Psych 100a Quiz 1

A national survey of smoking behavior classifies respondents as non-smokers, non-daily smokers, and daily smokers. What is the level of measurement for this variable?

a. Nominal

b. Continuous

c. Ordinal

c. Ordinal

A study examining the use of and engagement with Facebook asked participants to report the number of friends. Respondents chose between nine options of custom ranges, e.g., "10 or less", "11-50", "51-100", etc. Which level of measurement describes this variable?

a. Nominal

b. Ordinal

c. Continuous

b. Ordinal

A popular depression scale classifies people into the following groups: no depression, mild depression, and clinical depression. Which level of measurement describes the depression variable?

a. Ordinal

b. Nominal

c. Continuous

a. Ordinal

Which of the following variables is measured on a continuous scale?

a. Treatment assignment (treatment vs. control)

b. Number of children in a family

c. Self-reported health (poor, fair, good, excellent)

d. Political affiliation

b. Number of children in a family

A study of post-partum depression found that most mothers reported moderate levels of depression, and very low and very high depression scores were relatively rare. What distribution shape best describes this variable?

a. Positively skewed

b. Negatively skewed

c. Uniform

d. Normal

d. Normal

A distribution of midterm exam scores has a strong negative skew. Which of the following is true?

a. Few people have very high scores

b. Few people have very low scores

c. Most scores are moderate, somewhere in the middle

d. Most scores are very low

b. Few people have very low scores

A depression questionnaire asks the following three items, each of which is measured on a 1 (Strongly disagree) to 5 (Strongly agree) scale.

I felt that I had nothing to look forward to

I felt down-hearted and blue.

I felt that life was meaningless

A researcher forms a scale score by summing responses to the three items. What is the maximum value for the scale score?

15

A study indicates that antioxidants found in blueberries may slow down the process of aging. In an animal study, 19-month-old rats (equivalent to 60-year-old humans) were fed either their standard diet or a diet supplemented by either blueberry, strawberry, or spinach powder. After eight weeks, the rats were given memory and motor skills tests. Although all supplemented rats showed improvement, those supplemented with blueberry powder showed the most notable improvement. What role does the diet variable (standard, blueberry, strawberry, spinach powder) play in this study?

a. Outcome (dependent) variable

b. Explanatory (independent) variable

c. Control variable (covariate)

d. Confounding variable

b. Explanatory (independent) variable

Which of the following variables is measured on an ordinal scale?

a. Treatment assignment (treatment vs. control)

b. Political affiliation

c. Number of children in a family

d. Self-reported health (poor, fair, good, excellent)

d. Self-reported health (poor, fair, good, excellent)

A study examining the use of and engagement with Facebook asked participants about weekly minutes spent logged on. Which level of measurement describes this variable?

a. Nominal

b. Ordinal

c. Continuous

c. Continuous

Which of the following variables is measured on a nominal scale?

a. Ethnicity

b. Education level( less than HS, HS grad, some college, college grad)

c. Income (<30K, 30K-50K, 50K-80K, 80K or higher)

d. IQ

a. Ethnicity

A study of post-partum depression includes a questionnaire item asking mothers to report the number of children in the family. Most mothers reported having only one child, and the number of mothers reporting 2, 3, and 4 children steadily decreased. What distribution shape best describes this variable?

a. Negatively skewed

b. Uniform

c. Normal

d. Positively skewed

d. Positively skewed

A study of post-partum depression found a relatively even number of mothers with low, moderate, and high depression levels. What distribution shape best describes the depression variable?

a. Positively skewed

b. Normal

c. Uniform

d. Negatively skewed

c. Uniform

A depression questionnaire asks the following three items, each of which is measured on a 1 (Strongly disagree) to 5 (Strongly agree) scale.

I felt that I had nothing to look forward to

I felt down-hearted and blue.

I felt that life was meaningless.

A researcher forms a scale score by summing responses to the three items. What is the minimum value for the scale score?

3

A national survey of smoking behavior asks respondents to report their family's total household income to the nearest dollar. What is the level of measurement for the income variable?

Select one:

a. Nominal

b. Ordinal

c. Continuous

c. Continuous

A computer-administered measure of prejudice presents participants with a statement about a particular ethic group and then records the amount of time it takes participants to respond to the prompt. What is the level of measurement for the reaction time variable?

