Unit 1: Exploring One-Variable Data and Collecting Data
Statistics · Unit 1 · Paper 2

Exploring One-Variable Data and 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 95 terms and is the same for everyone, so a teacher can assign “Unit 1, Paper 2” 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 32 min 29 points0/17 attempted
1

Density curve

2

Stratified random sample

3

Effect of an outlier on mean and median

4

Replication

5

Factor, level, treatment

6

Retrospective versus prospective

7

Standardizing does not normalize

8

Side-by-side boxplots

9

Why context is scored

10

Naming the direction of skew

11

Normal probability plot

12

Systematic sample

Short answer 1. Define or explain: Cumulative relative frequency plot

3 pts

Short answer 2. Define or explain: Histogram vs bar chart

3 pts

Short answer 3. Define or explain: Double-blind

3 pts

Short answer 4. Define or explain: Undercoverage

3 pts

Free response

5 pts

A high school with 1,800 students is considering moving to a later start time. The principal wants to estimate the proportion of students who favor the change. A student journalist posts a poll on the school's social media page and reports that, of the 240 students who responded, 78 percent favor the later start.

A. Identify the type of sample the journalist obtained and explain why the reported 78 percent is likely to be a biased estimate. Indicate the likely direction of the bias.

B. The school has 500 first-year students, 460 sophomores, 440 juniors, and 400 seniors. Describe how to select a stratified random sample of 180 students, stratified by grade level, and explain one advantage of stratifying here.

C. Explain why the results of a well-designed survey of these students could not, by themselves, establish that a later start time causes improved academic performance.