AP Statistics Study Guide

The coefficient of determination for the scatter plot pictured is approximately...(More than one answer may apply) https://files.catbox.moe/vye3yw.PNG

0.88 or 0.65 (choosing just 0.88 has been right previously)

The Mars candy company starts a marketing campaign that puts a plastic game piece in each bag of M&Ms. 40% of the pieces show the letter "M," 10% show the symbol "&," and the rest just say "Try again." When you collect a set of three symbols "M," "&," and "M" you can turn them in for a free bag of candy. Suppose you want to estimate how many bags will a consumer have to buy to get a free one. Let's use a simulation to find out. Use 0-9 M: 0-3 &: 4 Try again: 5-9 57821 76309 63508 29418 13026 34993 54636 17877 00987 23401

17 bags (may be 18 if that's an option)

The Department of Traffic Safety wants to reduce the number of drivers who speed on a certain stretch of road. In an attempt to reduce repeat offenders, the Department of Traffic Safety will randomly select 5 drivers, without replacement, from a population of 50 drivers convicted of speeding in order to assess the effectiveness of a new "safe driving" program. If the drivers are labeled 01, 02, 03, ..., 50 and the following line is from a random number table 22368 46573 25595 85393 30995 89198 27982 53401 93965 34095 52666 19174 Which one of the following represent the sample of 5, starting from the left end of the table?

22, 36, 25, 30, 27

After simulating the spread of a disease, a researcher wrote, "24% of the people contracted the disease." What should the correct conclusion be? (Give this some thought before responding)

24% of the people may contract the disease.

In order to plan the design of a school spirit shirt, the student council conducted a survey. They asked students which color they prefer (blue, white, maroon) and which type of shirt (t-shirt, sweatshirt). The table summarizes the responses. What percent of those who prefer sweatshirts chose maroon? https://files.catbox.moe/cqhdts.PNG

28.6%

The mean age of 12 of the members attending a mathematics department faculty meeting is 37. Mr. Smith, who is 50, arrives late. What is the average of all 13 members?

38

The following stemplot displays the weights (in pounds) of a random sample of 20 men. What is the interquartile range of this data? https://files.catbox.moe/lggql8.PNG

40 pounds

Students in a political science course were asked to describe their politics as "Liberal", "Moderate", or "Conservative." Here are the results: Liberal Moderate ConservativeFemale 38 41 11Male 51 48 20What percent of the class considers themselves to be "liberal"?

42.6%

A local bridge club has 120 members. A cumulative relative frequency graph of their ages is shown in the figure below. Approximately how many of the bridge club members are more than 80 years of age. https://files.catbox.moe/jtaru9.PNG

48

A survey of autos parked in student and staff lots at a large university were classified by country of origin, as seen in this table .Country of Origin DRIVER Student Staff American 94 81 European 38 22 Asian 66 53 What percent of the staff drove American cars?

52%

Foresters use regression to predict the volume of timber in a tree using easily measured quantities such as diameter. Let y be the volume of timber in cubic feet and x be the diameter in feet (measured at 3 feet above ground level). One set of data gives y = -30 +60x. The predicted volume for a tree of 18 INCHES is:

60 cubic feet

A survey of autos parked in student and staff lots at a large university were classified by country of origin, as seen in this table.Country of Origin DRIVER Student StaffAmerican 94 81European 38 22Asian 66 53What percent of the European car drivers were students?

63%

In order to plan the design of a school spirit shirt, the student council conducted a survey. They asked students which color they prefer (blue, white, maroon) and which type of shirt (t-shirt, sweatshirt). The table summarizes the responses. What percent of those who prefer maroon chose sweatshirt? https://files.catbox.moe/mrp4ay.PNG

66.7%

You are conducting an experiment to test the density of a new recipe for chocolate cake. You will test the recipe with 3 different baking temperatures (350, 400 and 450) and 3 different baking times (45 minutes, 55 minutes and 60 minutes). How many treatments are there?

9

It's easy to measure the circumference of a tree's trunk, but not so easy to measure its height. Foresters developed a model for ponderosa pines that they use to predict the tree's height (in feet) from the circumference of its trunk (in inches): height = 1.46 (circumference) + 5A lumberjack finds a tree with a circumference of 60 inches. How tall does this model estimate the tree to be? (Round to the nearest whole number)

93'

Given the least-squares regression line: [Cost of a Monopoly Property] = 67.3 + 6.78 * [Spaces From GO],FIND the residual for Reading Railroad which costs $200 and is 5 spaces from GO.

