1.In a survey people are asked "Which brand of toothpaste do you prefer?" The data gathered from this question would be what type of data?

A.categorical

B.quantitative

C.continuous

2.A student is gathering data on the driving experiences of other college students. One of the variables measured is the type of car the student drives. These data are coded using the following method: 1 = subcompact, 2 = compact, 3 = standard size, 4 = full size, 5 = premium, 6 = mini van, 7 = SUV, and 8 = truck.The student plans to see if there is a relationship between the number of speeding tickets a student gets in a year and the type of vehicle he or she drives. Identify the response variable in this study.

A.College students

B.type of car

C.number of speeding tickets

D.average number of speeding tickets last year

3.A researcher is studying the relationship between a vitamin supplement and cholesterol level. What type of study needs to be done in order to establish that the amount of vitamin supplement causes a change in cholesterol level?

A.Correlational study

B.Randomized experiment

C.Time Series study

D.Survey

4.Suppose two researchers wanted to determine if aspirin reduces the chance of a heart attack.Researcher 1 studied the medical records of 500 randomly selected patients. For each patient, he recorded whether the person took aspirin every day and if the person had ever had a heart attack. Then he reported the percentage of heart attacks for the patients who took aspirin every day and for those who did not take aspirin every day. What type of study did Researcher 1 conduct?

A.Observational

B.Experimental

C.Survey

D.None of the above

5.Suppose two researchers wanted to determine if aspirin reduces the chance of a heart attack.Researcher 2 also studied 500 patients that visited a regional hospital in the last year. He randomly assigned half (250) of the patients to take aspirin every day and the other half to take a placebo everyday. Then after a certain length of time he reported the percentage of heart attacks for the patients who took aspirin every day and for those who did not take aspirin every day. What type of study did Researcher 2 conduct?

A.Observational

B.Experimental

C.Survey

D.None of the above

6.The dean of a college would like to determine the feelings of students concerning a new registration fee that would be used to upgrade the recreational facilities on campus. All registered students would pay the fee each term. Which of the following data collection plans would provide the best representation of students' opinions at the school?

A.Survey every 10th student who enters the current recreational facilities between the hours of 1:00 and 5:00 pm until 100 students have been asked.

B.Randomly sample fifty student ID numbers and send a survey to all students in the sample.

C.Place an ad in the campus newspaper inviting students to complete an online survey. Collect the responses of the first 200 students who respond.

D.All of the above would be equally effective.

8.In order to determine which kind of data display (e.g., histogram versus bar graph) is appropriate for a given variable, one should consider which of the following:

A.whether the relevant variable is quantitative or categorical

B.whether the study is observational or experimental

C.the range of the data

9.A class survey asked students to indicate if they are MAC or PC users. Of the following graphs, which is most appropriate to display their results?

A.Pie chart

B.Histogram

C.Either a pie chart or a histogram

D.None of the above

19.The school committee of a small town wanted to determine the average number of children per household in their town. They divided the total number of children in the town by 50, the total number of households. Which of the following statements must be true if the average children per household is 2.2 children?

A.Half the households in the town have more than 2 children.

B.There are a total of 110 children in the town.

C.The most common number of children in a household is 2.2.

D.None of the above.

20.The distribution of the top 1% of individual incomes in the US is strongly skewed to the right. In 1997, the two measures of center for the top 1% of individual incomes were $330,000 and $675,000. Which number represents the mean income of the top 1% and which number represents the median income of the top 1%? Choose the best answer.

A.$330,000 is the mean and $675,000 is the median.

B.$330,000 is the median and $675,000 is the mean.

C.Not enough information to tell which is which.

22.You give a test to 100 students and determine the median score. After grading the test, you realize that the 10 students with the highest scores did exceptionally well. You decide to award these 10 students a bonus of 5 more points. The median of the new score distribution will be ___________ that of the original score distribution.

A.lower than

B.equal to

C.higher than

D.depending on skewness, higher or lower than

23.A college statistics class conducted a survey of how students spend their money. They gathered data from a large random sample of college students who estimated how much money they typically spent each week in different categories (e.g., food, entertainment, etc.). The following statistics were calculated for money spent weekly on food: mean = $31.52; median = $30.00; interquartile range = $34.00; standard deviation = $21.60; range = $132.50.A student states that the median food cost tells you that a majority of students in this sample spend about $30 each week on food. How do you respond?

A.Agree, the median is an average and that is what an average tells you.

B.Agree, $30 is representative of the data.

C.Disagree, a majority of students spend more than $30.

D.Disagree, the median tells you only that 50% of the sample spent less than $30 and 50% of the sample spent

24.A college statistics class conducted a survey of how students spend their money. They gathered data from a large random sample of college students who estimated how much money they typically spent each week in different categories (e.g., food, entertainment, etc.). The following statistics were calculated for money spent weekly on food: mean = $31.52; median = $30.00; interquartile range = $34.00; standard deviation = $21.60; range = $132.50.The class determined that a mistake had been made and a value entered as 138 should have been entered as 38. They recalculate all of the statistics. Which of the following would be true?

A.The value of the median decreases, the value of the mean stays the same.

B.The values of the median and mean both decrease.

C.The value of the median stays the same, the value of the mean decreases.

25.A class of 30 introductory statistics students took a 15 item quiz, with each item worth 1 point. The standard deviation for the resulting score distribution is 0. You know that:

A.about half of the scores were above the mean.

