Designing a Scientific Experiment

Education · 10 questions

Ten multiple-choice questions on experimental controls, sampling, and variable identification.

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1. Which method is especially useful when important subgroups need representation in the sample?

   1. Systematic sampling
   2. Stratified sampling
   3. Convenience sampling
   4. Simple random sampling
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   B) Stratified sampling

2. Which type of definition specifies how a variable will be measured or implemented in an experiment?

   1. Operational definition
   2. Theoretical framework
   3. Conceptual definition
   4. Research hypothesis
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   A) Operational definition

3. What design feature applies when neither participants nor researchers assessing outcomes know group assignments?

   1. Cluster randomization
   2. Single-blinding
   3. Open-label design
   4. Double-blinding
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   D) Double-blinding

4. How does a control condition help evaluate an intervention's effect?

   1. Prevention of participant loss
   2. Randomization of sample selection
   3. Elimination of measurement error
   4. A reference for comparing the intervention's effect
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   D) A reference for comparing the intervention's effect

5. What design approach groups units by baseline characteristics and assigns treatments within each group?

   1. Stratified sampling
   2. Blocking
   3. Unmatched randomization
   4. Cluster sampling
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   B) Blocking

6. Which method gives every possible sample of a specified size an equal chance of selection?

   1. Systematic sampling
   2. Simple random sampling
   3. Convenience sampling
   4. Stratified sampling
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   B) Simple random sampling

7. What do separate applications of a treatment to different experimental units under the same conditions provide?

   1. Observer blinding
   2. Sample stratification
   3. Independent replicates
   4. Repeated measurements on one unit
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   C) Independent replicates

8. In an observational study, what kind of variable may be a confounder when related to both the exposure and the outcome?

   1. A third variable related to exposure and outcome
   2. A mediator arising after exposure
   3. A variable affecting only the measuring instrument
   4. A variable related only to the outcome
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   A) A third variable related to exposure and outcome

9. With the same sampling design and similar conditions, which change generally reduces sampling error?

   1. Increasing measurement frequency
   2. Shortening the data collection period
   3. Increasing the sample size
   4. Blinding researchers
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   C) Increasing the sample size

10. In an experiment, participants are randomly assigned to two treatment groups. What does this assignment primarily support?

    1. An increase in sample size
    2. Consistency of the measuring instrument
    3. Balancing confounding factors across groups
    4. Equal representation of every subgroup
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    C) Balancing confounding factors across groups