Q2 L1 · Quiz
Weekly quiz · Measuring Plant Height: Protocol, Calibration, and Measurement Error
Assessment Appendix — AP Statistics · Week 10 Quiz
Quarter 2, Week 1 · Lessons 2.1–2.2 · Measuring Plant Height: Protocol, Calibration, and Measurement Error; Graphing Growth Trajectories with Error Bars
| # | Item | Answer / look-fors / scoring | Pts | Lesson · standards |
|---|---|---|---|---|
| 1 | Which term best matches this description? Unpredictable variation (leaf movement, eye angle) that averages out with more measurements. | (D) random error. | 1 | L2.1 · CED Topic 1.2, 1.7; LO 1.2.A, 1.2.B, 1.2.C; Skill 2.A, 3.B |
| 2 | Which term best matches this description? Consistent bias in one direction (ruler offset, always pressing into soil); it does not average out and can create a false treatment difference if applied to one cell. | (E) systematic error. | 1 | L2.1 · CED Topic 1.2, 1.7; LO 1.2.A, 1.2.B, 1.2.C; Skill 2.A, 3.B |
| 3 | Choose the word or phrase that best completes the sentence: Good data come from a consistent, written protocol. Random error is reduced by replication; ________ must be prevented by design. | (C) systematic error. | 1 | L2.1 · CED Topic 1.2, 1.7; LO 1.2.A, 1.2.B, 1.2.C; Skill 2.A, 3.B |
| 4 | Seedling heights have mean 7.5 cm and SD 1.6 cm. Each height is converted to millimeters and then 5 mm is added for the pot rim. What are the new mean and SD? | (C) Mean 80 mm; SD 16 mm. Multiplying scales both mean and SD; adding a constant shifts only the mean. | 1 | L2.1 · CED Topic 1.2, 1.7; LO 1.2.A, 1.2.B, 1.2.C; Skill 2.A, 3.B; item skill 3.A |
| 5 | The class numbers every plant in the garden and uses a random number generator to choose 30. Which sampling method is this? | (D) simple random sample. Match the selection process to the method definitions. | 1 | L2.1 · CED Topic 1.2, 1.7; LO 1.2.A, 1.2.B, 1.2.C; Skill 2.A, 3.B; item skill 1.C |
| 6 | Short Free Response: Answer each part using evidence from this week’s garden investigations. | 4 | L2.1, 2.2 · CED Topic 1.2, 1.7; LO 1.2.A, 1.2.B, 1.2.C; Skill 2.A, 3.B; CED Topic 1.8, 1.9; LO 1.8.A, 1.8.B, 1.9.A; Skill 3.A, 4.A | |
| (a) Explain the difference between accuracy and precision. | Accuracy = near true; precision = repeatable. | 1 | ||
| (b) Describe one systematic error you prevented today. | Systematic examples: ruler offset, measuring to a different leaf. | 1 | ||
| (c) Record the tallest plant in each cell. | Heights recorded with units. | 1 | ||
| (d) Describe the trend in your graph. | Trend described with values and units. | 1 |