Performance Benchmark N.12.A.3

Students know repeated experimentation allows for statistical analysis and unbiased conclusions. E/S

Sample Test Questions

1st Item Specification: Explain that repeated trials and increased sample size increase the validity of experimental results.

Depth of Knowledge Level 1

  1. A student measures the length of a pendulum three times. The measurements were 1.42 meters, 1.43 meters, and 1.45 meters. The actual length of the pendulum was 1.89 meters. What can be said about these measurements? The measurements are
  1. accurate.
  2. precise.
  3. aligned.
  4. exact.
  1. Which term represents the degree to which data matches the true or accepted value?
  1. Accuracy
  2. Precision
  3. Correlation coefficient
  4. Alignment standard

Depth of Knowledge Level 2

  1. Use the data tables and provided information to answer the following question.Working in groups, students were instructed to develop and conduct an investigationto determine the density of silver. Each lab group was provided with an identical sample of silver. The data tables for two groups are shown below.

Group 1
Trail 1 / Trial 2 / Trail 3 / Average
Mass (g) / 89.3 / 91.5 / 90.2 / 90.3
Volume (cm3) / 12.3 / 11.9 / 12.1 / 12.1
Density (g/cm3) / 7.3 / 7.7 / 7.5 / 7.5
Group 2
Trail 1
Mass (g) / 91.5
Volume (cm3) / 12.8
Density (g/cm3) / 7.1

Which group’s data is most likely closest to the accepted value for the density of silver?

  1. Group 1, because they conducted the experiment three times with measurements that are close to each other.
  2. Group 2, because with careful measurements only one run of the experiment is needed to ensure accuracy.
  3. Group 1, because the averaged data helps to confirm errors throughout each trial.
  4. Group 2, because they were able to complete the measurements more efficiently.
  1. Use the data tables and provided information to answer the following question. For a final lab grade, a Physics class is asked to find the rate of acceleration due to gravitational force. The class divided into five groups and began to discuss their experimental design. All of the groups decided to perform different experiments and began to collect data. The data tables of the five different experiments are shown below.

Class Data
Group 1 / Group 2 / Group 3 / Group 4 / Group 5
Velocity (m/s) / 12.4 / 11.2 / 25.5 / 5.35 / 5.86
Time (s) / 1.22 / 1.21 / 2.56 / 0.703 / 0.480
Calculated Acceleration (m/s2) / 10.2 / 9.26 / 9.96 / 7.61 / 12.2

What should the class decide to do next to insure the lowest amount of error in their data?

  1. The class decides that the data is too varied so they should ignore it and run the experiments over again.
  2. Group 4 is asked to do the lab over because they have collected data that doesn’t match the other groups.
  3. The groups decide to compare their results with the other Physics classes’ results before committing to a final answer.
  4. The groups decides to vote on the best experiment and have that group run the lab again to use the new results as the correct answer.

2nd Item Specification: Explain the importance of independent replication of experimental results.

Depth of Knowledge Level 1

  1. What makes a scientific explanation different from a non-scientific explanation? Scientific explanations are
  1. based on assumptions.
  2. predictable.
  3. not able to be changed.
  4. testable.
  1. Scientists publish the details of important experiments.Which of the following is NOT a reasonfor this?
  2. Their work can be repeated.
  3. Their experimental procedures can be reviewed.
  4. Others can try to reproduce the results.
  5. Others can turn their experiments into technology.

Depth of Knowledge Level 2

  1. A student just received their license to drive and is in the market for a used car. After saving her money she decides to go to the dealership to look for a suitable car. The salesman points out a car that she likes, but the car doesn’t sound normal after starting. What would be the best approach the student could use to evaluate the car?
  2. The student should trust the salesman because the car has been tested at the dealership.
  3. The student should take the car to an independent mechanic because the mechanic does not have an interest in the purchase of the car.
  4. The student should ask the salesman to take the car to their mechanic to evaluate the odd sound.
  5. The student should not worry about the noise because all cars sound different.
  1. Use the data tables and provided information to answer the following question. Working in groups, students were instructed to develop and conduct an investigation to determine the density of silver. Each lab group was provided with an identical sample of silver. The data tables for two groups are shown below.

