Top 200 Vocabulary Word List for AP Statistics | Must Know Words for Common Examination Instructions

The 200-word examination instruction list

AP Statistics instructions tell you whether to describe data, explain how they were collected or draw a conclusion from an inference procedure. Name the population, parameter or group when it matters. A correct computation still needs an interpretation when the prompt asks what the result means.

This study bank includes prompt words, response formats and terms that help you interpret the task. Check the official directions for the particular question and exam year.

Exam requirements · Worked examples · Fencing Method

Statistical design, inference and exam directions

No.	Instruction or term	What it asks you to do
1	Investigative question	Ask a focused question that can be answered with data.
2	Identify the population	Name the full group to which the study is intended to refer.
3	Identify the parameter	Name the numerical characteristic of the population in context.
4	Identify the statistic	Name the numerical summary computed from the sample.
5	Sample versus census	Check whether data come from part of the population or every member.
6	Random sampling	Use the sampling method to decide which population the result can represent.
7	Random assignment	Use the assignment procedure to assess whether treatment groups support a causal conclusion.
8	Observational study	Check what researchers observed and which causal conclusions the design cannot establish by itself.
9	Completely randomized design	Explain how the experimental units are randomly assigned to the treatments.
10	Blocking	Group similar units before randomly assigning treatments within each block.
11	Matched pairs	Compare matched units or the same unit under two conditions and analyse the differences.
12	Stratified sample	Sample from each stratum according to the stated design.
13	Cluster sample	Select groups and use the sampling procedure specified for units within them.
14	Undercoverage	Identify which members of the population the sampling frame misses.
15	Nonresponse	Explain how those who do not respond may differ from those who do.
16	Describe the distribution	Discuss relevant shape, centre, spread and unusual values in context.
17	Compare distributions	Use the same features for each group and compare them explicitly.
18	Interpret the slope	Give the predicted change in response per one unit increase in the explanatory variable.
19	Interpret the intercept	Explain the predicted response at zero if zero makes sense in context.
20	Residual	Subtract the predicted response from the observed response.
21	Conditional distribution	Use the named group as the denominator.
22	Sampling distribution	Describe the behaviour of a statistic across repeated samples under the stated model.
23	Standard error	Use an estimated standard deviation of the sampling distribution of a statistic.
24	Check conditions	Name the required conditions for the procedure and connect them to the study.
25	Select the inference procedure	Match the procedure to the parameter, design and question.
26	State the hypotheses	Write the null and alternative claims about the population parameter.
27	Interpret the p-value	Under the null hypothesis, describe the probability of a result at least as extreme in the direction or directions specified.
28	Decision at the stated level	Compare the p-value with the stated significance level.
29	Conclusion in context	Translate the inference decision into a statement about the original question.
30	Confidence interval	Give the plausible range for the population parameter under the stated method and conditions.
31	Interpret the confidence level	Explain the long-run success rate of the interval procedure in repeated sampling.
32	Margin of error	Identify the amount added to and subtracted from the point estimate in the stated interval.
33	Statistical significance	Use the test decision without assuming a large or important effect.
34	Practical significance	Judge whether the estimated difference matters in the setting.
35	Type I error	Describe rejecting a true null hypothesis in the situation.
36	Type II error	Describe failing to reject a false null hypothesis in the situation.
37	Regression prediction	Use the fitted relationship to estimate the response for a stated input.
38	Difference in proportions	Keep the groups and subtraction order consistent with the question.
39	Fully digital	Complete both parts in Bluebook for the May 2027 AP Statistics exam.
40	Interpret versus compute	Explain what the numerical result means when the question asks for interpretation.
41	Median and interquartile range	Compare the middle value and the width of the middle half in the named groups.
42	Resistant measure	Choose a summary that is relatively insensitive to extreme observations.
43	Skewed right	Identify a distribution with a longer tail toward higher values.
44	Side-by-side boxplots	Compare corresponding medians, quartiles and spreads on the same scale.
45	Scatterplot	Describe form, direction, strength and unusual points when relevant.
46	Least-squares line	Use the fitted line that minimises the sum of squared residuals.
47	Extrapolation	Recognise when the requested prediction is outside the observed input range.
48	Coefficient of determination	Explain the proportion of response variability accounted for by the fitted model.
49	Mutually exclusive events	Check whether the events can occur together.
50	Independent events	Check whether knowing one event occurred changes the probability of the other.
51	Conditional probability	Restrict the sample space to cases satisfying the condition.
52	Binomial model	Check the fixed number of independent trials, two outcomes and constant success probability.
53	Expected count	Compute the count predicted under the stated model.
54	Pooled estimate	Use the combined estimate when the procedure assumes a common proportion.
55	Null value	Identify the parameter value or relationship stated under the null hypothesis.
56	Alternative direction	Use the direction specified by the research question.
57	Fail to reject	State that the evidence is insufficient to reject the null under the procedure.
58	Power	Give the probability of rejecting a false null under a specified alternative.
59	Paired differences	Subtract observations within each pair in the same order before analysis.
60	Difference versus association	Distinguish a numerical group contrast from an inference about the relationship.

