AP Statistics Practice Test

These questions are part of the practice quiz. Start practicing

• What does a confidence interval provide?
• What does R-squared indicate in a regression model?
• What do residuals represent in a regression analysis?
• What is the approximate mean score for two sections of a class that took the same quiz, one with a mean of 80 and the other with a mean of 90?
• What is a true statement about bias in sampling?
• What is the purpose of a control group in an experiment?
• What issue does a chemistry professor face if he surveys only students who attend his class to improve attendance?
• What is a distribution in statistics?
• What is essential for reducing variability in an experimental design?
• If a scatterplot of 1/sqrt(y) vs. x shows a strong positive linear pattern, what can we infer about the residuals plot for the regression of y on x?
• What does a Type I error indicate?
• Which of the following variables is quantitative?
• How do you find the mode of a data set?
• If a scatterplot indicates a positive association, what would be the expected outcome for the correlation coefficient?
• Is the pooled sampling method of 250 students from three high schools a simple random sample?
• A standardized score (z-score) of +2.5 signifies what in terms of Parker's academic performance?
• Which of the following correlations best represents a negative association?
• Which of the following best describes a normal distribution?
• Why is replication important in experimental design?
• What characterizes a skewed distribution?
• What might a non-random pattern in a residuals plot suggest?
• What does covariance measure?
• Which of the following correctly describes a timeplot?
• In statistical terms, what does it mean to say that a sample is "random"?
• In an experiment comparing shampoo effects, how many factors are being considered?
• Why is it important to assess the response variable in an experiment?
• If the acidity (pH) of rainwater tested is represented by a z-score of 1.8, what does this indicate about its acidity?
• Why might a stemplot be preferred over a boxplot for displaying data?
• What does it mean when results are described as "robust"?
• How is the median determined in a dataset?
• If two groups have the same median but different ranges, what can be concluded about their distributions?
• How can researchers display rain acidity data over several decades to show trends?
• What summary statistics are affected by adding a constant to each data value?
• What is the formula for the z-score?
• If the correlation between x and y is r = 0.35 and we double each x value, decrease each y by 0.20, and interchange the variables, what is the new correlation?
• Which of the following is a common method to assess model appropriateness in regression?
• If a normal model describes the page yield of printer ink cartridges, which statement must be true?
• What does the interquartile range (IQR) represent in a dataset?
• Which of the following is not required in an experimental design?
• Which of the following is a potential drawback of observational studies?
• Which statement regarding sampling error is correct?
• In which scenario would a researcher expect to encounter non-response bias?
• How can outliers affect the interpretation of data?
• What does a high standard deviation indicate about a data set?
• What is an advantage of using a stem and leaf display over a dotplot?
• What is an observational study?
• What does it mean if the slope of a regression line is positive?
• In a study on car damage, if a car hits a barrier at a speed of 1.5 standard deviations above the mean, what can be expected regarding the damage?
• What aspect of a study is essential to determine causality?
• What type of predictive model is most useful for a farmer who increases wheat production by a consistent number of bushels each year?
• What is the standard deviation?
• What can be concluded about the survey conducted by the car dealership if only one-third of the recipients responded?
• How is sample size related to the Central Limit Theorem?
• To display the trend in the number of dogs housed by the SPCA over 20 years, which type of plot is most appropriate?
• In a regression analysis with r² = 0.72 for profits and advertising spending, what can be concluded?
• In a skewed distribution, which measure is typically affected the most?
• What effect does re-expressing data usually have on regression analysis?
• Which statement about correlation is true?
• Which option is NOT a goal of re-expressing data?
• What does the residuals plot indicate when a least squares line is fitted to a scatterplot?
• What is the purpose of a chi-square test in statistics?
• What effect does removing a point in the upper right corner of a scatterplot have on the slope of the line of best fit and the correlation?
• What does the term "null hypothesis" refer to in hypothesis testing?
• What type of data representation should be used to summarize students' test scores over time?
• Which option is an example of quantitative data?
• How is the linear correlation coefficient best described?
• In the context of an experiment, what is the primary purpose of blocking?
• What is an IQR (Interquartile Range)?
• How is "statistical significance" defined in the context of research studies?
• In a study linking weight and pulse rate, what does a positive residual indicate?
