AP Stats Chapter 13 MC Flashcards
We wish to compare the average ages of the math and science teachers at your high school. Which is the best way to collect the data? A) census B) sample survey C) observational study D) experiment E) simulation
A
A researcher identified 100 men over forty who were not exercising and another 100 men over forty with similar medical histories who were exercising regularly. She followed all the men for several years
to see if there was any difference between the two groups in the rate of heart attacks. This is a(n) …
A) survey B) prospective study C) retrospective study
D) randomized experiment E) matched pairs experiment.
B
Of A-D, which is not a critical part of designing a good experiment?
A) Control of known sources of variability. B) Random selection of subjects.
C) Random assignment of subjects to treatments.
D) Replication of the on a sufficient number of subjects. E) All of these are important.
B
In an experiment the primary purpose of blinding is to reduce …
A) bias. B) confounding. C) randomness. D) undercoverage. E) variation.
A
Does donating blood lower cholesterol levels? 50 volunteers have a cholesterol test, then donate blood, and then have another cholesterol test. Which aspect of experimental design is present?
A) randomization B) a control group C) a placebo D) blinding E) none of these
E
A researcher wants to compare the performance of three types of pain relievers in volunteers
suffering from arthritis. Because people of different ages may react differently to medication, the
subjects are split into two groups: under 60 and over 60. Subjects in each group are randomly assigned
to take one of the medications. Twenty minutes later they rate their levels of pain. This experiment …
A) is completely randomized. B) uses matched pairs. C) has two factors, medication and age.
D) has one factor (medication) blocked by age. E) has one factor (age) blocked by medication type.
D
If we wish to compare the average PSAT scores of boys and girls taking AP Statistics at this high
school, which would be the best way to gather these data?
A) census B) SRS C) stratified sample
D) observational study E) experiment
A
Does regular exercise decrease the risk of cancer? A researcher finds 200 women over 50 who
exercise regularly, pairs each with a woman who has a similar medical history but does not exercise,
then follows the subjects for 10 years to see which group develops more cancer. This is a
A) survey B) retrospective study C) prospective study
D) randomized experiment E) matched experiment
C
Which is important in designing a good experiment?
I. Randomization in assigning subjects to treatments.
II. Control of potentially confounding variables.
III. Replication of the experiment on a sufficient number of subjects.
A) I only B) I and II C) I and III D) II and III E) all three
E
Can watching a movie temporarily raise your pulse rate? Researchers have 50 volunteers check their pulse rates. Then they watch an action film, after which they take check their pulse rates once
more. Which aspect of experimentation is present in this research?
A) a placebo B) blinding C) randomization
D) a control group E) none of these
E
In an experiment the primary purpose of blocking is to reduce
A) bias. B) confounding. C) randomness. D) undercoverage. E) variation.
E
To check the effect of cold temperatures on the battery’s ability to start a car researchers purchased a battery from Sears and one from NAPA. They disabled a car so it would not start, put the car in a warm garage, and installed the Sears battery. They tried to start the car repeatedly, keeping track of the
total time that elapsed before the battery could no longer turn the engine over. Then they moved the car outdoors where the temperature was below zero. After the car had chilled there for several hours the researchers installed the NAPA battery and repeated the test. Is this a good experimental design?
A) Yes
B) No, because the car and the batteries were not chosen at random.
C) No, because they should have tested other brands of batteries, too.
D) No, because they should have tested more temperatures.
E) No, because temperature is confounded by brand.
E
Twenty dogs and 20 cats were subjects in an experiment to test the effectiveness of a new flea control chemical. Ten of the dogs were randomly assigned to an experimental group that wore a collar
containing the chemical, while the others wore a similar collar without the chemical. The same was done with the cats. After 30 days veterinarians were asked to inspect the animals for fleas and evidence of flea bites. This experiment is…
A) completely randomized with one factor: the type of collar
B) completely randomized with one factor: the species of animal
C) randomized block, blocked by species
D) randomized block, blocked by type of collar
E) completely randomized with two factors
C
