressed in
numbers.
◍ What are systematic errors?.
Answer: Errors that result from biased sampling, affecting all samples drawn
from the same population in a consistent manner.
◍ What is the relationship between gaps in knowledge and research
questions?.
Answer: Gaps in knowledge lead to the formulation of research questions
that guide the research process.
◍ What is the research cycle?.
Answer: The process that begins with gaps in background knowledge
leading to research questions.
◍ What is a sample frame?.
Answer: A sample frame is a comprehensive list or database of all elements
in a target population from which a research sample is drawn.
◍ What is SYSTEMATIC SAMPLING?.
