Exam 14: a Statistical Tools for Answering Research Questions

Fix It Clay is a graduate student who recently celebrated completing his first year of graduate school. The next day Clay felt terrible. This leads him to wonder what the best hangover remedy is. He begins by asking a few of his friends what has worked for them. One friend says a heavy, greasy meal always makes him feel better. Another friend says she takes ibuprofen and pink bismuth. His roommate swears by lots of coffee. Clay decides to test these remedies empirically and his friends eagerly volunteer to participate in his study. Clay's friends consume drinks of their choosing until their blood alcohol content reaches 1.6, twice the legal limit of intoxication. The next day, he serves each of them bacon, eggs, hash browns, and pancakes. Two hours after they eat they complete a survey to assess how sick they feel. Sickness scores vary from 0 = not sick at all, to 50 = extremely sick. Clay repeats this procedure two more times with the same participants. On the second occasion he gives them ibuprofen and pink bismuth, and on the third occasion he serves them coffee. Clay's research is not based on a review of the literature. What do you think about that? What type of research design did Clay create and how should he analyze the data? Do you see any limitations with his methods?

Fix It A psychology student wanted to replicate John Watson's fear-conditioning study for her senior thesis project. After getting permission from her sister, the student introduced a variety of stimuli, including objects and sounds, to her 6-month-old nephew. She found that the baby was not fearful of any stimulus, except for a loud noise she produced by banging pans together. The student recorded that each time she made this loud noise the baby began to cry. She also noted that the baby was particularly fond of a particular stuffed animal. When presented with the stuffed animal the baby would smile and reach for it. The student then began to bang the pans together after the baby was presented with the stuffed animal. Eventually the student noticed that the baby would begin to cry when presented with the stuffed animal, even in the absence of the loud noise. After several weeks of working with her nephew, the student thanked her sister for using her nephew for her project. She wrote up the results and presented them at a regional psychology meeting where to her surprise someone told her she had behaved unethically. What research design is the student using? Is there a problem because she based her study off of Watson's work? What do you think about the ethics associated with this study? How would you change it?

Fix It Mary Jo recently read a research article about deception in research. The author of the article asserts that deception in research is stigmatized, but individuals in research who are deceived report enjoying the experience. Intrigued by this paper, Mary Jo decides to conduct a study to determine how people feel when they find out they have been deceived, and what types of deception are acceptable. To that end, she conducts two studies. In the first study she randomly assigns participants to one of two treatment conditions. Individuals in the deception group are deceived about the purpose of the study in which they volunteer. Individuals in the control group are told the true nature of the experiment. In both conditions the participants study a list of words in a lavender-scented room and their retention of those words is later assessed. The control group are told the lavender scent is to improve learning, but the deception group are told nothing about the lavender scent. In the second study the participants are again divided into two groups: deception and no deception. Participants come to a health clinic to receive a flu shot. Half of the participants get the vaccine whereas the other half gets a placebo shot (although all believe they have been vaccinated). Six months later the researchers disclose that only some of the participants actually got the vaccine. Mary Jo finds that in the first study deception did not negatively affect participants' perception about research. In fact, many who were not told about the lavender scent were excited to learn why it was present because it confirmed their hypothesis of its presence. In contrast, many individuals in the flu study who did not actually get the flu shot were upset about being lied to. Was deception justified in this study? What might an IRB say about how the groups were deceived? Fix it!

Fix It Recently, Hunter watched an episode of a popular television program that found cursing increases pain tolerance to a cold stimulus. He identified a number of flaws in the methodology so he decided to test the effect of cursing on pain tolerance under more controlled conditions. To ensure his sample is random, Hunter posted flyers around the psychology building asking for volunteers for a study about pain. Twenty-three individuals volunteered and each was tested individually. The procedure required them place their hand in an ice bath held constant at 1 degree Celsius and to keep it there for as long as they were able to withstand the pain. After a five-minute rest they repeated this process but this time they were told to yell curse words while their hand was in the ice bath. Hunter measured how many seconds the participants were able to keep their hand in the ice during the two trials. To maintain consistency in his study Hunter always ran the control condition (no cursing) first, and the experimental condition (cursing) second. Hunter found that people were able to keep their hand in the ice bath for a significantly longer time during the cursing condition when compared with the no-cursing condition. Hunter concluded that despite the flawed methodology in the television show's experiment, their results are valid: cursing causes an increase in pain tolerance. What do you think of Hunter's methodology?