Data, probability and comparisons

No.	Instruction or term	What it asks you to do
61	Data-Based and Statistical Reasoning	Use the relevant figures and statistical meaning before drawing a conclusion.
62	Model prediction	Find what the proposed explanation would lead you to expect under the stated conditions.
63	Positive control	Use the comparison expected to show that the procedure can detect an effect.
64	Negative control	Use the comparison expected to show what happens without the target effect.
65	Baseline measurement	Use the reading taken before the stated intervention or change.
66	Experimental readout	Identify what the reported measurement actually indicates.
67	Experimental manipulation	Identify what investigators deliberately changed.
68	Selection bias	Check whether the way participants were included affects the comparison.
69	Alternative hypothesis	Identify a different explanation or prediction the study could test.
70	Control for	Account for a factor that could otherwise distort the comparison.
71	Statistically significant	Interpret the result under the test and threshold supplied, alongside the effect and uncertainty.
72	Identify the reference group	Find the comparison used to isolate the change attributed to the intervention.
73	Identify the independent variable	Name the factor manipulated or selected as input.
74	Identify the dependent variable	Name the outcome that was measured.
75	Sample mean	Use the average of the values in the specified sample.
76	Control treatment	Use the treatment intended to provide a reference comparison.
77	Experimental design	Use the stated groups, conditions and measurements to judge the experiment.
78	Sample size	Check how many observations or individuals contribute to the result.
79	Controlled variable	Identify a factor kept constant to help isolate the tested relationship.
80	Raw data	Use the measurements as originally collected.
81	Processed data	Use values calculated, combined or transformed from the original readings.
82	Percentage uncertainty	Express the uncertainty relative to the measured value as a percentage.
83	Validity	Consider whether the evidence or method answers the intended question.
84	Representative sample	Check whether the selected cases reflect the population of interest.
85	Model	Use a simplified mathematical or conceptual representation to address the task.
86	Rate of change	Find the change in one quantity per unit change in another.
87	Best illustrates	Choose the example or quotation that most directly shows the idea.
88	Textual evidence	Choose a detail from the source that supports the precise claim.
89	Compare	Set the items side by side on the same relevant feature.
90	Illustrate	Make an idea clear with a relevant example or diagram.
91	Demonstrate	Show how a fact, process or result can be established.
92	Estimate	Find an approximate answer using the available clues.
93	Group	Put items with a shared feature together.
94	Evidence	A fact, detail or observation that supports a claim.
95	Condition	A requirement that must be satisfied.
96	Give an exact value	Use a form that preserves the full mathematical value.
97	Measure	Take the required reading from a diagram or scale when the task permits it.
98	Check the distribution display	Use the plotted values and labels rather than the visual impression alone.
99	Estimate from a graph	Use the scale and plotted information to obtain a sensible approximate value.
100	Compare the distributions	Use corresponding measures of location or spread as the question asks.
101	Does the data support the statement	Calculate or identify the relevant measures and use them to make a judgment.
102	Choose an appropriate display	Match the display to the variable type and comparison.
103	Estimate the mean from grouped data	Use class midpoints and frequencies to estimate the total and divide by the total frequency.
104	Independence condition	Use the design and procedure to justify treating the relevant observations as independent.
105	Relative frequency estimate	Use the observed proportion as the estimated probability when the task asks for it.
106	Combined mean	Use total values and sample sizes to find the mean across the groups.
107	Percentage within a group	Use only the stated group as the denominator.
108	Conditional proportion	Divide the count with the outcome by the total in the specified condition.
109	Most appropriate statistic	Choose a numerical summary that suits the question and distribution.
110	Use the scale of the display	Check axis intervals and group labels before comparing.
111	Read the quartiles	Locate the values separating the ordered data into quarters.
112	Estimate the median	Use the midpoint of the ordered data or the appropriate position on a grouped display.
113	Calculate a rate	Divide the relevant change or quantity by the appropriate time or other denominator.
114	Calculate the percentage change	Divide the change by the starting value and multiply by 100.
115	Exact value	Leave the answer in a form that preserves its full value.
116	Independent variable	Identify what the investigator changes deliberately.
117	Dependent variable	Identify the measured outcome of the investigation.
118	Control variable	Identify what should be kept constant for a fair comparison.
119	Measurement	Read or calculate a quantity and report the appropriate unit.
120	Estimate from the graph	Use the plotted trend to obtain a sensible approximate value.
121	Find the exact value	Retain radicals, fractions, logarithms or π in exact form where appropriate.
122	Identify the feature of the graph	Use the graph or equation to decide what the named point represents.
123	Expected value	Find the probability-weighted mean under the stated model.
124	Compare and contrast	Address similarities and differences for the named items.
125	Variable	Identify a quantity or feature that can change.
126	One possible value	Supply a single value that satisfies the given conditions.
127	Unit rate	Calculate the amount corresponding to one unit of the other quantity.
128	Percentage point	Find the simple difference between two percentage values.
129	Initial value	Find the starting quantity, often the output at input zero.
130	Probability	Find the likelihood of the event under the given conditions.
131	Random sample	Check how cases are selected before drawing conclusions about a population.
132	Necessary condition	Identify what must hold whenever the stated outcome holds.
133	Sufficient condition	Identify what guarantees the stated outcome.
134	Invalid step	Find the specific transformation or inference that does not follow.
135	Range of values	Find all possible outputs under the stated restrictions.
136	Calculate a sample proportion	Divide the number meeting the condition by the relevant sample size.
137	Expected cell counts	Check that the expected counts meet the condition for the stated chi-square procedure.
138	Absolute value	Use the distance from zero or separate cases based on the expression’s sign.
139	Compare two proportions	Use the correct denominators and report the direction of the contrast.
140	Effect of an outlier	Explain how an extreme value affects the requested statistic or fitted relationship.
141	Identify a control	Name the comparison condition relevant to the claim being tested.
142	Construct a graph	Set up the axes, scale and labels, then represent the data in the requested form.
143	Plot the data	Place the values on the graph in the correct positions.
144	Inference from the sample	State the conclusion about the named population parameter that the data support.
145	Evidence from the study	Use the relevant comparison or numerical result from the stated study.
146	Corroborate	Compare sources to see where one supports another’s account.

