Sampling & Experiments
Interpretations
Important Things You May Have Forgotten
Probability Rules!
Name that Test!
100
Neither the subject nor those who measure the reponse variable know which treatment a subject received.
What is a double-blind experiment?
100

Write the Conclusion based on the P-value = 0.001, with 5% Significance

What is "since the P-value is less than any reasonable significance level, we reject the null hypothesis, and conclude there is significant evidence to support the alternative hypothesis"?

100
How to identify outliers for univariate data
What is Q1 - 1.5(IQR) and Q3 + 1.5(IQR)?
100
The rule for finding the probability of rolling a fair die three times and getting three fours.
What is P(rolling three 4s) = P(4)*P(4)*P(4) = P(4)^3?
100

A researcher claims that more than 60% of high school seniors use social media for more than 3 hours per day. A random sample of seniors is surveyed to test this claim.


What is a One Proportion Z-Test

200
A common form of blocking for comparing just two treatments.
What is matched pairs?
200

Interpret the slope in the least-squares regression line, y = 15 - 4x

What is "For every one unit increase in the explanatory variable, there is a predicted 4 unit decrease in the reponse variable"?

200
The expected value of a discrete random variable
What is the mean of the random variable found by summing the products of the values of x and their repsective probabilities?
200
The rule for the probability of pulling a red or queen from a standard deck of cards.
What is P(red or queen) = P(red) + P(queen) - P(red and queen)?
200

A group of students takes a practice SAT test, then completes a 6-week prep course, and takes a second practice test. The teacher wants to know if the prep course improves scores.


What is a Matched-Pairs T-Test

300
When some groups in the population are left out of the process of choosing a sample
What is undercoverage?
300
A z-score of -3.45
What is "The data value is 3.45 standard deviations below the mean"?
300
How to determine if two events, A and B, are independent
What is P(B|A) = P(B) or P(A and B) = P(A)P(B)?
300

The rule for finding the probability picking a heart given the card is a king.

What is P(Heart|King) = P(Heart and King)/P(King)

300

A high school conducts a study to investigate whether getting at least 8 hours of sleep is associated with higher academic performance. Students are randomly selected and asked whether they typically get at least 8 hours of sleep on school nights (Yes/No). Their GPA category is also recorded as High (3.5 or above) or Not High (below 3.5).

The data are summarized in a two-way table.

What is a Chi-Square test for Independence

400
The population is divided into groups. Some groups are randomly selected and all individuals in the chosen groups are sampled.
What is cluster sampling?
400

What does it mean to be 95% Confident?

What is "95 out of 100 intervals of the same sample size will contain the true parameter"

400
The standard deviation of the difference between two random variables.
What is the square root of the sum of the variances of the two random variables?
400
The rule for finding the probability of obtaining the first success on the 5th trial.
What is P(X=5) = p(1-p)^4
400

An AP Statistics teacher compares the average number of hours studied per week between students who take the class in the fall semester and those who take it in the spring semester. The two groups consist of different students.


What is a 2 Sample T-Test

500
The effects of two variables on the response cannot be distinguished from each other.
What is confounding?
500
The 95% confidence interval (-4.25, -1.33) for the difference of two means (mean #1 - mean #2).
What is "With 95% confidence, we estimate that mean #1 is between 4.25 and 1.33 units less than mean #2"
500
The mean and standard deviation of the sampling distribution of sample means
What is the mean of the sampling distribution of sample means is equal to the population mean and the standard deviation of the sampling distribution of sample means is equal to the population standard deviation divided by the square root of the sample size?
500
The rule for finding 10 successes in 15 trials.
What is P(X=10) = (15 C 10)*p^10*(1-p)^5
500

A high school cafeteria manager claims that the distribution of students choosing pizza, sandwiches, salads, and hot meals is the same as last year. A random sample of students is surveyed to compare this year’s preferences to last year’s known distribution.

What is a Chi-Square Test for Goodness of Fit

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