98.8

Listed below are names of the 20 pharmacists on the hospital staff. Use the random numbers below to select 4 pharamacists. Pastore:01, Back:02, Spiridonov:03, Ahi: 04, Hedge:05, MacDowell:06, Schissel:07, Novelli:08, Lavine:09, Kaplan:10, Highland:11, Roundy:12, Grubb:13, Markowitz:14, Glass:15, Davies:16, Golkowski:17, Reeves:18, Janis:19, Yen:20, Skip numbers 00 and 21-99.Skip any duplicate pharmacist selections. (A pharmacist cannot be selected more than once.) 04905 83852 29350 91397 19997 65142 05087 11232

Avi, Lavine, Grub and Janis

A large insurance company has 95 agents within a certain state. The histogram below shows the amount of insurance sold (in $100,000) for the period October through December in a recent year. The tallest bar, for example, indicates that 23 agents sold between $7.25 million and $7.75 million of insurance during a three-month period. Which of the following represents a box plot of the same data? https://files.catbox.moe/xm9u1d.PNG

C

In which one of the following distributions is the mean most likely greater than the median? https://files.catbox.moe/yuokjb.PNG

C

Which of the following represent a mosaic graph? https://files.catbox.moe/p5kbno.PNG

C

Listed below are names of the 20 pharmacists on the hospital staff. What are the possible ways to use a random number generator to select three of them to be in the sample? Pastore, Back, Spiridonov, Ahi, Hedge, MacDowell, Schissel, Novelli, Lavine, Kaplan, Highland, Roundy, Grubb, Markowitz, Glass, Davies, Golkowski, Reeves, Janis, Yen

Give each pharmacist a 2-digit number 00-19, Pastore:00, Back:01, Spiridonov:02, Ahi:03, Hedge:04, MacDowell:05,and so on in numerical order through the rest of the pharmacists ending with Yen:19 Look through random digits two at a time until 3 legitimate names are selected. Skip any numbers 20-99. Skip any duplicate selections for a pharmacist. (A pharmacist cannot be selected twice.) Give each pharmacist a 2-digit number 01-20, Pastore:01, Back:02, Spiridonov:03, Ahi:04, Hedge:05, MacDowell:06, and so on in numerical order through the rest of the pharmacists ending with Yen:20 Look through random digits two at a time until 3 legitimate names are selected. Skip any numbers 21-99 and 00. Skip any duplicate selections for a pharmacist. (A pharmacist cannot be selected twice.)

Which statement about influential points MUST be true? I. Removal of an influential point changes the slope of the regression line. II. Data points that are outliers in the horizontal direction are more likely to be influential than points that are outliers in the vertical direction. III. Influential points will always have large residuals.

I and II only

Consider the scatterplot of midterm and final exam scores for a class of 15 students. Which of the following are true statements? Read each statement and decide on its validity before selecting your answer. I. The same number of students scored 100 on the midterm exam as scored 100 on the final exam. II. Students who scored higher on the midterm exam tended to score higher on the final exam. III. The scatterplot shows a moderate negative correlation between midterm and final exam scores. https://files.catbox.moe/gjw5y2.PNG

I and III

We might choose to display data with a stemplot rather than a boxplot because a stemplot ... I. reveals the shape of the distribution II. is better for large data sets III. displays the actual data

I and III only

What is true of a data distribution having the BULK of the data at the lower numbers? I. The distribution is skewed to the right.II. The mean is smaller than the median.III. We should summarize with mean and standard deviation.

I only

Which of the following are true statements? READ THESE STATEMENTS VERY CAREFULLY and select all that are TRUE. I. Voluntary response samples often underrepresent people with strong opinions. II. Convenience samples often lead to undercoverage bias. III. Questionnaires with nonneutral wording are likely to have response bias.