Select one:

a. Continuous

b. Nominal

c. Ordinal

a. Continuous

A depression questionnaire asks the question, "I felt that I had nothing to look forward to." Respondents answered on a scale ranging from 1 (Strongly disagree) to 5 (Strongly agree). Which level of measurement describes this variable?

Select one:

a. Ordinal

b. Nominal

c. Continuous

a. Ordinal

Beta-carotene supplements have been thought to protect against cancer. A study published in the Journal of the National Cancer Institute randomly assigned women to receive a beta-carotene supplement or a placebo, and years later researchers recorded whether the women developed cancer. What role does the beta-carotene supplement vs. placebo distinction play in this study?

Select one:

a. Outcome (dependent) variable

b. Explanatory (independent) variable

c. Confounding variable

d. Control variable (covariate)

b. Explanatory (independent) variable

A national survey of smoking behavior classifies respondents into four ethnic groups: white non-Hispanic, black non-Hispanic, Hispanic, and other non-Hispanic. What is the level of measurement for this variable?

Select one:

a. Ordinal

b. Continuous

c. Nominal

c. Nominal

Which of the following variables is measured on a continuous scale?

Select one:

a. Income (< 30K, 30K-50K, 50K-80K, 80K or higher)

b. IQ

c. Treatment assignment (treatment vs. control)

d. Education level (less than HS, HS grad, some college, college grad)

b. IQ

A depression questionnaire asks the following three items, each of which is measured on a 1 (Strongly disagree) to 5 (Strongly agree) scale.

I felt that I had nothing to look forward to

I felt down-hearted and blue.

I felt that life was meaningless.

A respondent has a score profile of 1, 3, and 2. What is the scale score for this individual?

6

Which of the following variables is measured on an ordinal scale?

Select one:

a. Treatment assignment (treatment vs. control)

b. Number of Facebook friends

c. Ethnicity

d. Education level (less than HS, HS grad, some college, college grad)

d. Education level (less than HS, HS grad, some college, college grad)

Beta-carotene supplements have been thought to protect against cancer. A study published in the Journal of the National Cancer Institute randomly assigned women to receive a beta-carotene supplement or a placebo, and their health was studied over their lifetime. The outcome variable classified women according to whether cancer occurred or not. Which level of measurement describes the outcome variable (cancer vs. no cancer)?

Select one:

a. Nominal

b. Ordinal

c. Continuous

a. Nominal

A depression questionnaire asks the following three items, each of which is measured on a 1 (Strongly disagree) to 5 (Strongly agree) scale.

I felt that I had nothing to look forward to

I felt down-hearted and blue.

I felt that life was meaningless.

A researcher forms a scale score by averaging responses to the three items. What is the minimum value for the scale score?

1

A depression questionnaire asks the following three items, each of which is measured on a 1 (Strongly disagree) to 5 (Strongly agree) scale.

I felt that I had nothing to look forward to

I felt down-hearted and blue.

I felt that life was meaningless

A researcher forms a scale score by summing responses to the three items. What is the level of measurement for this variable?

Select one:

a. Continuous

b. Nominal

c. Ordinal

a. Continuous

The distribution of income in the U.S. has a strong positive skew. Which of the following is true?

Select one:

a. Few people have very low incomes

b. Most incomes are moderate, somewhere in the middle

c. Most incomes are very high

d. Few people have very high incomes

d. Few people have very high incomes

Beta-carotene supplements have been thought to protect against cancer. A study published in the Journal of the National Cancer Institute randomly assigned women to receive a beta-carotene supplement or a placebo, and years later researchers recorded whether the women developed cancer. What role does the cancer vs. no cancer distinction play in this study?

Select one:

a. Confounding variable

b. Control variable (covariate)

c. Outcome (dependent) variable

d. Explanatory (independent) variable

c. Outcome (dependent) variable

A study examining the use of and engagement with Facebook asked participants to report their exact number of friends. Which level of measurement describes this variable?

Select one:

a. Ordinal

b. Continuous

c. Nominal

b. Continuous

A depression questionnaire asks the following three items, each of which is measured on a 1 (Strongly disagree) to 5 (Strongly agree) scale.

I felt that I had nothing to look forward to

I felt down-hearted and blue.

I felt that life was meaningless.

A respondent has a score profile of 5, 3, and 4. What is the scale score for this individual?

12

A depression questionnaire asks the following three items, each of which is measured on a 1 (Strongly disagree) to 5 (Strongly agree) scale.

