1. A researcher wanted to determine whether eating sugary cereal for breakfast increased the aggression of second graders during their morning play period. After feeding a group of 20 students sugary cereal for breakfast she observed that, on average, the students committed 4.5 aggressive behaviors during their morning play period. In this example, the descriptive statistic is:

2. Wendy is a weight-loss group leader. To get a better idea of how to help those she will be working with to achieve their weight-loss goals, she wishes to know the average weight-loss goal of the individuals in her group. What kind of statistic should Wendy use?

3. A community researcher wanted to explore the connection between the number of bathrooms in a house and the sale price of the house. She studied 1750 home sales in an economically diverse, medium-sized city, and she found that the average sale price went up by $63,000 for each full bath. What is the descriptive statistic in this study?

4. A descriptive statistic is generally defined as:

5. A medical researcher interested in asthma symptoms wanted to know how symptoms were affected in dry versus humid conditions. The researchers recruited 18 asthma patients to spend four weeks under two conditions: sleeping with a dehumidifier for two weeks to create a "dry" environment and sleeping with a humidifier for the remaining two weeks to create a "humid" environment. Patients were asked to rate their symptoms at regular intervals using a scale from "0 – no symptoms" to "20 – maximum asthma symptoms." The change in asthma symptoms from dry to humid conditions was 5.82, showing a reduction of symptoms in humid conditions. What was the descriptive statistic in this study?

6. A researcher wanted to determine whether eating sugary cereal for breakfast increased the aggression of second graders during their morning play period. After feeding a group of 20 students sugary cereal for breakfast she observed that, on average, the students committed 4.5 aggressive behaviors during their morning play period. In this example, the sample is:

7. Hsee and Tang (2007) reported the results of a study in which 195 college students completed a happiness scale (from 1 to 7) just before taking a midterm exam. On this scale, 1 corresponded to very unhappy and 7 to very happy. On average, the students rated their happiness as 6.18. In this study, which of these would require an inferential statistic?

8. Inferential statistics allow a researcher to:

9. Unnithan, Houser, and Fernhall (2006) were interested in whether playing the game Dance Dance Revolution (DDR) met the American College of Sports Medicine recommendations for exercise to improve cardiovascular health. Twenty-two adolescents, 10 of whom were classified as overweight and 12 of whom were not overweight, played DDR for 12 minutes. During the 12 minutes, the researchers measured each participant's heart rate. On average, the researchers found no difference between the heart rates of the two groups. Both groups' heart rates were above the minimum recommended for cardiovascular exercise. What is the sample in this study?

10. Unnithan, Houser, and Fernhall (2006) were interested in whether playing the game Dance Dance Revolution (DDR) met the American College of Sports Medicine recommendations for exercise to improve cardiovascular health. Twenty-two adolescents, 10 of whom were classified as overweight and 12 of whom were not overweight, played DDR for 12 minutes. During the 12 minutes, the researchers measured each participant's heart rate. On average, the researchers found no difference between the heart rates of the two groups. Both groups' heart rates were above the minimum recommended for cardiovascular exercise. Which of these requires an inferential statistic?

11. A researcher wanted to determine whether eating sugary cereal for breakfast increased the aggression of second graders during their morning play period. After feeding a group of 20 students sugary cereal for breakfast she observed that, on average, the students committed 4.5 aggressive behaviors during their morning play period. In this example, the population is:

12. Unnithan, Houser, and Fernhall (2006) were interested in whether playing the game Dance Dance Revolution (DDR) met the American College of Sports Medicine recommendations for exercise to improve cardiovascular health. Twenty-two adolescents, 10 of whom were classified as overweight and 12 of whom were not overweight, played DDR for 12 minutes. During the 12 minutes, the researchers measured each participant's heart rate. On average, the researchers found no difference between the heart rates of the two groups. Both groups' heart rates were above the minimum recommended for cardiovascular exercise. What is the population in this study?

13. Why do researchers typically study samples rather than populations?

14. The statement "100 college-aged students participated in a study examining the relationship between gender and depression" is an example of a(n) _____ in research and statistics.

