Marlbridge guide to AP® Statistics

Unit roadmap

Units and topics exactly as numbered in the 2026–27 Course and Exam Description. Weightings are the official multiple-choice ranges. Marlbridge has written resources for 55 of 55 topics so far; the rest are planned and marked as such.

1. Unit 1: Exploring One-Variable Data and Collecting Data 20–30% of multiple choice · 13 topics

   • 1.1 Introducing Statistics: What Can We Learn from Data? Study guideRevision notesPractice questionsTopic checklist
   • 1.2 Variables Study guideRevision notesPractice questionsTopic checklist
   • 1.3 Tabular Representation and Summary Statistics for One Categorical Variable Study guideRevision notesPractice questionsTopic checklist
   • 1.4 Graphical Representations for One Categorical Variable Study guideRevision notesPractice questionsTopic checklist
   • 1.5 Graphical Representations for One Quantitative Variable Study guideRevision notesPractice questionsTopic checklist
   • 1.6 Descriptions for One Quantitative Variable Distributions Study guideRevision notesPractice questionsTopic checklist
   • 1.7 Summary Statistics for One Quantitative Variable Study guideRevision notesPractice questionsTopic checklist
   • 1.8 Graphical Representations of Summary Statistics for One Quantitative Variable Study guideRevision notesPractice questionsTopic checklist
   • 1.9 Comparisons of the Distributions for One Quantitative Variable Study guideRevision notesPractice questionsTopic checklist
   • 1.10 The Investigative Question Revisited and Data Collection Study guideRevision notesPractice questionsTopic checklist
   • 1.11 Random Sampling Study guideRevision notesPractice questionsTopic checklist
   • 1.12 Potential Problems with Sampling Study guideRevision notesPractice questionsTopic checklist
   • 1.13 Experimental Design Study guideRevision notesPractice questionsTopic checklist
   • Exploring One-Variable Data and Collecting Data: Unit Diagnostic (Statistics Unit 1)
   • Exploring One-Variable Data and Collecting Data: Mixed Unit Review (Statistics Unit 1)
2. Unit 2: Probability, Random Variables, and Probability Distributions 15–25% of multiple choice · 12 topics

   • 2.1 Tabular and Graphical Representations for the Distributions of Two Categorical Variables Study guideRevision notesPractice questionsTopic checklist
   • 2.2 Summary Statistics for Two Categorical Variables Study guideRevision notesPractice questionsTopic checklist
   • 2.3 Estimating Probabilities Using Simulation Study guideRevision notesPractice questionsTopic checklist
   • 2.4 Introduction to Probability Study guideRevision notesPractice questionsTopic checklist
   • 2.5 Mutually Exclusive Events Study guideRevision notesPractice questionsTopic checklist
   • 2.6 Conditional Probability Study guideRevision notesPractice questionsTopic checklist
   • 2.7 Independent Events and Unions of Events Study guideRevision notesPractice questionsTopic checklist
   • 2.8 Introduction to Random Variables and Probability Distributions Study guideRevision notesPractice questionsTopic checklist
   • 2.9 Parameters of Random Variables Study guideRevision notesPractice questionsTopic checklist
   • 2.10 The Binomial Distribution Study guideRevision notesPractice questionsTopic checklist
   • 2.11 The Normal Distribution Study guideRevision notesPractice questionsTopic checklist
   • 2.12 Sampling Distributions and the Central Limit Theorem Study guideRevision notesPractice questionsTopic checklist
   • Probability, Random Variables and Probability Distributions: Unit Diagnostic (Statistics Unit 2)
   • Probability, Random Variables and Probability Distributions: Mixed Unit Review (Statistics Unit 2)
3. Unit 3: Inference for Categorical Data: Proportions 15–25% of multiple choice · 15 topics

