Exam 8: Bivariate Correlational Research

RESEARCH STUDY 8.2: Dr.Moynihan conducts a study examining the relationship between the number of panic attacks a person experienced in the past month, the number of nightmares experienced in the past month, and people's levels of neuroticism (a personality trait characterized by instability, anxiety, and worry).She collects a convenience sample of 50 community college students (25 males, 25 females).Below are her findings. • A (number of panic attacks in the past month and neuroticism): r = .03, not sig. • B (number of panic attacks in the past month and number of nightmares in the past month): r = .14 (p = .05) • C (number of nightmares in the past month and neuroticism): r = .48 (p = .003). How strong is the external validity of Dr.Moynihan's study? How does the fact that she finds no differences in the associations in men and women also speak to the study's external validity?

RESEARCH STUDY 8.1: Dr.Guidry conducts a study examining the relationship between the number of friends one has and the experience of daily stress and life satisfaction.She randomly samples 1,500 elderly men and women in Nashville, Tennessee (the state capital), located in the southern United States.Below are her findings. • Life satisfaction and experience of daily stress: r = .57 (p = .01) • Number of friends one has and experience of daily stress: r = .09, not sig. • Number of friends one has and life satisfaction: r = .36 (p = .04) In determining whether the relationship between two of Dr.Guidry's variables was statistically significant, which of the following must be considered?

What does it mean that an association is "spurious"? What can cause spurious associations?

All of the following are true of outliers EXCEPT:

Why is the size of a sample not as important to external validity as the way a sample was collected?

The temporal precedence criterion is also known as the problem.

Statistical significance depends on which of the following?

Which of the following graph formats is the best way to examine an association claim between a categorical variable and a quantitative variable?

Which of the following is NOT true of finding a stronger effect size in an association claim?

A study finds a correlation coefficient of r = .52.This number gives you information about which of the following?

RESEARCH STUDY 8.2: Dr.Moynihan conducts a study examining the relationship between the number of panic attacks a person experienced in the past month, the number of nightmares experienced in the past month, and people's levels of neuroticism (a personality trait characterized by instability, anxiety, and worry).She collects a convenience sample of 50 community college students (25 males, 25 females).Below are her findings. • A (number of panic attacks in the past month and neuroticism): r = .03, not sig. • B (number of panic attacks in the past month and number of nightmares in the past month): r = .14 (p = .05) • C (number of nightmares in the past month and neuroticism): r = .48 (p = .003). Explain the three associations from Dr.Moynihan's study in terms of direction of each association (a), statistical significance (b), and effect size (c), using Cohen's benchmarks.

RESEARCH STUDY 8.1: Dr.Guidry conducts a study examining the relationship between the number of friends one has and the experience of daily stress and life satisfaction.She randomly samples 1,500 elderly men and women in Nashville, Tennessee (the state capital), located in the southern United States.Below are her findings. • Life satisfaction and experience of daily stress: r = .57 (p = .01) • Number of friends one has and experience of daily stress: r = .09, not sig. • Number of friends one has and life satisfaction: r = .36 (p = .04) Dr)Guidry finds that the relationship between the number of friends one has and life satisfaction is stronger for men than for women.Why might Dr.Guidry have looked for this difference?

RESEARCH STUDY 8.1: Dr.Guidry conducts a study examining the relationship between the number of friends one has and the experience of daily stress and life satisfaction.She randomly samples 1,500 elderly men and women in Nashville, Tennessee (the state capital), located in the southern United States.Below are her findings. • Life satisfaction and experience of daily stress: r = −.57 (p = .01) • Number of friends one has and experience of daily stress: r = .09, not sig. • Number of friends one has and life satisfaction: r = .36 (p = .04) In evaluating Dr.Guidry's study, you question the construct validity of the study.Which of the following questions would you be asking?

Name two ways in which the analysis of an association between two quantitative variables differs from the analysis of an association between a categorical variable and a quantitative variable.

Which of the following is true of moderators?

RESEARCH STUDY 8.1: Dr.Guidry conducts a study examining the relationship between the number of friends one has and the experience of daily stress and life satisfaction.She randomly samples 1,500 elderly men and women in Nashville, Tennessee (the state capital), located in the southern United States.Below are her findings. • Life satisfaction and experience of daily stress: r = .57 (p = .01) • Number of friends one has and experience of daily stress: r = .09, not sig. • Number of friends one has and life satisfaction: r = .36 (p = .04) Considering Dr.Guidry's study, her results could most safely be generalized to which of the following groups?

RESEARCH STUDY 8.2: Dr.Moynihan conducts a study examining the relationship between the number of panic attacks a person experienced in the past month, the number of nightmares experienced in the past month, and people's levels of neuroticism (a personality trait characterized by instability, anxiety, and worry).She collects a convenience sample of 50 community college students (25 males, 25 females).Below are her findings. • A (number of panic attacks in the past month and neuroticism): r = .03, not sig. • B (number of panic attacks in the past month and number of nightmares in the past month): r = .14 (p = .05) • C (number of nightmares in the past month and neuroticism): r = .48 (p = .003). Imagine that Dr.Moynihan finds two outliers.These two people report a very high number of nightmares in the past month and have very high scores on neuroticism.Why should Dr.Moynihan be worried about the presence of these two outliers?

RESEARCH STUDY 8.2: Dr.Moynihan conducts a study examining the relationship between the number of panic attacks a person experienced in the past month, the number of nightmares experienced in the past month, and people's levels of neuroticism (a personality trait characterized by instability, anxiety, and worry).She collects a convenience sample of 50 community college students (25 males, 25 females).Below are her findings. • A (number of panic attacks in the past month and neuroticism): r = .03, not sig. • B (number of panic attacks in the past month and number of nightmares in the past month): r = .14 (p = .05) • C (number of nightmares in the past month and neuroticism): r = .48 (p = .003). Of the three findings in Dr.Moynihan's study, which associations are statistically significant? What does it mean that an association is statistically significant?

Which of the following questions is NOT necessary to ask when interrogating statistical validity?

RESEARCH STUDY 8.2: Dr.Moynihan conducts a study examining the relationship between the number of panic attacks a person experienced in the past month, the number of nightmares experienced in the past month, and people's levels of neuroticism (a personality trait characterized by instability, anxiety, and worry).She collects a convenience sample of 50 community college students (25 males, 25 females).Below are her findings. • A (number of panic attacks in the past month and neuroticism): r = .03, not sig. • B (number of panic attacks in the past month and number of nightmares in the past month): r = .14 (p = .05) • C (number of nightmares in the past month and neuroticism): r = .48 (p = .003). Examining Dr.Moynihan's study and using the three criteria of causation, why can she not say that the number of panic attacks in the past month causes one to have fewer nightmares in the same month?