15. A community researcher wanted to explore the connection between the number of bathrooms in a house and the sale price of the house. When he studied 1750 home sales in an economically diverse, medium-sized city, he found that the average sale price went up by $63,000 for each full bath. What is the sample in this study?

16. A community researcher wanted to explore the connection between the number of bathrooms in a house and the sale price of the house. He studied 1750 home sales in an economically diverse, medium-sized city, and he found that the average sale price went up by $63,000 for each full bath. Which statement involves a logical inferential statistic based on this research?

17. A community researcher wanted to explore the connection between the number of bathrooms in a house and the sale price of the house. She studied 1750 home sales in an economically diverse, medium-sized city, and she found that the average sale price went up by $63,000 for each full bath. What is a logical population to which the researcher would want to extend this finding?

18. A sample is generally defined as:

19. A population is generally defined as:

20. An inferential statistic is generally defined as:

21. A medical researcher interested in asthma symptoms wanted to know how symptoms were affected in dry versus humid conditions. The researchers recruited 18 asthma patients to spend four weeks under two conditions: sleeping with a dehumidifier for two weeks to create a "dry" environment and sleeping with a humidifier for the remaining two weeks to create a "humid" environment. Patients were asked to rate their symptoms at regular intervals using a scale from "0 – no symptoms" to "20 – maximum asthma symptoms." The change in asthma symptoms from dry to humid conditions was 5.82, showing a reduction of symptoms in humid conditions. What was the sample in this study?

22. A medical researcher interested in asthma symptoms wanted to know how symptoms were affected in dry versus humid conditions. The researchers recruited 18 asthma patients to spend four weeks under two conditions: sleeping with a dehumidifier for two weeks to create a "dry" environment and sleeping with a humidifier for the remaining two weeks to create a "humid" environment. Patients were asked to rate their symptoms at regular intervals using a scale from "0 – no symptoms" to "20 – maximum asthma symptoms." The change in asthma symptoms from dry to humid conditions was 5.82, showing a reduction of symptoms in humid conditions. What is MOST likely the population of interest for this researcher?

23. A medical researcher interested in asthma symptoms wanted to know how symptoms were affected in dry versus humid conditions. The researchers recruited 18 asthma patients to spend four weeks under two conditions: sleeping with a dehumidifier for two weeks to create a "dry" environment and sleeping with a humidifier for the remaining two weeks to create a "humid" environment. Patients were asked to rate their symptoms at regular intervals using a scale from "0 – no symptoms" to "20 – maximum asthma symptoms." The change in asthma symptoms from dry to humid conditions was 5.82, showing a reduction of symptoms in humid conditions. Which statement involves an inferential statistic related to this research finding?

24. An elementary school teacher is interested in the relation between sugar consumption and activity level in preschool children. The teacher gives 30 preschool children from Preppy Preschool Playland 0 milligrams, 20 milligrams, or 50 milligrams of sucrose (sugar) in a breakfast drink. She then observes their behavior for 30 minutes during their morning outdoor play period and codes their activity level. In this example, the population is:

25. An elementary school teacher is interested in the relation between sugar consumption and activity level in preschool children. The teacher gives 30 preschool children from Preppy Preschool Playland 0 milligrams, 20 milligrams, or 50 milligrams of sucrose (sugar) in a breakfast drink. She then observes their behavior for 30 minutes during their morning outdoor play period and codes their activity level. In this example, the sample is:

26. Variables are:

27. A variable that consists of separate specific categories for which there are no values between categories is:

28. Which of these is NOT a variable?

29. A variable for which there is an infinite number of values between any two points on the scale is:

30. Which variables are always discrete?

31. Emily is a student at a large university. When visiting professors during their office hours, she has noticed that many have refrigerators in their offices. She decides to survey 80 faculty and count the total number of refrigerators they have. What is the variable in this study?

32. Emily is a student at a large university. When visiting professors during their office hours, she has noticed that many have refrigerators in their offices. She decides to survey 80 professors and count the total number of refrigerators they have. What type of observation is she making?

33. When you read your college textbooks, you may sometimes find errors in them. If you track the number of errors based on the edition of the textbook, you might find that 1st editions have more errors than 3rd, 5th, and 10th editions. What type of variable is the edition of the text you are assessing?

