Which Statistical Test?
A psychologist is interested in whether or not handedness is related to gender. Specifically she wants to know if the percentage left-handed men in the population is different from the percentage of left-handed women. She collected data on handedness for 200 men and 200 women. What type of statistical test would be appropriate?
Chi-Square Test of Independence
Is there a relationship between watching violent TV shows at age 9 and aggressiveness rating by peers at age 15?
Correlation
Logan looked at the memory of expert musicians. He compared expert musicians to people with no musical training on their short-term memory span (how many random numbers they could recall).
Independent samples t-test
How could you test whether Quiz #2 scores predict scores on the final exam?
Regression
Which of the following ANOVAs is used for an experimental design that does NOT have any within-subject conditions?
Two-way between-subjects ANOVA
A one-way, repeated-measures ANOVA is also known as:
Within-groups ANOVA
Meier investigated the persuasiveness of different types of anti-smoking campaigns. One campaign relied on an emotional appeal, and the other campaign relied on a factual appeal. Two hundred smokers read one or the other appeal. Half the smokers had started smoking before age 16, and half started smoking after age 20. Each smoker rated the likelihood that they would stop smoking on a scale from 1 (very unlikely) to 9 (very likely)
2 x 2 factorial ANOVA (between subjects design)
Twenty-five years ago the psychology department reported 153 men as psychology majors and 104 women. You are interested in whether women are a greater proportion of majors this year than they were 25 years ago. Which statistical test would help you answer this question?
Chi-Square
A psychologist is interested in comparing the demographics of grand jury members to demographics of the population to see if grand jury panels are really representative of the population. The first variable she examines is age. The percentage of people over 65 in the population is 25%, but out of 200 people empaneled for grand jury trials, 76 (38%) were aged 65 or more. She wants to know if the proportion of people over 65 on grand juries is significantly different than that proportion in the population. What test should she use?
Chi-Square Goodness of Fit
Your GTFs believe that PSY 302 students' favorite statistical test is the z-test. They decide to survey one of the lab sections, asking students to pick their favorite statistical test out of the 12 we've studied. Which test would be used to determine if students prefer some statistical tests more than others?
Chi-Square Goodness of Fit
How could you tell if grade distribution (number of As, Bs, Cs, Ds) for PSY 302 students differs between terms (Fall, Winter, Spring) of this academic year?
Chi-Square, Test for Independence
In a multiple choice test with 30 questions, 4 options per question, Lucas answered 10 questions correctly. Are we confident he knew anything at all?
Chi-square goodness of fit
A developmental psychologist is interested in whether 2-year-olds have a preference among the three primary colors: red, blue, and yellow. He samples n = 70 2-year-olds, has each child pick her/his favorite color, and records the choices. Which test?
Chi-square goodness of fit: equal proportions
Lowanski wanted to link academic performance with individual differences. Each participant took a Big Five personality test and was categorized as high on conscientiousness or low on conscientiousness. Participants also reported whether their GPA was above or below 3.0.
Chi-square test for independence
The U.S. Census states that 50% of all marriages end in divorce. You survey 60 faculty members (of late-middle age) and find that 25 are divorced and the rest are still married.
Chi-square test of goodness-of-fit
Does the number of syllables influences memory for words? I tried to memorize 50 words. Twenty-five of the words were one-syllable words and 25 are three-syllable words. I remembered 15 of the single-syllable words and 8 of the three-syllable words.
Chi-square test of independence
Parm and Ritter investigated the relationship between birth order and perfectionism. They found 20 first-born, 20 middle, and 20 third-child children. They asked the parents to categorize each child as being a perfectionist or not.
Chi-square test of independence
A psychologist investigating the relationship between SAT score and academic success found that students with high SAT score were more likely to experience academic success. You pointed out to her that students who have high IQ's tend to have high SAT scores and also tend to experience academic success. You explain that the relationship between SAT score and academic success might be due to the fact that both academic success and SAT are related to IQ. If the psychologist has IQ scores for her sample, how could she estimate the relationship between SAT scores and grades for students who are equivalent on IQ?
Correlation
A psychologist is interested in the relationship between job satisfaction and stress. Within a large corporation, the psychologist asked a random sample of workers two questions. The first question asked workers to rate their overall satisfaction with their job on a scale from 1 to 50. The second question asked the workers to rate their stress level during the past week on a scale from 1 to 50. What type of statistical test best assesses the relationship between job satisfaction and level of stress?
