Unit 3: Collecting Data
Statistics · Unit 3 · Paper 3

Collecting Data unit test

A test on this unit alone, marked as a percentage and a letter grade — for the test your class is actually sitting, rather than for May. Answer everything, then submit once: seeing the answer to question 3 before attempting question 4 makes the final percentage meaningless.

Paper 1Paper 2Paper 3
Each paper is built from this unit’s 24 terms and is the same for everyone, so a teacher can assign “Unit 3, Paper 3” and every student sits the identical test. Multiple choice is marked objectively; the written sections you mark yourself against the model answer and rubric.
Suggested time 35 min 32 points0/17 attempted
1

Population vs sample

2

Convenience and voluntary response samples

3

Simple random sample

4

Matched pairs design

5

Scope of inference

6

Parameter vs statistic

7

Placebo and control group

8

Blocking

9

Blinding and placebo effect

10

Undercoverage

11

Three principles of experimental design

12

Cluster sample

Short answer 1. Define or explain: Random assignment vs random selection

3 pts

Short answer 2. Define or explain: Nonresponse bias

3 pts

Short answer 3. Define or explain: Completely randomized vs block design

3 pts

Short answer 4. Define or explain: Why a large biased sample is worse than a small random one

3 pts

Free response

8 pts

A researcher has 60 tomato seedlings and wants to compare the effect of two fertilizers (A and B) on total tomato yield. Half of the garden receives full sun and the other half is partly shaded.

Describe a completely randomized design for this experiment.

Explain the purpose of random assignment in this experiment.

A colleague suggests blocking by sunlight instead. Describe how the randomized block design would work and explain why it might be preferable here.

Suppose the block design shows a significantly higher mean yield for Fertilizer A. Discuss what can and cannot be concluded, including whether the result generalizes beyond this study.