   • 3.1 Estimators Study guideRevision notesPractice questionsTopic checklist
   • 3.2 Sampling Distributions for Sample Proportions Study guideRevision notesPractice questionsTopic checklist
   • 3.3 Constructing a Confidence Interval for a Population Proportion Study guideRevision notesPractice questionsTopic checklist
   • 3.4 Justifying a Claim Based on a Confidence Interval for a Population Proportion Study guideRevision notesPractice questionsTopic checklist
   • 3.5 Setting Up a Test for a Population Proportion Study guideRevision notesPractice questionsTopic checklist
   • 3.6 p-Values Study guideRevision notesPractice questionsTopic checklist
   • 3.7 Carrying Out a Test for a Population Proportion Study guideRevision notesPractice questionsTopic checklist
   • 3.8 Potential Errors When Performing Tests Study guideRevision notesPractice questionsTopic checklist
   • 3.9 Sampling Distributions for the Difference Between Sample Proportions Study guideRevision notesPractice questionsTopic checklist
   • 3.10 Constructing a Confidence Interval for the Difference Between Two Population Proportions Study guideRevision notesPractice questionsTopic checklist
   • 3.11 Justifying a Claim Based on a Confidence Interval for the Difference Between Two Population Proportions Study guideRevision notesPractice questionsTopic checklist
   • 3.12 Setting Up a Test for the Difference Between Two Population Proportions Study guideRevision notesPractice questionsTopic checklist
   • 3.13 Carrying Out a Test for the Difference Between Two Population Proportions Study guideRevision notesPractice questionsTopic checklist
   • 3.14 Setting Up a Chi-Square Test for Homogeneity or Independence Study guideRevision notesPractice questionsTopic checklist
   • 3.15 Carrying Out a Chi-Square Test for Homogeneity or Independence Study guideRevision notesPractice questionsTopic checklist
   • Inference for Categorical Data: Proportions: Unit Diagnostic (Statistics Unit 3)
   • Inference for Categorical Data: Proportions: Mixed Unit Review (Statistics Unit 3)
4. Unit 4: Inference for Quantitative Data: Means 10–20% of multiple choice · 10 topics

   • 4.1 Sampling Distributions for Sample Means Study guideRevision notesPractice questionsTopic checklist
   • 4.2 Constructing a Confidence Interval for a Population Mean or Population Mean Difference Study guideRevision notesPractice questionsTopic checklist
   • 4.3 Justifying a Claim Based on a Confidence Interval for a Population Mean or Population Mean Difference Study guideRevision notesPractice questionsTopic checklist
   • 4.4 Setting Up a Test for a Population Mean or Population Mean Difference Study guideRevision notesPractice questionsTopic checklist
   • 4.5 Carrying Out a Test for a Population Mean or Population Mean Difference Study guideRevision notesPractice questionsTopic checklist
   • 4.6 Sampling Distributions for the Difference Between Two Sample Means Study guideRevision notesPractice questionsTopic checklist
   • 4.7 Constructing a Confidence Interval for the Difference Between Two Population Means Study guideRevision notesPractice questionsTopic checklist
   • 4.8 Justifying a Claim Based on a Confidence Interval for the Difference Between Two Population Means Study guideRevision notesPractice questionsTopic checklist
   • 4.9 Setting Up a Test for the Difference Between Two Population Means Study guideRevision notesPractice questionsTopic checklist
   • 4.10 Carrying Out a Test for the Difference Between Two Population Means Study guideRevision notesPractice questionsTopic checklist
   • Inference for Quantitative Data: Means: Unit Diagnostic (Statistics Unit 4)
   • Inference for Quantitative Data: Means: Mixed Unit Review (Statistics Unit 4)
5. Unit 5: Regression Analysis 10–20% of multiple choice · 5 topics

   • 5.1 Graphical Representations Between Two Quantitative Variables Study guideRevision notesPractice questionsTopic checklist
   • 5.2 Correlation Study guideRevision notesPractice questionsTopic checklist
   • 5.3 Linear Regression Models Study guideRevision notesPractice questionsTopic checklist
   • 5.4 Residuals Study guideRevision notesPractice questionsTopic checklist
   • 5.5 Least-Squares Regression Study guideRevision notesPractice questionsTopic checklist
   • Regression Analysis: Unit Diagnostic (Statistics Unit 5)
   • Regression Analysis: Mixed Unit Review (Statistics Unit 5)

Exam skills

Guides that apply across every unit: what each task verb asks you to do, and how to set out answers so every step of your reasoning is visible.

• Communicating Statistics: Context, Conditions and Conclusions: Exam Skills Guide (Statistics)

  How to describe data in context, name and check conditions, set out inference in four steps and write conclusions about intervals, tests and regression without overclaiming.

• Task Verbs and Free-Response Technique: Exam Skills Guide (Statistics)

  What each free-response task verb asks for in statistics answers, how much to write, how to read a multi-part question, plan your time and show work, with original examples.

Statistical practices

1. Formulate Questions

Determine a valid investigative question that requires a statistical investigation.

2. Collect Data

Identify and justify methods for collecting data and for statistical inference.

3. Analyze Data

Construct representations of data and calculate statistical outputs.

4. Interpret Results

Interpret results and justify conclusions and methods.