Fix It Mrs. Ballard is a high school teacher who hypothesizes that kids involved in extracurricular activities perform better academically. She decides to examine the most recent graduates of the high school where she works. She obtains two measures for all 176 graduates: final GPA, and how many extracurricular activities they participated in throughout their 4 years in school. She analyzes the data using Pearson's r and finds a statistically significant relationship (r(174) = -.78, p < .05). She presents the results to the principal of the school and argues that students should be required to participate in at least two extracurricular activities each year. The principle looks at the results of the study and informs Mrs. Ballard she is mistaken. Mrs. Ballard is confused because the results revealed a statistically significant relationship between the two variables. Discuss Mrs. Ballard's hypothesis. Why do you think the principal disagrees with Mrs. Ballard's conclusion? Fix it!

Fix It Dr. James is interested in knowing what factors best motivate children to perform well in school. He asks his friends to volunteer their children for the study and ends up with 23 children between the ages of 6 and 15 years. He randomly selects 12 children to participate in his first study in which he examines whether money is a good motivator. Half of the kids receive $5 for each A they earn on tests throughout the school year, whereas the other half receive no money. In a second study, Dr. James randomly assigns the students to one of three conditions. In the positive verbal reinforcement group the students' parents praise them for doing well by saying things like "great work" and "I knew you could do it!" In the punishment group students are assigned a menial chore, such as cleaning the house and raking leaves, when their grade on a test is below a B. In the control condition children are neither praised nor punished for their academic performance. Dr. James analyzes the data from the first study by conducting a one-way ANOVA. He concludes that kids who earn money for doing well end up having a higher GPA at the end of the semester than the kids who received no monetary incentive (F(9)=2.72, p > .05). Dr. James also conducts a one-way ANOVA on the second study. His analysis reveals the groups differ significantly (F(9) = 7.25, p < .05). After looking at how each group performs, he states that kids in the reinforcement group end up doing much better in school than the other two groups. There are several flaws with Dr. James' design and analysis. Identify three and discuss how you would fix them.

Fix It Genie is a first-year doctoral student studying clinical psychology at the Adler School of Professional Psychology. She was attracted to this school because of her admiration of Adlerian theory. A central tenant of Adlerian theory is that no one is mentally ill. Rather, Adlerian therapists believe that individuals are driven by social forces and can be motivated to change. Genie wants to know what theories other students at her school admire. To that end, she creates a survey to administer to first-, second-, and third-year doctoral students. Her survey is a brief one-item question that asks "Whose theoretical perspective do you most identify with?" The response alternatives include: Erikson, Freud, Jung, Adler, and Maslow. Genie administers her survey during the holiday party that is held annually for all students, faculty, and staff. This year's party is on December 22, the night following the last final exam. Of the 60 first-, second-, and third-year doctoral students, only 25 attend the party. Of the 25 students, 18 complete the survey. Genie counts the responses by year in school. She finds that 16 identify with Adler, one with Freud, and one with Maslow. Genie concludes that Adlerian theory is the most popular theory among therapists-in-training. This is good news to her and validates her decision to attend the Adlerian School of Professional Psychology. What do you think about Genie's survey? Would you change the survey and how it was administered? Discuss why and describe how.

Fix It The researchers were interested in understanding the effects of illicit drugs on brain functioning. They recruited participants from local Narcotics Anonymous support groups. Thirty-eight former drug users participated in the study. Fifteen reported cocaine as their drug of choice, 10 indicated heroin as their drug of choice, and 13 indicated synthetic marijuana as their drug of choice. After providing basic demographic information (sex, age, ethnicity), the participants consented to a PET scan of their brain to assess cerebral blood flow. The cerebral blood flow of participants in the three drug groups was analyzed using a one-way ANOVA. The results indicated cerebral blood flow was not affected by drug use (F(2, 35) = 1.82, p > .05). The researchers concluded that drug abuse does not affect cerebral blood flow. These results suggest drugs do not affect the brain as once believed. Based on the information provided, do you agree with the researchers' conclusion? What changes in the research design would you need to be able to believe that drugs do not affect cerebral blood flow? Fix it!