Correlation
Charlotte has been dating her new partner, Anna, for one month, and she thinks the relationship is going extremely well. Being a curious scientist, Charlotte wants to know whether there is a relation between her mood and the numbers of hours she spends in a day with Anna. Charlotte has been recording her daily moods (for another project) on a 1 to 10 scale (10 indicates extremely happy) and she is also keeping a diary so she can look up how many hours each day in the last months she spent with Anna. Which test?
Correlation
How would you know if athletes' height is related to their speed?
Correlation
In order to better understand the basis for conduct disorders in 10-year-olds, researchers had mothers rate how fussy their child was in the first year of life. Teachers rated each 10-year-old child's degree of conduct disorder on a 7-point scale.
Correlation
Suppose a researcher is interested in whether there is a relationship between the amount of caffeine consumed and the number of words recalled from a list. Which test?
Correlation
Wagner and Primiano investigated whether "road rage" was related to neuroticism. They had participants take a "road rage inventory" (a real test that measures irritability) and a neuroticism inventory. Which test to use?
Correlation
You want to know if there is a relationship between the number of references a student puts in a paper and the grade on the paper. You collect 40 papers. The number of references varied from 1 to 7. Grades on the papers ranged from 1, which is an F, up to 10, which is an A+.
Correlation
A researcher assigns participants in a research study to sit, stand, or do jumping jacks while solving difficult math problems. Additionally, participants must do the problems either with or without a calculator. It is unclear what the researcher hopes to learn from this experiment. Which statistical test should the researcher use to see whether body position (sit/stand/jumping jacks) and calculator use affect problem-solving speed?
Factorial ANOVA
A researcher is interested in the effects of personality and noise level on task performance. The researcher randomly selects introverts and extraverts for the personality variable. He places half of the participants in a quiet room, and the other half in a noisy room. He then measures how many errors participants make in the task. Which test?
Factorial ANOVA
Many studies have reported gender differences in dream recall. The current study looked at differences between men and women in dream recall by age group. Twenty-eight children, 32 adolescents, 40 young adults, and 38 older adults recorded their dream recall for one month.
Factorial ANOVA. (between subjects design)
A researcher is interested in the relationship between socio-economic status (SES) and domestic violence. She believes that there is a greater incidence of domestic violence in households below the poverty line. To assess this relationship, she surveys a random sample of American adults and asks two questions. First participants are asked to estimate their household income. Later in the survey participants are asked if there has been any physical violence between members of their household (Yes or No). How could the researcher determine whether there is a relationship between SES and incidence of domestic violence?
Independent Samples t-test
An institutional researcher at a large university wants to compare the mathematical abilities of its male and female students. A researcher selects 100 men and 100 women at random from each of the four classes, and administers a standardized mathematics test. The men average 500 on the test, with a standard deviation of 120. The women average 450 on the test, with a standard deviation of 110. What test would be appropriate to determine whether the difference between men and women is real or due to chance variation?
Independent Samples t-test
Imagine you are a researcher interested in sex differences in student's attitudes toward homosexuals. Specifically, you want to test the idea that women are more accepting of homosexuals and thus have more positive attitudes toward homosexuals than do men. You collect data from 10 men and 10 women using a scale that measures homophobia.
Independent Samples t-test
A researcher is interested in the relationship between the consumption of different types of burritos and reported hunger levels after eating. She collects a sample of 20 people who ate bean and cheese burritos and another sample of 26 who ate beef and cheese burritos and then collects reported hunger levels on a scale of 1 to 10. Which test should she use to determine if there is a difference in hunger levels between those that ate bean burritos and those that ate beef burritos?
Independent t-test
A researcher wants to know whether men and women differ in how much they enjoy watching dance performances (on a scale 1 to 7). Which test will they likely use?
Independent t-test
A researcher wants to know whether culture is related to the self- serving bias. She collects data from a group of U.S. students and a group of Chinese students. She has all participants complete a standard self-serving bias questionnaire (using a continuous scale), and tests which culture has a greater self-serving bias. Which test?
Independent-samples t-test
What is the expected grade on the final exam for someone who scored 75% on Midterm 2 and spent 8 hours preparing for the exam?
Multiple regression
A car company claims that their fleet of Eco-Friendly Economy Car have an average of 37 mpg. You randomly sample and test drive 10 Eco-Friendly Economy Cars from local car dealerships and find that the average mpg is 28. Which statistical test should you use to determine if 28 is significantly different from 37?
