One-Variable Data
Name one graph used for displaying quantitative data.
Dotplot, histogram, boxplot, or stem-and-leaf plot
What is the goal of random sampling?
To get a representative sample of the population
What does P(A) represent?
The probability that event A occurs
What is a random variable?
A numerical value that comes from a random process
What is a confidence interval used to estimate?
A population parameter
Which measure of center is least affected by outliers?
The median
What type of study can show cause-and-effect?
A randomized experiment
What does it mean if two events are independent?
One event does not affect the probability of the other
What does expected value represent?
The long-run average result
What does a small p-value suggest?
Strong evidence against the null hypothesis
What does the Interquartile Range (IQR) measure?
The spread of the middle 50% of the data
Why can’t observational studies show causation?
Because confounding variables are not controlled
When are two events mutually exclusive?
They cannot happen at the same time
What does the “B” in BINS stand for?
Binary outcomes (success or failure)
What does it mean to reject the null hypothesis?
The data provides enough evidence for the alternative claim
A distribution is skewed right. How do the mean and median compare?
The mean is greater than the median
Name one type of sampling bias
Voluntary response, nonresponse, or undercoverage
How can you tell if two events are independent using probabilities?
If P(A∣B)=P(A)
When should a geometric distribution be used?
When counting the number of trials until the first success
What is a Type I error?
Rejecting a true null hypothesis
A student scores at the 90th percentile on a test. What does this mean?
The student scored higher than 90% of students who took the test
What is the advantage of a matched pairs design?
It reduces variability by comparing similar subjects or the same person twice
Why are simulations helpful when finding probabilities?
They show long-run behavior when formulas are hard to use
If X has a mean of 10 and a standard deviation of 2, what is the standard deviation of 3X?
6
Why is a larger sample size better for confidence intervals?
It gives a smaller margin of error