Fix It Dr. Massey recently saw a headline on CNN.com that read "Kids Who Are Breastfed Are Smarter." She wanted to conduct a study to determine whether this claim is true. To that end, Dr. Massey, who is affiliated with a university in rural North Dakota, contacted her local hospital to obtain a list of all 172 women who gave birth in 2005. She randomly selected 50 women to take part in the study and 18 agreed to participate. Dr. Massey gave all 18 participants the same survey. There were many questions on the survey, but one was critical to testing her hypothesis. It was phrased to determine whether the mothers fed their babies only breast milk for the first year or fed their babies only formula for the first year. This question was then used to divide her participants into two treatment conditions: Breastfed or Formula-fed. Dr. Massey was very pleased to find that exactly half of the women (n = 9) breastfed their babies for one year, and exactly half (n = 9) formula-fed their babies for one year. To assess intelligence in the children (now 10 years old), Dr. Massey administered an IQ test. Her university does not have access to the most commonly used IQ test so she developed one on her own that she believes to be a comparable assessment of intelligence. Dr. Massey finds that the mean IQ of the breastfed children was 108.5, and the mean IQ of the formula-fed children was 101.0. Based on this information she concludes that breastfeeding does, in fact, causes an increase in intelligence. Dr. Massey developed her research project based on a CNN headline. What do you think of that? What concerns and limitations do you see with Dr. Massey's study? How might you fix them?

Fix It At the end of each month a local reproductive health clinic runs statistics about the number of individuals treated for sexually transmitted diseases. For the past three months they have noticed a huge increase in STD treatment and are worried there is an epidemic in their county. They decide to conduct a program evaluation and begin with focus groups to determine what is contributing to the STD outbreak. During the focus group they find that there is also an increase in drug use among young adults in the community. Knowing that drug use impairs decision making, the health clinic concludes that the increase in drug use is causing the STD outbreak. The health clinic applies for a grant to fund an antidrug program and is surprised when they do not get the money. After hiring a research consultant and reviewing the feedback from the grant reviewers they revise their application and resubmit the grant the next time it is offered. What do you think the feedback from the grant reviewers said? What changes to the grant proposal do you think the health clinic made? Fix it!

Fix It Julio is an undergraduate who has not chosen a major field of study. His friend, Zoe, is a psychology major and has been trying to convince Julio to declare psychology as his major. Julio is reluctant to do so because he believes psychology is not a real science and he's heard the only way you can get a good job in psychology is if you get a master's or doctoral degree. What might you say to Julio about the value of a psychology degree?

Fix It Joey is a sommelier who wants to develop a survey to assess how much his customers know about wine. He writes as many questions about wine he can think of and eventually ends up with 100 items. Joey names the scale the Wine Connoisseur Survey (WCS) and begins to administer it to his customers. Scores on the WCS range from 0 (not knowledgeable) to 100 (extremely knowledgeable). His goal is to identify those customers who are not very knowledgeable about wine so he may get them to enroll in his wine class. Joey decides that he'll ask anyone who scores 50 or less on the scale to take his wine class. To his surprise, very few people score poorly on the WCS. In fact, most people score close to 100. Joey is thrilled to find that so many people are so knowledgeable about wine! Joey's wife, Ava, is a Master's degree student who decides to use Joey's survey in her thesis project. She predicts that people who know more about wine will spend more money on a bottle of wine than people who know relatively little about wine. To that end, she asks patrons of Joey's store to complete the WCS and then measures how much money they spend on a bottle of wine. She finds that people who score a 50 or less on the WCS spend $8 on average on a bottle of wine. In contrast, those who score greater than 50 on the WCS spend $10 on average on a bottle of wine. Based on these results Ava concludes that knowing more about wine leads them to spend more on a bottle. She reasons that people with knowledge are more appreciative of wine and therefore more willing to splurge on a good bottle. Joey presents Ava's results at the upcoming sommelier convention and uses it to promote the WCS. What do you think about Joey's scale? What do you think about Ava's conclusions about how wine knowledge affects how much one spends on a bottle of wine?

