Studies and Experiments
What is it called when you are looking at data that already exists and no treatment is imposed?
Observational Study
Name the three sample types
Random, Convenience, Voluntary (Response)
Name the four principles of a good experiment
Compare, Randomize, Control, Replicate
what is the percent threshold for statistical significance?
5%
What does the sun help the skin produce?
Vitamin D
What is it called when you split participants into two or more groups and impose a treatment to see the effects?
Experiment
Name the three types of bias
Response Bias, Undercoverage, Nonresponse
Define the principle "Compare"
Having two or more groups,
True or False: The percentage calculated from a set of randomized simulated trials has to be less than 5% to be considered statistically significant.
True
What is a group of flamingos called?
A flamboyance
The University of Memphis recruited 36 cyclists to participate in a study. Using a random process, half of the cyclists were assigned to drink Red Bull with caffeine while the other half of cyclists drank a near identical Red Bull without caffeine.
The group of cyclists that drank Red Bull with caffeine showed a 7% increase in their cycling endurance over the other group.
Is this an observational study or an experiment?
Experiment: treatment was imposed!
Which of the following sample types should you use to minimize bias?
a. Convenience Sample
b. Random Sample
c. Voluntary Response Sample
B. Random Sample
Define the principle "Replicate"
Having enough participants in your experiment.
Out of a set of 200 simulated randomized trials, it was found that 22 of the trial resulted in a gap that was as large as the gap observed in the experiement.
Calculate the percentage of those trials.
11%
Which famous artist painted The Mona Lisa?
Leonardo Da Vinci
Name the four steps of the Statistical Investigative Process
Create a Question
Collect Data
Analyze Data
Interpret Results (draw a conclusion)
Which type of assignment allows us to conclude a cause-and-effect relationship in an experiment?
Random Assignment
Define the principle "Randomize"
Making sure you are randomly assigning groups.
True or False: If the results from an experiment are statistically significant, then that means that the results from the treatment imposed happened by chance.
False: Statistically significant means the treatment caused the observed changes.
How many eyes does a bee have?
5 eyes
A recent PEW Research Center study interviewed 743 U.S. teenagers and found that those teens that keep their phone away from their bed are much more likely to get enough sleep than those teens who keep their phone close to the bed.
True or False: This study allows us to conclude that keeping their phone away from their bed causes them to get more sleep. Explain
False: We need an experiment to show a cause-and-effect relationship. Also, there are confounding variables (parents may be more strict)
Why is it important to use random sampling when designing and executing an experiment?
Because random sampling is the only way we can make a general conclusion about the population that we sampled from.
Define the principle "Control"
Making sure you are keeping all other variables constant except for the variable you want to observe.
Out of a set of 200 simulated randomized trials, it was found that 22 of the trial resulted in a gap that was as large as the gap observed in the experiment.
Based on the data above, did the treatment imposed cause the changes, or could it have happened by chance? Why?
It could've happened by chance. The percentage is 11%, meaning it's above the SS threshold (so it's not SS).
What does BMW stand for?
Bavarian Motor Works (or Bayerische Motoren Werke)