WGU D582 INTRO TO STATISTICS FOR
RESEARCH OA CERTIFICATION SCRIPT
2026 QUESTIONS WITH SOLUTIONS
GRADED A+
◍ stratified sample.
Answer: Divides population in to subgroups based on characteristic, then
randomly pulls from each
◍ significant difference (a).
Answer: usually .05 is the acceptable default. anything above or below that
is significant (Ex. .49 & .60, but .59 is okay.)
◍ random sample.
Answer: every member has equal chance of being selected
◍ r² (coefficient of determination).
Answer: • 0.00-0.29 → Weak pos/neg• 0.30-0.69 → Moderate pos/neg•
0.70-1.00 → Strong pos/neg
◍ Interval.
Answer: Difference between values is meaningful and consistent,
quantitative, there is no zero point
◍ Information bias.
Answer: response and conscious bias
◍ conscious bias.
Answer: surveyor is actively seeking a certain response
◍ tukey's post-hoc test.
Answer: to see which group means differ (ANOVA Tests)
, ◍ t-test.
Answer: compares results of two tests
◍ Qualitative research.
Answer: exploratory; data not characterized by numbers (textural, visual, or
oral)
◍ if t-stat is within critical value range.
Answer: not significant/fail to reject (aka passes the range)
◍ T-test.
Answer: Compares results of two tests
◍ continuous.
Answer: Infinite possible values, can be measured
◍ Nomical.
Answer: lowest level of measurement; labels/categories that only contain 2
combonations (ex. pass/fail; cereal brand, etc.)
◍ pearson's r (correlation coefficient).
Answer: The closer it is to 1, the stronger the positive relationship (ranges
from -1 to 1)
◍ mean.
Answer: average, add all values and divide by number of values
◍ alternative hypothesis.
Answer: contradicts the null. if we reject a hypothesis we consider this.
◍ critical value > statistic.
Answer: Fail to reject
◍ assumptions for chi-square tests.
Answer: - categorical- 80% of categories must have an expected value of 5+
◍ residuals.
Answer: actual y - predicted y.(key words- difference, accuracy, fit)
RESEARCH OA CERTIFICATION SCRIPT
2026 QUESTIONS WITH SOLUTIONS
GRADED A+
◍ stratified sample.
Answer: Divides population in to subgroups based on characteristic, then
randomly pulls from each
◍ significant difference (a).
Answer: usually .05 is the acceptable default. anything above or below that
is significant (Ex. .49 & .60, but .59 is okay.)
◍ random sample.
Answer: every member has equal chance of being selected
◍ r² (coefficient of determination).
Answer: • 0.00-0.29 → Weak pos/neg• 0.30-0.69 → Moderate pos/neg•
0.70-1.00 → Strong pos/neg
◍ Interval.
Answer: Difference between values is meaningful and consistent,
quantitative, there is no zero point
◍ Information bias.
Answer: response and conscious bias
◍ conscious bias.
Answer: surveyor is actively seeking a certain response
◍ tukey's post-hoc test.
Answer: to see which group means differ (ANOVA Tests)
, ◍ t-test.
Answer: compares results of two tests
◍ Qualitative research.
Answer: exploratory; data not characterized by numbers (textural, visual, or
oral)
◍ if t-stat is within critical value range.
Answer: not significant/fail to reject (aka passes the range)
◍ T-test.
Answer: Compares results of two tests
◍ continuous.
Answer: Infinite possible values, can be measured
◍ Nomical.
Answer: lowest level of measurement; labels/categories that only contain 2
combonations (ex. pass/fail; cereal brand, etc.)
◍ pearson's r (correlation coefficient).
Answer: The closer it is to 1, the stronger the positive relationship (ranges
from -1 to 1)
◍ mean.
Answer: average, add all values and divide by number of values
◍ alternative hypothesis.
Answer: contradicts the null. if we reject a hypothesis we consider this.
◍ critical value > statistic.
Answer: Fail to reject
◍ assumptions for chi-square tests.
Answer: - categorical- 80% of categories must have an expected value of 5+
◍ residuals.
Answer: actual y - predicted y.(key words- difference, accuracy, fit)