Group 1
Trail 1 / Trial 2 / Trail 3 / Average
Mass (g) / 79.5 / 81.5 / 80.2 / 80.4
Volume (cm3) / 12.4 / 11.8 / 12.1 / 12.1
Density (g/cm3) / 6.4 / 6.9 / 6.6 / 6.6
Group 2
Trail 1 / Trial 2 / Trail 3 / Average
Mass (g) / 89.3 / 91.5 / 90.2 / 90.3
Volume (cm3) / 12.3 / 11.9 / 12.1 / 12.1
Density (g/cm3) / 7.3 / 7.7 / 7.5 / 7.5

The accepted value for the density of silver is 7.3 g/cm3

Which of the following statements below BEST explains the importance of independent replication of experimental results.

  1. Group 1 has data that is independent of Group 2, and that is why their data is more accurate.
  2. If Group 2 was not independent of Group 1, then Group 1 would not have found that they had calculated the incorrect density for silver.
  3. Because Group 1 and Group 2 were independent they could compare their results for discrepancies.
  4. Because the groups were independent they were sure that their calculated densities were correct.
  1. A new drug, said to cure Attention Deficit Disorder, was presented to the United States Food and Drug Administration (FDA) for approval. The makers of this drug conducted a study on 20 people, in the South American rainforest, and found that 18 out of 20 patients improved their concentration while taking this medication. Based on this information, should the FDA approve this new drug?
  2. Yes, because the drug proved to be effective for most of the people that took it.
  3. No, because the drug is meant for people in cities so it needs to be tested by the drug company, on people in cities.
  4. Yes, because the drug will help people with Attention Deficit Disorder.
  5. No, because the drug company that makes the drug should hire an independent company to test the drugs effectiveness.

3rd Item Specification:Given two or more sets of data among which there is some disagreement, discuss conclusions that can or cannot be supported based on the combined data.

Depth of Knowledge Level 1

  1. In August 2006, the International Astronomical Union removed Pluto’s status as a planet and named it a dwarf planet. What prompted the reclassification of Pluto?
  1. A new telescope introduced in 2006 allowed scientists to see a better view of Pluto.
  2. Scientists based their decision on known data from Pluto and other objects in the solar system.
  3. A manned mission to Pluto provided evidence to make it a dwarf planet.
  4. Scientists were biased to make the solar system have ten planets.
  1. Scientists have observed data that shows the average temperature of the Earth has risen over the past century. However, there is a debate among some scientists if the temperature rise is caused by human activity or natural climate change. What is the source of the global warming debate?
  2. Errors in the data collection process.
  3. Political bias among scientists and their position.
  4. Different interpretations of the same data.
  5. Failure of some scientists to publish their data.

Depth of Knowledge Level 2

  1. During the early 20th century stomach ulcers were common in people with high stress jobs, such as Physicians. Due to the high stress of these professions and the high rate of stomach ulcers of people in the profession, it was thought that stomach ulcers were caused by high stress. In 1982 data showed that ulcers were caused by a bacterium. The data was not widely supported as it refutes the common idea that ulcers are caused by stress. Which of the following statements are NOT supported by both lines of data?
  2. When the human body is under high stress the immune systems function slows.
  3. Pilots are at a high risk for ulcers because of their stress level and contact with many different diseases due to travel.
  4. Watchmakers are at a low risk for ulcers because they typically work in a low stress environment and have little contact with others.
  5. All people have stress, but not all people have ulcers.
  1. Pellagra is a disease that first appeared in the United States in the 1820s and was known as the disease of the four Ds: dermatitis, diarrhea, dementia, and death. There was a debate among scientists if pellagra was caused by poor diet or an infectious agent. Which of the following supports the fact that pellagra is caused by a poor diet?
  2. Pellagra was common in the North, especially in universities and business offices.
  3. Orphans provided with fresh vegetables, meat, and milk recovered from Pellagra or never got it.
  4. Staff at institutions such as hospitals, prisons, and orphanages did not develop Pellagra.
  5. Pellagra was not common in sailors, especially sailors that crossed the Atlantic Ocean.

Performance Benchmark N.12.A.3

Students know repeated experimentation allows for statistical analysis and unbiased conclusions. E/S

Answers to Sample Test Questions

  1. B, DOK Level 1
  2. A, DOK Level 1
  3. A, DOK Level 2
  4. C, DOK Level 2
  5. D, DOK Level 1
  6. D, DOK Level 1
  7. B, DOK Level 2
  8. C, DOK Level 2
  9. D, DOK Level 2
  10. B, DOK Level 1
  11. C, DOK Level 1
  12. D, DOK Level 2
  13. B, DOK Level 2