I felt that I had nothing to look forward to

I felt down-hearted and blue.

I felt that life was meaningless

A researcher forms a scale score by averaging responses to the three items. What is the maximum value for the scale score?

5

Which of the following variables is measured on a nominal scale?

Select one:

a. Minutes spent exercising per week

b. Self-reported health (poor, fair, good, excellent)

c. Number of children in a family

d. Political affiliation

d. Political affiliation

A computer-administered measure of prejudice presents participants with a statement about a particular ethic group and then records the amount of time it takes participants to respond to the prompt. What is the level of measurement for the reaction time variable?

Select one:

a. Continuous

b. Ordinal

c. Nominal

a. Continuous

A study of post-partum depression found that most mothers reported relatively low levels of depression, and higher levels of depression were relatively uncommon. What distribution shape best describes this variable?

Select one:

a. Positively skewed

b. Negatively skewed

c. Uniform

d. Normal

a. Positively skewed

A study of post-partum depression includes a questionnaire item asking mothers to report the number of children in the family. Which level of measurement describes this variable?

Select one:

a. Nominal

b. Continuous

c. Ordinal

b. Continuous

A study of post-partum depression found a relatively even number of mothers with low, moderate, and high depression levels. What distribution shape best describes the depression variable?

Select one:

a. Normal

b. Negatively skewed

c. Uniform

d. Positively skewed

c. Uniform

A study indicates that antioxidants found in blueberries may slow down the process of aging. In an animal study, 19-month-old rats (equivalent to 60-year-old humans) were fed either their standard diet or a diet supplemented by either blueberry, strawberry, or spinach powder. After eight weeks, the rats were given memory and motor skills tests. Although all supplemented rats showed improvement, those supplemented with blueberry powder showed the most notable improvement. What role do the memory and motor skills tests play in this study?

Select one:

a. Confounding variable

b. Outcome (dependent) variable

c. Control variable (covariate)

d. Explanatory (independent) variable

b. Outcome (dependent) variable

Beta-carotene supplements have been thought to protect against cancer. A study published in the Journal of the National Cancer Institute randomly assigned women to receive a beta-carotene supplement or a placebo, and their health was studied over their lifetime. Which level of measurement describes the treatment variable (beta-carotene supplement vs. placebo)?

Select one:

a. Ordinal

b. Nominal

c. Continuous

b. Nominal

A study examining the use of and engagement with Facebook asked participants the following question: "I feel out of touch when I haven't logged onto Facebook for a while." Participants indicated their level of agreement or disagreement using a 5-point Likert-type rating scale ranging from 1 ("Strongly Disagree") to 5 ("Strongly Agree"). Which level of measurement describes this variable?

Select one:

a. Continuous

b. Nominal

c. Ordinal

c. Ordinal

A study indicates that antioxidants found in blueberries may slow down the process of aging. In an animal study, 19-month-old rats (equivalent to 60-year-old humans) were fed either their standard diet or a diet supplemented by either blueberry, strawberry, or spinach powder. After eight weeks, the rats were given memory and motor skills tests. Although all supplemented rats showed improvement, those supplemented with blueberry powder showed the most notable improvement. What role does the diet variable (standard, blueberry, strawberry, spinach powder) play in this study?

Select one:

a. Control variable (covariate)

b. Confounding variable

c. Outcome (dependent) variable

d. Explanatory (independent) variable

d. Explanatory (independent) variable

A distribution of midterm exam scores has a strong positive skew. Which of the following is true?

Select one:

a. Most scores are moderate, somewhere in the middle

b. Most scores are very high

c. Few people have very low scores

d. Few people have very high scores

d. Few people have very high scores

The distribution of income in the U.S. has a strong positive skew. Which of the following is true?

Select one:

a. Most incomes are very high

b. Few people have very low incomes

c. Few people have very high incomes

d. Most incomes are moderate, somewhere in the middle

c. Few people have very high incomes

Which of the following variables is measured on a continuous scale?

Select one:

a. Education level (less than HS, HS grad, some college, college grad)

b. Income (< 30K, 30K-50K, 50K-80K, 80K or higher)

c. Treatment assignment (treatment vs. control)

d. IQ

d. IQ

A study of post-partum depression includes a questionnaire item asking mothers to report the number of children in the family. Most mothers reported having only one child, and the number of mothers reporting 2, 3, and 4 children steadily decreased. What distribution shape best describes this variable?

