Definitions
What is the placebo effect?
A phenomenon where a dummy treatment seems to improve measurements based only on the participant's assumption that they are recieving a real treatement.
To satisfy the randomness condition, a study must either use a random sample or...
Random assignment of treatment
In a study on drug effectiveness, both the administrators and the participants don't know which particiapnts are taking the placebo vs the real drug. What type of study is this?
A double-blind study
Median
What type of distribution looks like a bell when graphed?
Normal distribution
What are experimental units?
A physical entity that is the primary unit of interest in an experimental trial.
Sample must be less than what percentage of the population?
10%
A study posts an ad in the hallway and any volunteers who are interested can scan the ad and complete the survey. What type of sample is this?
Convenience
Name the measure of spread that is calculated using the data minimum and maximum.
Range
What type of distribution uses data points from every possible sample in a population?
A sampling distribution
What is a confounding variable?
An uncontrolled variable that influences the dependent variable, making it look like the change is caused by the independent variable.
To significance tests for mean, the population sample needs to be normally distributed or...
Greater than or equal to 30
Define undercoverage
Some members of the population are inadeqately represented in the sample.
Name the measure of spread that is used in the 1.5 outlier rule.
IQR
In what type of distribution do the statisticians count trials until success?
Geometric
What is regression model?
A model that explores the relationship between two variables as measurements on the X and Y axis.
To satisfy the large counts condition for proportions, the np and n(p-1) must be greater than...
10
What does random sample allow for?
Inference
We reject the null hypothesis is the p-calue is ___than the significance level.
About ___% of data is within one standard deviation of the mean in a normal distribution.
64
What are mutually exclusive outcomes?
Events that cannot happen at the same time when looking at probability.
For a binomial distribution, what does the I in BINS stand for?
Independence
What does random assignment allow for?
Cause and effect relationship can be determined
If a researcher rejects the null when the null should not actually be rejected, what type of error is comitted?
Type 1
What shape does a geometric distribution have?
Right-skewed