34. A five-star rating system for movies is a(n) _____ variable.

35. A person's political affiliation is a(n) _____ variable.

36. The United States Department of Homeland Security Threat Advisory System measures threat as severe, high, elevated, guarded, or low. In this system, threat is:

37. Eye color—assessed as blue, green, hazel, brown, and other—as a variable is measured on a(n) _____ scale.

38. In a student election, five people run for student body president. The votes are tallied to create a list of candidates from most to least popular. The number of votes is then removed so that the candidates are only presented from most to least popular. Popularity is a(n) _____ variable.

39. The number of times a person eats fast food each week is:

40. A person's grade point average on a scale from 0 to 4.0 is a(n) _____ variable.

41. The amount of food a person eats each week (as measured in ounces) is:

42. The measurement of the performance of runners in a race based on their finishing places is a(n) _____ variable. The measurement of the performance of runners in a race based on their times to complete the race is a(n) _____ variable.

43. In a student election, five people run for student body president. The votes are tallied to create a list of candidates from most to least popular. When the number of votes are actually presented, this is a(n) _____ variable.

44. Imagine that a variable "sensitivity to others" is measured from 0 (low) to 10 (high). Although it is possible to have low sensitivity to others, it is not conceptually possible to have no sensitivity at all. What type of variable is this MOST likely to be?

45. The number of aces served in tennis matches is calculated for 50 elite tennis players. What type of variable is number of aces?

46. The difference between an interval and a ratio variable is that:

47. Which types of variables are considered scale variables by statistical computing packages such as SPSS?

48. _____ variables are almost always continuous.

49. In 2010, there was an interesting lawsuit about bagels. A company claimed to have created a new way to re-create "Brooklyn-style" bagels and then reported that another bagel producer stole its recipe. A researcher wonders if bagel sales might have been affected simply by the story making the national news, so she tracks total bagel sales in dollars for one year before and after the news story hits. What type of variable is total bagel sales?

50. When you read your college textbooks, you may sometimes find errors in them. If you track the number of errors based on the edition of the textbook, you might find that 1st editions have more errors than 3rd, 5th, and 10th editions. What type of variable is the number of errors found?

51. A New York Times article published on April 24, 2007, reported the research of Dr. Giorgio Vallortigara, a neuroscientist at the University of Trieste, Italy. In this study, Dr. Vallortigara assessed whether a dog's tail wags in a preferred direction in response to positive as opposed to negative stimuli. First, Dr. Vallortigara recruited 30 dogs that were family pets. While filming a dog's tail from above, he allowed the dog to view (through a slot in its cage) its owner, an unfamiliar human, a cat, and an unfamiliar dominant dog. The study found that dogs' tails wagged to the right for the owner and to the left for the unfamiliar dominant dog. What type of measure was the independent variable in this study?

52. A New York Times article published on April 24, 2007, reported the research of Dr. Giorgio Vallortigara, a neuroscientist at the University of Trieste, Italy. In this study, Dr. Vallortigara assessed whether a dog's tail wags in a preferred direction in response to positive as opposed to negative stimuli. First, Dr. Vallortigara recruited 30 dogs that were family pets. While filming a dog's tail from above, he allowed the dog to view (through a slot in its cage) its owner, an unfamiliar human, a cat, and an unfamiliar dominant dog. The study found that dogs' tails wagged to the right for the owner and to the left for the unfamiliar dominant dog. What type of measure was the dependent variable in this study?

53. The term level refers to the:

54. The variable that is manipulated or observed in order to determine its effects on another variable is the _____ variable.

55. A researcher was interested in the effects of gender on attitudes toward women in leadership positions. The researcher surveyed a group of individuals, 12 of whom were men and 12 of whom were women. In this example, men is a(n) _____ variable.

56. A researcher was interested in the effects of gender on attitudes toward women in leadership positions. The researcher surveyed a group of individuals, 12 of whom were men and 12 of whom were women. In this example, gender would be considered the _____ variable.

