# AP Statistics

Semester 1 Exam Study Guide

The exam will be on Wednesday, December 16, 2020.

The content of the Semester 1 Exam includes everything from Chapter 8 back to "Big Bird's Big Book of Numbers" (see the list of topics below). There will be 21 multiple choice questions (designed to be answered in 40 minutes), and 5 Free response questions (designed to be answered in 50 minutes).

You are provided a Formula Sheet that also has tables for the Normal, T, and Chi-Square distributions.

The College Board that administers the AP exam has this helpful passage about what should be included in a free response question:

Show all your work. Indicate clearly the methods you use, because you will be scored on the correctness of your methods as well as on the accuracy and completeness of your results and explanations.

Here is a check list of some major topics from the first few chapters:

• Chapter 1: Individuals, Categorical and Quatitive variables, distribution, center, spread, normal distribution, geometric distribution, histogram, stem plots, time plot, box plot symetric skewed outlier center spread and shape of a distribution, 5 number summary, mean, standard deviation, median, Q1, Q3, IQR (2016-1, 2015-1, 2013-6 2012-3a)
• Chapter 2: Density Curves and the Normal Distribution Inflection Points, percentile, z-score, transforming data, 68-95-99.7 Rule, Standard Normal N[0,1], z-scores (again), Calculations, Assessing Normality of a Distribution. (2009-2, 2013-3, 2011-1)
• Chapter 3: Scatterplots, Correlation, Regression Line (LSRL), r, r2, Residuals, Residual Plots, , Std Dev of the residual, Influential Observations, Lurking Variables (2016-6, 2015-5, 2014-6)
• Chapter 4: Experimental Units, confounding, random assignment and selection, double-blinding, block design, placebo effect, scope of inference, informed consent, confidentiality. (2016-3, 2015-6, 2014-4, 2013-2, 2011-3)
• Chapter 5: Randomness, Probability and Simulation, Probability, Law of Large Numbers, Sample Space, Probability Model, Conditional Probability, Independence.
• Chapter 6: Discrete Random Variables, Continuous Random Variables, Probability Distribution, mean (expected value) of a random variable, variance and std dev of a random variable, Linear Transformations (360, 361, 362), mean and variance of sum of random variables (365, 367), mean and variance of difference of random variables (371), Independent random variable definition (365), Binomial Setting (383), Binomial formulas (387, 388, 391), Sampling without replacement condition (394), Normal Approximation for Binomial (395), Geometric Setting (397), Geometric Formulas (399, 401).
• Chapter 7: Parameter vs Statistic, Sampling Variability, Sampling Distribution vs Population Distribution, Unbiased Estimator (421), Why n-1? (423), Bias vs Variability of a Statistic(425ff),Mean and Std Dev of a sample proportion (436), Mean and Std Deviation of a Sample Mean (444), Sample mean from a Normal Population (447), Central Limit Theorem (Sample mean from even Non-Normally distributed distributions)-(450-451)
• Chapter 8: Estimating with confidence, Confidence interval Estimating proportions and mean, t-distribution, SE
• Observational Studies topics including: The evil "Convenience Sample", The Statistical four-letter-word: bias, The wicked "Voluntary response Sample," The Golden "SRS" ( the vaccine against bias), The use of the random digit table, Stratified Random sample, Cluster Sample, the bane of undercoverage and nonresponse (221-2) and the loathsome "Wording Bias"
• Experimental Design topics including Lurking Variables and Confounding, Treatment Experimental Units and Subjects, Random Assignment (rather than selection), Completely Randomized Design, Control, Random Assignment and Replication, Double Blind and Statistical Significance, Blocking, Matched Pairs Design.

Review your work and note what you did well, correct your mistakes, and practice the topics you feel you haven't mastered.

The actual AP Exam on Thursday May 15, 2020 at 12 noon has two sections: Multiple Choice (50%) and Free Response (50%). Section I is 40 multiple choice questions designed to be answered in 90 minutes. Section II part A is 5 questions designed to be answered in 65 minutes, and part B, a single question designed to be answered in 25 minutes.