II and III

A basketball player has a 70% free throw percentage. Which plan could be used to simulate the number of free throws that the player will likely make in the next five free throw attempts? Select all that apply. 1. Let 0,1 represent making the first shot, 2 and 3 represent making the second shot,....8 and 9 represent making the fifth shot. Generagte five random numbers 0-9, ignoring repeats. II. Let 0,1,2 represent missing a shot and 3,4,...9 represent making a shot. Generate five random numbers 0-9 and count how many numbers are in the range of 3-9. III. Let 0,1,2 represent missing a shot and 3,4,....9 represent making a shot. Generate five random numbers 0-9 and count how many numbers are in the range of 3-9, ignoring repeats.

II only

Mateo plays on his school basketball team. From past history, he knows that his probability of making a basket on a free throw is 0.7. Suppose he wants to create a simulation using random numbers to estimate the probability of making at least 3 baskets on his next 5 free throw attempts. Which of the following assignments of the digits 0 to 9 could be used for the simulation?

Let the digits from 0 to 6 represent making a basket and the digits from 7 to 9 represent not making a basket.

A factory has 20 assembly lines producing a popular toy. To inspect a representative sample of 100 toys, quality control staff randomly selected 5 toys from each line's output. Was this a SIMPLE RANDOM SAMPLE?

No, because not all combinations of 100 toys could have been chosen.

Is diet or exercise effective in combating insomnia? Some believe that cutting out desserts can help alleviate the problem, while others recommend exercise. Forty volunteers suffering from insomnia agreed to participate in a month-long experiment. Half were randomly assigned to a special no desserts diet while the others continued desserts as usual. Half of the people in each of these groups were randomly assigned to an exercise program and the others were told not to exercise. Those who ate no desserts and engaged in exercise showed the most improvement.Identify the population of interest.

People suffering from insomnia.

Bias can be controlled in surveys by all of the following except one. Choose the one option that will not control bias.

Prompting respondents so that they give correct responses.

The stemplot displays the 1988 per capita income (in hundreds of dollars) of the 50 states. Which of the following best describes the data? https://files.catbox.moe/gcyyl7.PNG

Skewed distribution, mean greater than median

A statistics student properly simulated the number of students at her high school who have the flu. She then reported, "The number of students at this school with the flu is 40."What is wrong with this conclusion?

The conclusion should indicate that the simulation suggests that there are 40 students at the school who have the flu. Actual results might not match the simulated results exactly.

A study was conducted on the weights of three different species of fish found in a lake in Finland. These three fish (bream, perch and roach) are commercial fish. Their weights are displayed in the boxplots above. Which of the following statements comparing these boxplots is NOT correct? https://files.catbox.moe/mn7pc2.PNG

The distributions of weights are approximately symmetric for all three species.

Use of the Internet worldwide increased steadily from 1990-2002. A scatterplot of this growth shows a strongly non-linear pattern. However, a scatterplot of ln Internet Users vs Year is much closer to linear. Below is a computer regression analysis of the transformed data (note that natural logarithms (ln above) are used). Which of the following best describe the model that is given by this computer printout? https://files.catbox.moe/9rf5cf.PNG

The exponential model: users(hat) = e^-951.10 (e^0.4785)year

A study of the fuel economy for various automobiles plotted the fuel consumption (in liters of gasoline used per 100 kilometers traveled) vs. speed (in kilometers per hour). A least-squares regression line was fitted to the data and the RESIDUAL PLOT is displayed to the right.What does the pattern of the residuals tell you about the linear model? https://files.catbox.moe/snl4mc.PNG

The residual plot clearly contradicts the linearity of the data.

As reported in the Journal of the American Medical Association (June 13, 1990), for a study of ten nonagenarians (90+yrs old), the following data shows a measure of strength versus a measure of functional mobility Strength (kg) 7.5 6 11.5 10.5 9.5 18 4 12 9 3 Walk time (s) 18 46 8 25 25 7 22 12 10 48 Find the LSRL and tell what the slope signifies?

The sign is negative, signifying that the greater the strength, the less the functional mobility.

Criticize the following simulation:A student assigns a random number from 1 to 13 to simulate the value of a card drawn at random from a standard deck of playing cards.

The simulation should model the real situation.

In 2001 a report in the Journal of the American Cancer Institute indicated that women who work nights have a 60% greater risk of developing breast cancer. Researchers based these finding on the work histories of 763 women with breast cancer and 741 women without the disease. True or False: This is a study and not an experiment

True

Company A has 500 employees and Company B has 750 employees. Union negotiators want to compare the salary distribution for the two companies. Which one of the following would be the most useful for accomplishing this comparison?