B.an arithmetic error must have been made.

C.everyone correctly answered the same number of items.

D.the mean, median, and mode must all be 0.

26.The 30 introductory statistics students took another quiz worth 30 points. On this quiz, the standard deviation of the scores of that quiz was 1 point. Which of the following gives the most suitable interpretation?

A.all of the individual scores are one point apart

B.the difference between the highest and lowest score is 1

C.the difference between the upper and lower quartile is 1

D.a typical score is within 1 point of the mean

29.A teacher gives a 15 item science test. For each item, a student receives one point for a correct answer; 0 points for no answer; and loses one point for an incorrect answer. Total test scores could range from +15 points to -15 points. The teacher computes the standard deviation of the test scores for the class to be -2.30. What do we know?

A.The standard deviation was calculated incorrectly.

B.Most students received negative scores.

C.Most students scored below the mean.

D.None of the above.

33.A random sample was taken to determine the left foot length of female bears based on measuring their tracks. The following statistics were calculated for this sample: Mean = 12.8 inches, median = 12.7 inches, standard deviation = 1.4 inches, interquartile range = 2 inches. The distribution is mound-shaped and symmetric. Based only on this information, choose the best estimates for the minimum and maximum values of the distribution.

A.min = 11.4 and max = 14.2

B.min = 10.7 and max = 14.7

C.min = 8.6 and max = 17.0

36.Sam is interested in bird nest construction, and finds a correlation of .82 between the depth of a bird nest (in inches) and the width of the bird nest (in inches) at its widest point. Sue, a classmate of Sam, is also interested in looking at bird nest construction, and measures the same variables on the same bird nests that Sam does, except she does her measurements in centimeters, instead of inches. What should her correlation be?

A.Sue's correlation should be 1, because it will match Sam's exactly.

B.Sue's correlation would be 1.64(.82) = 1.3448, because you need to change the units from inches to centimeters and 1 inch = 1.64 centimeters.

C.Sue's correlation would be .82, the same as Sam's.

37.The correlation between height and weight for a certain breed of plant is found to be .75. What percentage of the variability in plant weight is NOT explained by height?

A.1-.75 = .25 or 25%

B.(.75)^2 = .5625 or 56.25%

C.1-(.75)^2 = .4375 or 43.75%

D.(1-.75)^2 = .0625 or 6.25%

38.A student was studying the relationship between how much money students spend on food and on entertainment per week. Based on a sample size of 270, he calculated a correlation coefficient (r) of .013 for these two variables. Which of the following is an appropriate interpretation?

A.This low correlation of .013 indicates there is no relationship.

B.There is no linear relationship but there may be a nonlinear relationship.

C.This correlation indicates there is some type of linear relationship.

44.A random sample of 25 Real Estate listings for houses in the Northeast section of a large city was selected from the city newspaper. A correlation coefficient of -.80 was found between the age of a house and its list price. Which of the following statements is the best interpretation of this correlation?

A.Older houses tend to cost more money than newer houses.

B.Newer houses tend to cost more money than older houses.

C.Older houses are worth more because they were built with higher quality materials and labor.

D.New houses cost more because supplies and labor are more expensive today.

47.A statistics student gathered data on a large numbers of cars of a particular model, from new cars to those that were up to 10 years old. Using the data on car ages (in years) and car prices (in US dollars) he found a linear relationship and produced the following regression model:

Predicted Price = 15620 - 1440 * Age

A friend asked him to predict the price of a 5 year old model of this car, using his equation. Which of the following is the most correct response to provide?

A.Plot a regression line, find 5 on the horizontal axis, and read off the corresponding value on the y axis.

B.Substitute 5 in the equation and solve for "price".

C.Both of these methods are correct.

D.Neither of these methods is correct.

48.A statistics student gathered data on a large numbers of cars of a particular model, from new cars to those that were up to 10 years old. Using the data on car ages (in years) and car prices (in US dollars) he found a linear relationship and produced the following regression model:

Predicted Price = 15620 - 1440 * Age

What is the best interpretation of the slope?

A.As the car ages by one year, the price increases by $5620.

B.As the car ages by one year, the price decreases by $5620.

C.As the car ages by one year, the price increases by $1440.

D.As the car ages by one year, the price decreases by $1440.

49.A statistics student gathered data on a large numbers of cars of a particular model, from new cars to those that were up to 10 years old. Using the data on car ages (in years) and car prices (in US dollars) he found a exponential relationship and produced the following regression model:

Predicted Price = 15000(0.91)^Age

Which of the following is the annual percent decrease?

A.9%

B.91%

C..91^2 = .8281

D.15000

50.A statistics instructor wants to use the number of hours studied to predict exam scores in his class. He wants to use a linear regression model. Data from previous years shows that the average number of hours studying for a final exam in statistics is 8.5, with a standard deviation of 1.5, and the average exam score is 75, with a standard deviation of 15. The correlation is .76. Should the instructor use linear regression to predict exam scores for a student who studied 10 hours for the final?

A.Yes, there is a high correlation, so it is alright to use linear regression.

B.Yes, because linear regression is the statistical method used to make predictions when you have bivariate quantitative data.

C.Linear regression could be appropriate if the scatterplot shows a clear linear relationship.

D.No, because there is no way to prove that more hours of study causes higher exam scores.