Fix It Dave is a second-year graduate student working on his thesis. He predicts that olfaction is an important factor affecting food consumption. To that end, he obtains a group of rats and randomly assigns them to two treatment conditions. The rats in group one receive standard rat chow. The rats in group two receive a rat chow that is manufactured to have no scent. Dave convinces his advisor that he needs research assistants to help him with his study. Dave's advisor calls the director of the university's work-study program who sends two students to work with Dave. One work-study student, Robin, assigned to help Dave also works part-time in the cafeteria. From 9 a.m. to noon she works at Fiesta Cantina, and from 12:30 to 3:00 she works with Dave. The other work-study student, Patrick, has no other responsibilities than to work with Dave. Dave randomly assigned each student to work with one group of rats. Patrick was assigned the control group and Robin was assigned the experimental group. Their job is to give each rat 25 grams of rat chow. After 1 hour they measure how much of the food has been consumed by each rat. The remaining food is removed and the rats are not fed again until the following day. Dave compares the mean amount of food eaten by rats from each group. He finds that rats in the standard chow group consume just as much food as those in the unscented food. Although contrary to his prediction, Dave concludes that food scent is not associated with food consumption. What type of research design did Dave create? Why do you think Dave did not find a difference between the groups? Fix it!

Fix It Dr. Inyang is a counselor whose colleagues have gotten positive results with music therapy. Next week he is beginning a new grief therapy group and decides it is the perfect time to test whether music helps people progress through the grieving process. There are five patients in the group. At the beginning of all 9 sessions Dr. Inyang has each complete the Grief Questionnaire. This questionnaire indicates how much grief one is experiencing, with higher scores indicating more grieving. During the first three sessions Dr. Inyang conducts the group without music, as he has typically done in the past. During the next three sessions he plays calming music during the hour-long session. During the last three weeks Dr. Inyang does not play music. Dr. Inyang uses the results of the Grief Questionnaire obtained during the last session to develop a long-term care plan for each patient. He is surprised to find so many of his patients experiencing high levels of grief despite the fact that almost everyone reported less grief during the fourth through sixth weeks of treatment. This leads Dr. Inyang to question the claims of his colleagues who swear music is therapeutically beneficial. Identify and describe the design of this study. Do you agree with Dr. Inyang that there is not a causal relationship between music and grief reduction? How and why would you change the design?

Fix It Dr. David Snowden started the "Nun Study" in 1986 in Minnesota. It is an ongoing study that tracks a group of nuns whose incidence of Alzheimer's disease is significantly lower than that of the general public. According to Dr. Snowden, the nuns may have been protected against cognitive decline because their lifestyles have been physically and mentally stimulating. After reading about Dr. Snowden's study, Fred decides to use an animal model to examine the effect of lifestyle on cognitive function. To that end, he divides rats into two treatment conditions. In the control condition rats are raised individually in standard laboratory cages. In this type of environment rats have no social interaction and are limited in their ability to engage in physical activity. In the other group rats are house communally where they have access to running wheels and a variety of objects to explore. After 30 days in their respective conditions, Fred examines how well the animals are able to learn a maze. Performance on the maze is indicative of cognitive function. Fred finds that rats in the environmentally rich environment learn the maze significantly faster than rats in the control condition. Based on these results, Fred concludes that stimulus-rich environments improve cognitive function and protect against age-related decline. Identify and describe the variables that are manipulated and measured in this study. What type of research design was used and how should the data be analyzed? What more evidence might you need to convince you that a stimulus-rich environment is advantageous?

