Straighterline Introduction to Statistics Exam Questions With
100% Verified Correct Answers |2026 Updated Guaranteed
Pass.
Association (does/does not) imply causation. - Answer -Does not
Lurking Variable - Answer -a variable that is not among the explanatory or response variables in
a study, but could substantially affect your interpretation of the relationship among those
variables
Simpson's paradox - Answer -When a lurking variable causes you to rethink the direction of an
association
Probability sampling plan - Answer -any sampling plan that relies on random selection (avoids
bias).
Simple Random Sampling - Answer -Every member of the population has an equal probability of
being selected for the sample
Cluster Sampling - Answer -Used when the population is naturally divided into groups. Take a
random sample of clusters and use all individuals within those clusters as the sample.
1|Page
, Stratified sampling - Answer -Used when the population is naturally divided into sub-
populations called stratum. Choose a simple random sample from each stratum and use these
together as the sample.
Multistage sampling - Answer -a probability sampling technique involving at least two stages: a
random sample of clusters followed by a random sample of people within the selected clusters
Observational study - Answer -values of the variable or variables of interest are recorded as they
naturally occur; no interference
Sample surveys - Answer -a particular type of observational study in which individuals report
variables' values themselves, frequently by giving their opinions.
Experiment - Answer -researchers "take control" of the values of the explanatory variable
because they want to see how changes in the value of the explanatory variable affect the
response variable
The Complement Rule - Answer -P(not A) = 1 - P(A)
useful for finding events of the type "at least one of..."
General Addition Rule - Answer -P(A or B) = P(A) + P(B) - P(A and B)
2|Page
100% Verified Correct Answers |2026 Updated Guaranteed
Pass.
Association (does/does not) imply causation. - Answer -Does not
Lurking Variable - Answer -a variable that is not among the explanatory or response variables in
a study, but could substantially affect your interpretation of the relationship among those
variables
Simpson's paradox - Answer -When a lurking variable causes you to rethink the direction of an
association
Probability sampling plan - Answer -any sampling plan that relies on random selection (avoids
bias).
Simple Random Sampling - Answer -Every member of the population has an equal probability of
being selected for the sample
Cluster Sampling - Answer -Used when the population is naturally divided into groups. Take a
random sample of clusters and use all individuals within those clusters as the sample.
1|Page
, Stratified sampling - Answer -Used when the population is naturally divided into sub-
populations called stratum. Choose a simple random sample from each stratum and use these
together as the sample.
Multistage sampling - Answer -a probability sampling technique involving at least two stages: a
random sample of clusters followed by a random sample of people within the selected clusters
Observational study - Answer -values of the variable or variables of interest are recorded as they
naturally occur; no interference
Sample surveys - Answer -a particular type of observational study in which individuals report
variables' values themselves, frequently by giving their opinions.
Experiment - Answer -researchers "take control" of the values of the explanatory variable
because they want to see how changes in the value of the explanatory variable affect the
response variable
The Complement Rule - Answer -P(not A) = 1 - P(A)
useful for finding events of the type "at least one of..."
General Addition Rule - Answer -P(A or B) = P(A) + P(B) - P(A and B)
2|Page