• What is the significance of a confidence level in statistics?
• When predicting a student's final grade, what does a positive residual signify?
• Which model is most appropriate for describing long-term growth in the stock market?
• Describe the role of the slope in a linear regression equation.
• A correlation of zero between two quantitative variables indicates what?
• What characteristic defines a control group in an experiment?
• When a car dealership surveys visitors who did not buy a car, which potential bias might affect the results?
• What is the purpose of a hypothesis test?
• What key information does a box plot visually represent?
• What is the significance level (alpha) in hypothesis testing?
• What does it mean for two events to be independent?
• What is the overall mean number of hours worked by a group if the mean for 30 males is 6 hours and 20 females is 9 hours?
• What is margin of error?
• Which statement about a regression line is true regarding the influence of outliers?
• What characteristic is least likely to be associated with a normal distribution?
• What figure represents the central tendency of a data set?
• What is the most likely correlation between fathers' heights and their 16-year-old sons' heights?
• Which of the following correctly defines a confounding variable?
• In the model lnh = -1.2 + 1.4(ln c), if a tree has a circumference of 60 inches, what is the height estimate of the tree according to this model?
• What conclusion can be drawn from a study that finds differing responses based on medication and climate conditions?
• What does it mean for a result to be statistically significant?
• When might re-expressing data not be necessary?
• If the point in the upper left corner of the scatterplot is removed, what will happen to the correlation (r) and the slope of the line of best fit (b)?
• From the provided ogive of veterinary bills, how can we estimate the IQR of these expenses?
• What does an r² value of 0.311 indicate in a regression analysis of college GPAs and high school GPAs?
• A company that experiences the same percentage increase in sales each year is demonstrating which kind of growth?
• Which of the following statements about correlation and fertilizer use could potentially be true?
• What is the role of randomization in experiments?
• In statistics, what does a p-value represent?
• What is the effect of a low p-value in hypothesis testing?
• What statistical tool can best describe the strength of the relationship between two variables?
• Which statement is true about the manipulation of independent variables in experiments?
• When is a scatterplot most useful in statistics?
• What is "sample proportion" in statistics?
• A basketball player has a 70% free throw percentage. What plan can be used to simulate her performance in her next five attempts?
• How is qualitative data best described?
• What can be inferred from the five-number summary of credit hours for a specific group of students?
• When two variables show a high correlation due to an external, hidden factor, this is an example of?
• What is meant by "bias" in statistical sampling?
• What information does a boxplot NOT convey about a dataset?
• In regression analysis, what does a curved residual plot typically indicate?
• Which of the following is not a source of caution in regression analysis between two variables?
• What does a higher z-score indicate about a data point in relation to the mean?
• What variable about German Shepherds is most likely to follow a normal distribution model?
• In regression, which variable is typically considered the independent variable?
• Which aspect of the flea control experiment helps ensure that results are valid?
• Which statement about correlation is true?
• What aspect of a dataset does frequency help describe?
• What does a significant p-value typically indicate in hypothesis testing?
• What is the best estimate of the standard deviation of the men's weights displayed in a dot plot?
• What does a symmetric histogram suggest about its data distribution?
• Which of the following best defines a sample?
• What is a critical factor in assuring representation in survey results?
• What is the primary utility of a residuals plot in regression analysis?
• What is the primary outcome of quantifying variance in a dataset?
• When evaluating survey methods in educational settings, what is a major flaw of voluntary response surveys?
• Which of the following statements regarding correlation is true?
• What role does hypothesis testing play in statistics?
• What is the consequence of a Type II error?
• What is a variable in statistics?
• In what context would you use a census instead of a sample?
• Which variable is most likely to follow a normal model?
• Which of the following is a key characteristic of an experiment?
• Which statement is true about the data shown in a histogram?
• Which of the following describes how bias can influence research results?
• What is the primary goal of conducting a hypothesis test?
• How do you interpret a confidence interval?
• If a Saturn has a standardized score (z-score) of +2.2 in fuel economy, what does this indicate?
• What is simple random sampling?
• If the slope of the line predicting SAT score from family income is 6.25 points per $1000, what is the slope when predicting family income from SAT score?
• What type of study is it when a researcher tracks 50 puppies without thyroid problems to observe any dietary effects over time?