Select one:

a. Negatively skewed

b. Uniform

c. Normal

d. Positively skewed

d. Positively skewed

A study examining the use of and engagement with Facebook asked participants to report their exact number of friends. Which level of measurement describes this variable?

Select one:

a. Nominal

b. Continuous

c. Ordinal

b. Continuous

A depression questionnaire asks the question, "I felt that I had nothing to look forward to." Respondents answered on a scale ranging from 1 (Strongly disagree) to 5 (Strongly agree). Which level of measurement describes this variable?

Select one:

a. Nominal

b. Ordinal

c. Continuous

b. Ordinal

A popular depression scale classifies people into the following groups: no depression, mild depression, and clinical depression. Which level of measurement describes the depression variable?

Select one:

a. Continuous

b. Nominal

c. Ordinal

c. Ordinal

A national survey of smoking behavior asks respondents to report their family's total household income to the nearest dollar. What is the level of measurement for the income variable?

Select one:

a. Ordinal

b. Continuous

c. Nominal

b. Continuous

A distribution of midterm exam scores has a strong positive skew. Which of the following is true?

Select one:

a. Few people have very high scores

b. Few people have very low scores

c. Most scores are moderate, somewhere in the middle

d. Most scores are very high

a. Few people have very high scores

Beta-carotene supplements have been thought to protect against cancer. A study published in the Journal of the National Cancer Institute randomly assigned women to receive a beta-carotene supplement or a placebo, and their health was studied over their lifetime. The outcome variable classified women according to whether cancer occurred or not. Which level of measurement describes the outcome variable (cancer vs. no cancer)?

Select one:

a. Continuous

b. Nominal

c. Ordinal

b. Nominal

A study of post-partum depression found that most mothers reported relatively low levels of depression, and higher levels of depression were relatively uncommon. What distribution shape best describes this variable?

Select one:

a. Normal

b. Negatively skewed

c. Positively skewed

d. Uniform

c. Positively skewed

Beta-carotene supplements have been thought to protect against cancer. A study published in the Journal of the National Cancer Institute randomly assigned women to receive a beta-carotene supplement or a placebo, and years later researchers recorded whether the women developed cancer. What role does the beta-carotene supplement vs. placebo distinction play in this study?

Select one:

a. Control variable (covariate)

b. Outcome (dependent) variable

c. Explanatory (independent) variable

d. Confounding variable

c. Explanatory (independent) variable

A study of post-partum depression includes a questionnaire item asking mothers to report the number of children in the family. Which level of measurement describes this variable?

Select one:

a. Ordinal

b. Nominal

c. Continuous

c. Continuous

A study examining the use of and engagement with Facebook asked participants about weekly minutes spent logged on. Which level of measurement describes this variable?

Select one:

a. Continuous

b. Ordinal

c. Nominal

a. Continuous

A study examining the use of and engagement with Facebook asked participants the following question: "I feel out of touch when I haven't logged onto Facebook for a while." Participants indicated their level of agreement or disagreement using a 5-point Likert-type rating scale ranging from 1 ("Strongly Disagree") to 5 ("Strongly Agree"). Which level of measurement describes this variable?

Select one:

a. Ordinal

b. Continuous

c. Nominal

a. Ordinal

A study indicates that antioxidants found in blueberries may slow down the process of aging. In an animal study, 19-month-old rats (equivalent to 60-year-old humans) were fed either their standard diet or a diet supplemented by either blueberry, strawberry, or spinach powder. After eight weeks, the rats were given memory and motor skills tests. Although all supplemented rats showed improvement, those supplemented with blueberry powder showed the most notable improvement. What role do the memory and motor skills tests play in this study?

Select one:

a. Confounding variable

b. Outcome (dependent) variable

c. Explanatory (independent) variable

d. Control variable (covariate)

b. Outcome (dependent) variable

Beta-carotene supplements have been thought to protect against cancer. A study published in the Journal of the National Cancer Institute randomly assigned women to receive a beta-carotene supplement or a placebo, and years later researchers recorded whether the women developed cancer. What role does the cancer vs. no cancer distinction play in this study?

Select one:

a. Explanatory (independent) variable

b. Confounding variable

c. Outcome (dependent) variable

d. Control variable (covariate)

c. Outcome (dependent) variable