2018, Question 2 · 4 points
Recycling survey bias and randomized response
Work back from a confidence interval to the sample size, explain how face to face questioning could bias the estimate, and use a coin flip response scheme to find an expected count and a new estimate.
This exam had six free-response questions, each scored from 0 to 4. Its Question 6, the Investigative Task, is no longer part of the exam. The current exam has 4 free-response questions in 90 minutes. The skills these questions practice still count.
1 Read the question
The question is College Board's, from the 2018 exam. It starts on page 7 of the PDF. College Board no longer posts this exam, so it opens from the copy of College Board's PDF that the Internet Archive saved on December 9, 2025.
2 Write your answer
Answer each part the way you would on the exam, in full sentences, with your work shown. Your writing saves as you type.
3 Score it
Score your answer against College Board's scoring guidelines, one point at a time. Give yourself a point only when your answer says what the guideline asks for.
Scoring guidelines (PDF, page 6) What the exam readers saw (Chief Reader report)
Question, scoring guidelines and Chief Reader report: College Board, from the Internet Archive. The title, summary are ours.