A variable whose values are determined by chance.
Random Variable
This graph is commonly used to display the shape of a quantitative distribution.
Histogram
A sampling method where every group has the same chance of being chosen.
Cluster Sample
The probability of an event not occurring is found using this rule.
Complement Rule
Bias caused by wording that influences responses.
Response Bias
The long-run proportion of times an outcome occurs.
Probability
A graph that shows cumulative relative frequency.
Ogive
A sample chosen entirely by chance.
Simple Random Sample
If P(A \u2229 B) = P(A)P(B), the events are this.
Independent
A study that observes individuals without imposing treatments.
Observational Study
Two events with no outcomes in common are called this.
Mutually Exclusive
A display useful for identifying outliers and skewness.
Boxplot
In an experiment, this group receives no treatment or a placebo.
Control Group
The probability that event A occurs given event B has occurred.
Conditional Probability
The number of successes in a fixed number of trials in a binomial setting.
Binomial Random Variable
A probability distribution where there are only two outcomes per trial.
Binomial Distribution
This type of distribution is centered with equal tails on both sides.
Symmetric Distribution
Researchers use this to reduce the placebo effect.
Blinding
The rule used to combine probabilities of two events occurring.
Addition Rule
A rule assigning probabilities to outcomes of a random variable.
Probability Distribution
The average outcome of a random variable over many trials.
Expected Value
A graph showing probabilities for each value of a discrete random variable.
Probability Distribution Graph
An experiment design strategy that groups similar subjects together first.
Blocking
A simulation should use this to imitate chance behavior accurately.
Randomization
The standard deviation of a random variable measures this.
Variability