57. A New York Times article published on April 24, 2007, reported the research of Dr. Giorgio Vallortigara, a neuroscientist at the University of Trieste, Italy. In this study, Dr. Vallortigara assessed whether a dog's tail wags in a preferred direction in response to positive as opposed to negative stimuli. First Dr. Vallortigara recruited 30 dogs that were family pets. While filming a dog's tail from above, he allowed the dog to view (through a slot in its cage) its owner, an unfamiliar human, a cat, and an unfamiliar dominant dog. The study found that dogs' tails wagged to the right for the owner and to the left for the unfamiliar dominant dog. What is the independent variable in this study?

58. The outcome variable that we would expect to change with changes in the independent variable is the _____ variable.

59. A researcher was interested in the effects of gender on attitudes toward women in leadership positions. The researcher surveyed a group of individuals, 12 of whom were men and 12 of whom were women. In this example, what would be the dependent variable?

60. Dr. Feldman was interested in the effect of Valium on motor performance. He had his student research assistants inject 30 rats in the experimental group with a small amount of Valium, and 30 rats in the control group with saline solution. Following the injections, the rate of bar pressing by both groups of rats was measured. On average, rats in the control group had 800 presses per hour and rats in the experimental group had 715 presses per hour. The same testing box was used for both groups of rats, but one student assistant tested the control and a second student assistant tested the experimental group. In this example, having two different student assistants test the two groups is a(n) _____ variable.

61. A New York Times article published on April 24, 2007, reported the research of Dr. Giorgio Vallortigara, a neuroscientist at the University of Trieste, Italy. In this study, Dr. Vallortigara assessed whether a dog's tail wags in a preferred direction in response to positive as opposed to negative stimuli. First Dr. Vallortigara recruited 30 dogs that were family pets. While filming a dog's tail from above he allowed the dog to view (through a slot in its cage) its owner, an unfamiliar human, a cat, and an unfamiliar dominant dog. The study found that dogs' tails wagged to the right for the owner and to the left for the unfamiliar dominant dog. What is the dependent variable in this study?

62. A researcher studies length of time in college, first through fourth year, and its relation to academic motivation. To get the most detail out of her measures, she assesses each student in both the fall and spring semesters of each of their four years in school. She finds that students have increasingly higher motivation from their first semester to their seventh semester (the start of their fourth year), with a trailing off in the last semester. What is the independent variable in this study?

63. A researcher studies year in college, first through fourth year, and its relation to academic motivation. To get the most detail out of her measures, she assesses each student in both the fall and spring semesters of each their four years in school. She finds that students have increasingly higher motivation from their first to fourth year, with a trailing off in the last semester. What is the dependent variable in this study?

64. In a variant of the Coke/Pepsi Challenge, tasters try to identify regular and diet versions of these popular beverages under "blind" conditions, in which they can't see the two products. How many levels are there to the independent variable?

65. In 2010, there was an interesting lawsuit about bagels. A company claimed to have created a new way to re-create "Brooklyn-style" bagels and then reported that another bagel producer had stolen its recipe. A researcher wonders if bagel sales might have been affected simply by the fact of the story making the national news, so she tracks total bagel sales in dollars for one year before and after the news story hits. What is the independent variable in this study?

66. In 2010, there was an interesting lawsuit about bagels. A company claimed to have created a new way to re-create "Brooklyn-style" bagels and then reported that another bagel producer had stolen its recipe. A researcher wonders if bagel sales might have been affected simply by the fact of the story making the national news, so she tracks total bagel sales in dollars for one year before and after the news story hits. What is the dependent variable in this study?

67. A weight-management researcher was interested in whether the size of a person's breakfast could deter overall food consumption throughout the rest of the day. He creates two breakfast groups, a 350-calorie breakfast and a 750-calorie breakfast; assigns six participants to each group; and tracks the total calories participants eat in one day. Because of the detailed attention needed to accurately interview participants about their eating, he works with the high-calorie group and has his assistant interview the low-calorie group. What is the independent variable in this study?