Evidence and answer checks

No.	Instruction or term	What it asks you to do
147	Recognise	Find a familiar feature in a new example.
148	Identify	Name or pick out the item the question specifies.
149	Select	Choose only the number of options requested.
150	Match	Pair each item with the option that corresponds to it.
151	Complete	Fill in what is missing while keeping the supplied structure.
152	Label	Attach the correct name to the indicated part.
153	Locate	Find the specified detail, point or region.
154	Indicate	Make the chosen feature or answer clear.
155	Record	Write the result in the space and form provided.
156	Answer	Respond directly to the question being asked.
157	Give	Supply the requested fact, example or result.
158	State	Express the required point directly and clearly.
159	Name	Supply the correct term, person or item.
160	List	Set out the requested items separately.
161	Define	Give the precise meaning used in the subject or question.
162	Describe	Report the relevant characteristics, events or pattern.
163	Outline	Give the main steps or points in brief.
164	Summarise	Select the central points and leave out minor details.
165	Explain	Connect the result to its cause, mechanism or reasoning.
166	Contrast	Show how the items differ on a shared point of comparison.
167	Analyse	Break down the evidence and explain how its parts relate.
168	Interpret	Say what a statement, result or display means in context.
169	Infer	Use clues to reach a conclusion the material implies.
170	Predict	Use available evidence to say what is likely to happen.
171	Suggest	Offer a plausible answer suited to the information given.
172	Justify	Give evidence for the claim and explain how that evidence supports, qualifies or defends it.
173	Evaluate	Weigh relevant evidence or criteria before reaching a judgment.
174	Assess	Judge the extent, value or strength of something using evidence.
175	Discuss	Develop a structured response that considers the relevant issues.
176	Distinguish	Give the feature that lets the reader tell two things apart.
177	Support	Supply evidence that helps establish the claim.
178	Determine	Work from the given information to establish an answer.
179	Calculate	Use numbers or other given information to work out a result.
180	Check	Test the answer against the original instruction or condition.
181	Arrange	Put items into the order or grouping requested.
182	Sequence	Put stages into a meaningful order.
183	Classify	Assign each item to a category using the stated rule.
184	Order	Sort items by the criterion given in the prompt.
185	Omit	Leave out the indicated item or detail.
186	Include	Make sure the requested part appears in the response.
187	Exclude	Keep the named item or category outside your answer.
188	Refer to	Use the specified passage, figure or notes when responding.
189	Based on	Ground the answer in the material named in the question.
190	According to	Use what the specified source says.
191	In context	Use the meaning that fits this passage or situation.
192	Most likely	Choose the conclusion with the strongest support among the options.
193	Best supported	Prefer the conclusion backed most directly by the evidence.
194	Explicit	Stated directly in the source.
195	Implicit	Suggested by the source and recoverable from clues.
196	Claim	An assertion that can be tested against evidence or reasoning.
197	Example	A particular case used to make a general idea clear.
198	Conclusion	The result reached after considering the reasoning or evidence.
199	Assumption	A premise taken as given for the purpose of the question.
200	Constraint	A restriction that shapes the possible answers.