Two relative-frequency histograms for A and B drawn on the same scale

The Mars candy company starts a marketing campaign that puts a plastic game piece in each bag of M&Ms. 40% of the pieces show the letter "M," 10% show the symbol "&," and the rest just say "Try again." When you collect a set of three symbols "M," "&," and "M" you can turn them in for a free bag of candy. Suppose you want to estimate how many bags will a consumer have to buy to get a free one. Let's use a simulation to find out. 57821 76309 63508 29418 13026 34993 54636 17877 00987 23401 Which of the following ways could you conduct your simulation? (multiple selection possible)

Use 0-9 M: 0-3 &: 4 Try again: 5-9

The Mars candy company starts a marketing campaign that puts a plastic game piece in each bag of M&Ms. 25% of the pieces show the letter "M," 10% show the symbol "&," and the rest just say "Try again." When you collect a set of three symbols "M," "&," and "M" you can turn them in for a free bag of candy. Suppose you want to estimate how many bags will a consumer have to buy to get a free one. Let's use a simulation to find out. 57821 76309 63508 29418 13026 34993 54636 17877 00987 23401 Which of the following ways could you conduct your simulation? (multiple selection possible)

Use 00-99 M: 00-24 &: 25-34 Try again: 35-99

Vocabulary:Two variables that are actually not related to each other may nonetheless have a very high correlation because they both result from SOME OTHER, possibly HIDDEN, factor. This is an example of ...

a lurking variable.

A person with type O-positive blood can receive blood only from other type O donors. About 44% of the U.S. population has type O blood. At a blood drive, how many potential donors do you expect to examine in order to get three (3) units of type O blood?

between 6 and 10

Marketing researchers wonder if the color and type of a candy's packaging may influence sales of the candy. They manufacture test packages for chocolate mints in three colors (white, green, and silver) and three types (box, bag, and roll). Suspecting that sales may depend on a combination of package color and type, the researchers prepare nine different packages, then market them for several weeks in convenience stores in various locations. In this experiment ...What are the experimental units?

candy packages

A distribution shows the __________________ of a data set.

center, shape, and spread

We collect these data from 50 male students. Which variable is categorical?

eye color

A residual plot that indicates the model provides an appropriate description of the data ...

has no pattern

A member of the City Council has proposed a resolution opposing construction of a new state prison in his city. The council members decide they want to assess public opinion before they vote on this resolution. Below are some of the methods that are proposed to sample local residents to determine the level of public support for the resolution. Match each with one of the listed sampling techniques. You may have to arrive at one match by process of elimination.

https://files.catbox.moe/q7huak.PNG

The center of a histogram...

is the point in the graph where about half of the data lies above and half of the data lies below.

A company's sales grow by the SAME FIXED AMOUNT each year. That means the increase is the same year over year. This growth is ...

linear

Does regular exercise decrease the risk of cancer? A researcher finds 200 women over 50 who exercise regularly, pairs each with a woman who has a similar medical history but does not exercise, then follows the subjects for 10 years to see which group develops more cancer. This is a ..

prospective study

Does regular exercise decrease the risk of cancer? A researcher finds 200 women over 50 who exercise regularly, pairs each with a woman who has a similar medical history but does not exercise, then follows the subjects for 10 years to see which group develops more cancer. This is a ...

prospective study

Twenty dogs and twenty cats were subjects in an experiment to test the effectiveness of a new flea control chemical. It is suspected that cats and dogs may react differently to the new chemical and this is considered in the design of the experiment. Ten of the dogs and 10 of the cats were randomly assigned to an experimental group that wore a collar containing the chemical, while the others wore a similar collar without the chemical. After 30 days veterinarians were asked to inspect the animals for fleas and evidence of flea bites. This experiment is ..

randomized block, blocked by species

The table below shows how a company's employees commute to work. Transportation Car Bus TrainManagers 26 20 44Labor 56 106 168 What kind of display would be best to demonstrate an association, or not, between job classification and method of transportation?

side by side segmented bar graphs

Vocabulary:Residuals are ...

the difference between observed responses and values predicted by the model.

Environmental researchers have collected rain acidity data for SEVERAL DECADES. They want to see if there is any evidence that attempts to reduce industrial pollution have produced a TREND toward less acidic rainfall. They should display their data in a(n)

timeplot