68. A weight-management researcher was interested in whether the size of a person's breakfast could deter overall food consumption throughout the rest of the day. He creates two breakfast groups, a 350-calorie breakfast and a 750-calorie breakfast; assigns six participants to each group; and tracks the total calories participants eat in one day. Because of the detailed attention needed to accurately interview participants about their eating, he works with the high-calorie group and has his assistant interview the low-calorie group. What is the dependent variable in this study?

69. A weight-management researcher was interested in whether the size of a person's breakfast could deter overall food consumption throughout the rest of the day. He creates two breakfast groups, a 350-calorie breakfast and a 750-calorie breakfast; assigns six participants to each group; and tracks the total calories participants eat in one day. Because of the detailed attention needed to accurately interview participants about their eating, he works with the high-calorie group and has his assistant interview the low-calorie group. What is the confounding variable in this study?

70. A weight-management researcher was interested in whether the size of a person's breakfast could deter overall food consumption throughout the rest of the day. He creates two breakfast groups, a 350-calorie breakfast and a 750-calorie breakfast; assigns six participants to each group; and tracks the total calories participants eat in one day. Because of the detailed attention needed to accurately interview participants about their eating, he works with the high-calorie group and has his assistant interview the low-calorie group. How many levels does the independent variable have in this study?

71. An elementary school teacher is interested in the relation between sugar consumption and activity level in preschool children. The teacher gives 30 preschool children from Preppy Preschool Playland 0 milligrams, 20 milligrams, or 50 milligrams of sucrose (sugar) in a breakfast drink. She then observes their behavior for 30 minutes during their morning outdoor play period and codes their activity level. In this example, the independent variable is:

72. An elementary school teacher is interested in the relation between sugar consumption and activity level in preschool children. The teacher gives 30 preschool children from Preppy Preschool Playland 0 milligrams, 20 milligrams, or 50 milligrams of sucrose (sugar) in a breakfast drink. She then observes their behavior for 30 minutes during their morning outdoor play period and codes their activity level. In this example, the dependent variable is:

73. Professor Martin wanted to find out which of two popular statistics textbooks (Statistics: It Will Change Your Life and Statistics: Bigger, Better, Stronger) would be a better book for students. To help her decide, she compared the two texts by assigning one textbook to a section of statistics taught by Professor Miller from 10 to 11 A.M. on Monday, Wednesday, and Friday, and the other text to a section of statistics taught by Professor Mervin from 7 to 10 P.M. on Wednesday evenings. At the end of the term, all students took the same comprehensive test. Students to whom Statistics: Bigger, Better, Stronger was assigned performed better on the test than did students to whom Statistics: It Will Change Your Life was assigned. Professor Martin therefore concluded that the former textbook was the better one. What was the independent variable in this study?

74. Professor Martin wanted to find out which of two popular statistics textbooks (Statistics: It Will Change Your Life and Statistics: Bigger, Better, Stronger) would be a better book for students. To help her decide, she compared the two texts by assigning one textbook to a section of statistics taught by Professor Miller from 10 to 11 A.M. on Monday, Wednesday, and Friday, and the other text to a section of statistics taught by Professor Mervin from 7 to 10 P.M. on Wednesday evenings. At the end of the term, all students took the same comprehensive test. Students to whom Statistics: Bigger, Better, Stronger was assigned performed better on the test than did students to whom Statistics: It Will Change Your Life was assigned. Professor Martin therefore concluded that the former textbook was the better one. What was the dependent variable in this study?

75. Professor Martin wanted to find out which of two popular statistics textbooks (Statistics: It Will Change Your Life and Statistics: Bigger, Better, Stronger) would be a better book for students. To help her decide, she compared the two texts by assigning one textbook to a section of statistics taught by Professor Miller from 10 to 11 A.M. on Monday, Wednesday, and Friday, and the other text to a section of statistics taught by Professor Mervin from 7 to 10 P.M. on Wednesday evenings. At the end of the term, all students took the same comprehensive test. Students to whom Statistics: Bigger, Better, Stronger was assigned performed better on the test than did students to whom Statistics: It Will Change Your Life was assigned. Professor Martin therefore concluded that the former textbook was the better one. Which of the following is NOT a potential confounding variable in this study?

