Back to Distinguish surveys, experiments, and observational studies — Problem 6 · Task Set 14

Exercises: Distinguish Surveys, Experiments, and Observational Studies

Work through each section in order. For classification problems, decide whether a study is a sample survey, an observational study, or a randomized experiment, and use two separate questions: "Was there random SELECTION?" (which governs whether results generalize to a population) and "Was there random ASSIGNMENT?" (which governs whether a difference can be read as causation). For explanation problems, write in complete sentences.

Grade 10·21 problems·~35 min·Common Core Math - HS Statistics and Probability·group·hss-ic-b-3

Work through problems with immediate feedback

Fluency Practice

Classify each study and identify the role of randomization.

An observational study finds that students who eat breakfast have higher grades than students who skip it. Which conclusion is justified?

Eating breakfast is associated with higher grades, but the study cannot establish that breakfast causes higher grades because of possible confounding variables.

Eating breakfast causes higher grades, because the difference is clear.

Grades cause students to eat breakfast.

There is no relationship between breakfast and grades.