• In the January 2005 Gallup Youth Survey, what is true about the finding that Napoleon Dynamite had an 8% rating among U.S. teens?
• How do you calculate the mean of a data set?
• Which best describes stratified sampling?
• Why is random assignment critical in experimental design?
• What role do outliers play in statistical data analysis?
• What type of bias occurs when certain members of a population are less likely to be included in a sample?
• Which data collected by the SPCA about dogs is categorized as categorical?
• What is a scatter plot?
• Define correlation.
• What is the overall mean speed of all the individuals ticketed by police?
• In the context of experiments, what are places used for?
• What does linear regression analysis primarily assess?
• What role does the dependent variable play in a statistical experiment?
• When is it appropriate to use a chi-square test?
• Which type of plot should one avoid when discussing gaps and clusters in a data set?
• What does statistical inference involve?
• What type of sampling requires that every member of the population has an equal chance of being selected?
• What is the predicted outcome when applying a linear regression model to a non-linear relationship?
• What design feature is used in the arthritis medication experiment to account for age differences among subjects?
• According to the model sq rt distance = 3.30 + 0.235(speed), approximately how much stopping distance is needed for a car going 65 mph?
• Which type of scatterplot indicates a strong association between two variables even if the correlation is nearly zero?
• What is the difference between descriptive and inferential statistics?
• If a student's high school GPA is 2.5 standard deviations above the mean, what college GPA can we expect based on a correlation coefficient of 0.560?
• What happens when an influential point is removed from a data set regarding the regression line?
• What does a p-value represent in statistical analysis?
• Which of the following best defines a "response variable" in research?
• What is necessary for a hypothesis test to be valid?
• What type of plot is most suitable for examining the percentage of students earning various grades?
• How does a researcher mitigate the impact of outliers on their analysis?
• Which variable is most likely to follow a normal distribution?
• Which statement describes the purpose of a null hypothesis?
• What does a p-value represent in hypothesis testing?
• If a company's sales increase by the same amount each year, what type of growth is it experiencing?
• What can be concluded when the correlation between a family's weekly income and restaurant spending is r = 0.30?
• What type of data is collected from rating scales (e.g., 1 to 5)?
• The study where 100 non-exercising men are compared with 100 exercising men is known as what type of study?
• Which sampling technique is most likely to introduce bias?
• How does the experimental design with dogs and cats help address variability in a flea control study?
• If your test score is the 3rd quartile for the class, what can be inferred?
• What does a high standard deviation indicate about a dataset?
• What does a high variance indicate about a dataset?
• Why is the standard deviation a critical measure in statistics?
• What role does randomization play in an experiment?
• In experimental design, what is the primary purpose of blinding?
• What distinguishes a population from a sample in statistics?
• A company sponsoring a new internet search engine wants to collect data on the ease of using it. Which is the best way to collect the data?
• What is the relationship between variance and standard deviation?
• Which measure would not change if a constant is added to every data value?
• In the context of a linear regression, what does the term "residual" refer to?
• What type of variable does a t-test typically compare?
• What characteristic distinguishes a randomized block design?
• Why is double blinding important in experiments?
• What does the Central Limit Theorem state?
• What issue arises with the battery experiment when comparing products from different brands?
• Is the method of testing two wrestlers from each high school team a simple random sample?
• What is a key characteristic of ordinal data?
• Explain the term "outlier."
• What is the expected correlation coefficient between hours awake and hours asleep over a 24-hour period?
• In a linear model estimating the cost of an HDTV based on screen size, what is the most likely value of the slope of the line of best fit?
• What does the term "frequency" refer to in data?
• What is the best method to collect data on the average ages of math and science teachers?
• What is the purpose of conducting a survey in statistics?
• In an experiment testing pain relievers, what is the primary variable being manipulated?
• What can be inferred about a distribution that is skewed to the right?
• What does a high margin of error in estimation imply?
• Which method can simulate the selection of rotten eggs from a dozen when three of them are rotten?
• In a properly designed experiment, what is the purpose of random assignment?
• Explain "statistical power."
• What is the most likely standard deviation of data displayed in the given dot plot?
• What is meant by "experimenter bias"?
• What population of interest is being considered in the magazine subscriber survey?
• What information does the standard deviation provide about a dataset?
• What characterizes a normal distribution?