Fix It Kristen is approaching her 30^th birthday and is worried because she is still single. She's tried to meet men at bars, the gym, and through several online dating sites all with no luck. Her friend, Beth, is a graduate student pursuing a degree in sexology. Beth recently read an article in Cosmopolitan that reported men find women who wear high-heeled shoes more attractive than those who wear flats and that the height of one's shoe was related to whether a man would approach a woman. Beth decides to test whether there is credence to the idea that shoe height is related to attraction and uses Kristen as her guinea pig. She thinks Kristen is the perfect person to study since she often wears shoes with three different heel heights during a single day. She wears flats while at the gym in the morning, 1.5 inch heels at work during the day, and 3-inch heels in the club at night. One day when Kristen is wearing the three types of shoes Beth records how men behave toward her. Each man who approaches Kristen receives a score on a 100-point scale, with higher scores reflecting more attraction. The next day Beth analyzes the data. She finds that three men approached Kristen at the gym and the mean attraction score was 15. Only one man approached Kristen at work and his attraction score was five. Twenty-two men approached Kristen at the club and the mean attraction score was 68. Beth performed independent t-tests to determine whether the attraction scores differed between the treatments. The results confirmed that men were significantly more attracted to Kristen when she wore very high heels. Kristen concludes that the article about attraction and heel height in Cosmopolitan is scientifically credible. She decides to renew her subscription for three more years. Beth developed her research project based on a Cosmopolitan article. What do you think of that? What concerns and limitations do you see with Beth's study? Fix it.

Fix It Donna has two children whose teachers laud their good behavior. While Donna knows she has great children, she also knows they do not always behave perfectly at home. Donna hypothesizes that children behave better for others than they do their own parents. She decides to do a study in which she examines the behavior of children in their home environment and in their school environment. Discuss the issues of control and ecological validity as it relates to Donna's study. What issues may Donna face with regard to studying children? How might she minimize these issues?

Fix It Dr. Noble is a college professor who wants to know whether text anxiety is related to test performance. At the beginning of the semester she administers the Beck Anxiety Inventory (BAI) to all of the students in each of her three classes: Psychological Statistics, Experimental Psychology, and Brain and Behavior. At the end of the semester she calculates each student's mean exam score. She analyzes the data using Pearson's r and finds a statistically significant positive relationship. As students' anxiety increases, their test performance decreases (r(88) = -.68, p < .05). Dr. Noble conducts another study the following semester. Like the previous semester, she administers the BAI to each of the students in her three classes: History of Psychology, Learning and Behavior, and Personality Theories. She also calculates the students' mean exam scores at the end of the semester. However, this semester she attempts to reduce test anxiety in her students by diffusing sweet orange essential oil throughout the classroom on the exam days. Dr. Noble examines the relationship between BAI scores and test performance and finds the two are not significantly related (r(103) = .18, p > .05). She then performs a paired t-test to determine whether test scores obtained in the first semester (no essential oil) differ from test scores obtained in the second semester (sweet orange oil) and finds a statistically significant difference (t(194) = 5.32, p < .05) with student exam scores being greater in the essential oil condition. Dr. Noble presents the data at a regional psychology conference where she reports that anxiety causes students to perform poorly on exams and advocates for the use of essential oils in the classroom. What problems exist with this study? Fix them!

Fix It Selena is a first-year graduate student pursuing a degree in School Counseling. She's struggling with her Research Methods class. While talking with her professor, Selena says that she doesn't see the importance of research methods since as a school counselor she won't be conducting research. She also discusses her class project with her professor. Selena wants to study something related to her profession. After seeing so much bullying in her school lately, Selena decides to do something related to bully prevention. She thinks that an intervention program may be more effective than counseling children after bullying has occurred. If you were Selena's professor how would you respond?

Fix It Charity is a graduate student who is using a transgenic mouse model of frontotemporal dementia to study Alzheimer's disease. She obtains 30 mice and divides them into three treatment conditions. In the first condition 10 rats are housed communally to assess the impact of social support on the disease. In the second condition 10 rats are housed individually. In the third condition rats are housed individually but have wheels attached to their home cages so they may voluntarily engage in exercise. After one month in their respective conditions Charity sacrifices the animals and examines their brains for the presence of insoluble protein aggregates in the frontotemporal lobe. She obtains five random slices of tissue from each animal's brain and applies a stain to identify the presence of protein. For each animal, the mean amount of protein across the five slices is obtained. Charity is a second-year graduate student who has not yet taken statistics so she is at a loss for how she should analyze the data. She decides to talk to her peers to get their advice on how to proceed. Identify and discuss the research design Charity employed. How should her colleagues suggest she analyze the data? Lastly, discuss the ethics associated with using animals in research.