76. When a test measures what it is intended to measure, the test is said to be:

77. Jonathon has taken the GRE three times. Every time he takes it he gets a 500 on the math section. This implies that:

78. The Beck Depression Inventory (BDI) is a scale intended to measure depression levels, with higher scores indicating higher levels of depression. If the BDI is a valid measure of depression, we would expect that:

79. The Consideration of Future Consequences scale is intended to measure the extent to which an individual considers the future when making immediate choices. If the scale is a reliable measure, we would expect that:

80. People debate whether standardized tests, such as the ACT and SAT, are predictors of college performance. This is essentially a debate about:

81. Clayton has a history of depression. As part of his self-care, he takes a depression assessment every six months. His results tend to be very consistent, except when he is in a serious depression and his results show elevated levels of depression. The tendency for his results to be consistent supports the _____ of the assessment.

82. Clayton has a history of depression. As part of his self-care, he takes a depression assessment every six months. His results tend to be very consistent, except when he is in a serious depression and his results show elevated levels of depression. The fact that Clayton's results vary with his changes in mood, mirroring his depression levels, supports the _____ of the assessment.

83. Hypothesis testing refers to:

84. In an experiment designed to assess the effects of disclosure of ingredients on the experience of taste, Lee, Frederick, and Ariely (2006) approached patrons at a local pub and asked them to taste and rate a new beer: the MIT Brew. Some participants were told about the secret ingredient in the beer (a few drops of balsamic vinegar) either before tasting (before condition) or after tasting but before rating (after condition). Other participants were not told anything regarding the secret ingredient (not told condition). Which aspect of this study is an operational definition of the dependent variable?

85. An operational definition is one that:

86. In 2000, Bartels and Zeki performed a study in which they hypothesized that there may be special pathways in the brain that support the feeling of romantic love. To test their hypothesis they recruited volunteers who reported themselves to be "truly, deeply, and madly in love." They then used brain imaging methods to determine which areas of the volunteers' brains were active when looking at pictures of their loved one. How did these researchers operationally define romantic love?

87. A correlation measures the relationship between _____ or more variables.

88. Controlling for _____ variables permits researchers to make statements about cause–effect relationships between variables.

89. A researcher is interested in the effectiveness of natural remedies for allergies. The researcher randomly assigns 3 different treatments to 30 allergy sufferers: a treatment of herbal tea, homeopathic doses of the allergens, or a traditional antihistamine. What type of research design has the researcher employed?

90. Random assignment refers to a situation in which:

91. The purpose of random assignment to groups is to:

92. What research technique is crucial to drawing the conclusion that the independent variable caused the change in the dependent variable?

93. Why does random assignment help control for confounding variables?

94. A New York Times article published on April 24, 2007, reported the research of Dr. Giorgio Vallortigara, a neuroscientist at the University of Trieste, Italy. In this study, Dr. Vallortigara assessed whether a dog's tail wags in a preferred direction in response to positive as opposed to negative stimuli. First Dr. Vallortigara recruited 30 dogs that were family pets. While filming a dog's tail from above, he allowed the dog to view (through a slot in its cage) its owner, an unfamiliar human, a cat, and an unfamiliar dominant dog. The study found that dogs' tails wagged to the right for the owner and to the left for the unfamiliar dominant dog. What type of research design did Dr. Vallortigara employ?

95. A researcher wants to assess well-being among dog and cat owners. She administers a well-being assessment to 125 dog owners and 163 cat owners. What type of research design is being used?

96. Reading times are collected for bilingual participants, comparing their reading speed across their two languages. What type of research design would MOST likely be used in this study?

97. Often, a researcher cannot conduct an experiment because it is:

98. Professor Harvey wants to investigate the relationship between the number of cigarettes smoked per day and overall respiratory health. Why can't Professor Harvey conduct an experiment comparing the respiratory health of people smoking 0, 20, and 40 cigarettes a day?

99. In correlational research:

100. Möller and Krahé (2009) studied German teenagers over a period of 30 months. They found that the amount of video game playing engaged in when the study started was related to aggression 30 months later. Which of the following best summarizes these findings?

101. A researcher wants to design an experiment to study the effects of parental neglect. Why can't this researcher randomly recruit parents to participate in this experiment?