One-Sample t-test
A researcher believes that recall of verbal material differs with the level of processing. He divided his subjects into three groups. In the low processing group, participants read each word and were instructed to count the number of letters in the word. In the medium processing group, participants were asked to read each word and think of a word that rhymed. In the high processing group, participants were asked to read each word and try to memorize it for later recall. Each group was allowed to read the list of 30 words three times, then they were asked to recall as many of the words on the list as possible. If the researcher wants to know whether the three groups have different amounts of recall, what type of statistical test should be used?
One-Way ANOVA
How would you determine whether dog owners, cat owners or tarantula owners have the highest IQ?
One-Way Between-Subjects ANOVA
Smith and Britton hypothesized that depressed people spend less time in REM sleep. The APA reports that the average person spends about 60 minutes in REM sleep per night. Smith and Britton recorded the REM sleep of 24 depressed patients and found that they were in REM an average of 37 minutes per night with a standard deviation of 10 minutes.
One-sample t-test
The PSY 302 instructors would like to know if student excitement for statistics differs for students who take PSY 302 in fall, winter, spring, or summer. What test should we use?
One-way ANOVA
How does liking specific piece of music relates to exposure? One group heard each piece of music twice, one group heard each piece 8 times, and one group heard each piece 32 times. At the end of the experiment, participants rated how much they liked each piece.
One-way, between-subjects ANOVA
A psychologist is interested in attitudes towards the disabled. She believes that contact with someone who is disabled might have an effect on peoples' attitudes. To test her hypothesis, she measured attitudes toward the disabled both before and after contact with an individual in a wheelchair. What type of statistical test should she use to determine if contact with a disabled person changes peoples' attitudes toward the disabled?
Paired t-test
A researcher is measuring participants reaction time when they are naming emotionally neutral (e.g., "pen") vs. emotionally arousing (e.g., "gun") objects. What test will they use to decide if emotional arousal affects reaction times?
Paired t-test
Durrett investigated the effects of antidepressants on self-harm (cutting). Her participants were young adult female twins with a history of self-harm. One twin was given antidepressants, and the other was given a placebo. Self-harm incidence rates were calculated for each participant.
Paired t-test
Individuals suffering from SAD (seasonal affect disorder) were given Big Five personality tests once during the winter season (during the SAD months) and once during the summer. Their neuroticism scores for each season were compared.
Paired t-test
The food from a local restaurant has been giving people headaches. To be sure, you have a group of friends rate their headache on a scale from zero (no headache) to 10 (you are not friends anymore) both before and after eating at this restaurant.
Paired t-test
A psychologist wants to investigate the relationship between stress and mental health during the first year of college. The researcher developed scales that measure 1) the frequency of stressful events, 2) the perceived importance of these events, 3) the desirability of such events, and 4) the impact of these events of the student. The researcher had 150 first year college students fill out this questionnaire as well as a Symptom Checklist, which is designed to assess the presence or absence of psychological disorders. What statistical procedure would help this researcher discover if psychological disorders can be predicted from the different aspects of stress that have been measured?
Regression
A researcher is interested in testing two interventions designed to reduce racist graffiti in an inner city area. He recruited ten neighborhoods that have a problem with racist graffiti and asked assistants from the community to provide measures of the square feet of new racist graffiti each week. After four weeks of baseline recording, a six week sensitivity training workshop was begun in five of the ten neighborhoods and an advertising campaign was conducted in the other five neighborhoods. Community members continued to measure the extent of any new racist graffiti each week, yielding data from the 10 neighborhoods for 10 consecutive weeks, 4 prior to workshops and 6 after workshops began. The researcher wants to know if the interventions reduced the amount of new racist graffiti and if they differed in any effect. What statistical technique would you advise?
Repeated Measures ANOVA
A political consultant gathers a focus group of 30 registered voters and records their favorability ratings for a particular candidate on a 7-point scale. The consultant gathers favorability ratings from these 30 voters again after each of several televised debates. How would the consultant determine if the candidates' favorability ratings changed across the debates?
Repeated-Measures ANOVA
You've noticed that it's getting warmer outside. To confirm this, you pick a sample of n = 10 Oregon cities. For each city, you look up the high temperature for yesterday, for one week before yesterday, and for two weeks before yesterday. Which test would you use to determine if the temperature is changing significantly from week to week?
Repeated-Measures ANOVA
An exercise physiologists wants to predict number of pounds gained between ages 30 and 35 from the number of TV watching hours per week at age 30
Simple linear regression