What the examination requires

May 2027 is fully digital

College Board lists 42 multiple-choice questions and four free-response questions. Each section lasts 90 minutes and contributes 50% of the exam score. Both sections are completed in Bluebook. The May 2027 format replaces the earlier hybrid format and uses four options per multiple-choice question.

Practise the revised framework

College Board revised the course for 2026–27 and added investigative questions. Use the current course description to check scope before using older papers. The 2027 format includes a free-response question on inference and questions that combine multiple statistical practices.

Check calculator and notation rules

College Board allows approved handheld graphing calculators and provides the built-in Desmos graphing calculator in Bluebook. Use the official digital response guidance to practise entering notation. Where a result comes from software, connect the output to the study and the method the prompt asks you to use.

The College Board Advanced Placement programme is based in the United States and its exams are also offered internationally. Check arrangements with your exam centre and confirm credit or placement policies with the institution that will receive your score.

Worked examples of common examination instructions

Use these original examples to see how the wording changes the answer you need to give.

Separate generalisation and causation

A school randomly selects 100 students from its roster and asks how long they sleep. A suitable sampling method can support an inference about the school population. A survey of existing habits does not establish that a particular habit caused an outcome. Random assignment of treatments in an experiment addresses a different question.

Interpret a p-value in context

An invented experiment reports p = 0.03 for a one-sided test about whether a new method increases mean output. If the null hypothesis holds and the procedure’s conditions apply, the probability of a result at least as favourable to the alternative as the observed result is 0.03. The p-value does not give the probability that the null hypothesis is true.

Report a comparison and its units

One group has a median waiting time of 12 minutes and another has a median of 17 minutes. The second group’s median is five minutes higher. If the question asks about spread too, use an appropriate measure for both groups. The medians alone do not describe the variation.

Use the Fencing Method to practise instructions

Start with a short, accurate answer. Add a precise detail, then explain the relationship or evidence the prompt calls for. Apply the same instruction to a fresh example.

1. Group B waited longer at the median.
2. Group B’s median wait was five minutes longer.
3. Group B’s median wait was 17 minutes, compared with 12 minutes for Group A.
4. Use a second set of data. Add a paired comparison of spread if the question asks for it.

Read the eduKate Fencing Method for Vocabulary.

Practise and check your answers

After a practice inference, locate your parameter, procedure, conditions, result and conclusion. Use words that identify the population and direction of the claim. Practise typing the conclusion and checking any notation in the official digital preview.

Use one display to ask for a centre, a spread and a comparison across groups. A single number can answer one of those questions but leave the others open. Match your response to the exact wording.

Frequently asked questions

How many free-response questions are in May 2027?

College Board lists four, in a 90-minute section completed in Bluebook.

Does random sampling establish causation?

Random sampling helps address generalisation. Look at treatment assignment and the design when judging causation.

Does a small p-value show a large effect?

Check the estimated size and practical context separately from the significance decision.

Official sources and next reading

• College Board AP Statistics exam format
• AP Statistics released exam questions and scoring guidance
• AP Statistics revisions for 2026–27

Related guide · MCAT scientific evidence and study interpretation

Read eduKateSG’s 200-word vocabulary guide for more ways to group and practise vocabulary.

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