2. Collecting agromyticin hormonal as a measure of aggression may not be a measure of aggression: (1 point)

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1 Psychology 9A: Fundamentals of Psychological Research Spring 7 Test 1 For this multiple-choice test, ONLY the mark-sense answer sheet will be graded. Be sure to bubble in the VERSION of the quiz and to use a number pencil. SELECT THE SINGLE BEST ANSWER TO EACH QUESTION. Unless otherwise noted, the questions will be worth points each. 1. One step in hypothesis testing involves comparing the p-value associated with the inferential statistic, with the established alpha level (often set to.5). When alpha equals.5, this sets up the likelihood that you ll make a only 5 out of 1 times if the study were repeated 1 times and the null hypothesis were true. a. Type 1 error b. Type error c. Correct decision d. Systematic error The next two questions are based on the following example: A certain hormone, agromyticin, has been shown to be linked to aggressive behavior in blue-haired rats. However, levels of this hormone also vary regularly with time of day. Researchers are interested in testing the aggressiveness of these rats in different social situations, such as during feeding and mating. All blue-haired rats have exactly five blue hairs on the tips of their tails.. Collecting agromyticin hormonal as a measure of aggression may not be a measure of aggression: (1 point) a. reliable b. valid c. neither valid nor reliable 3. Collecting data on the number of blue hairs on the tip of the rat s tail may not be a measure of aggression: (1 point) a. reliable b. valid c. neither valid nor reliable. You believe that listening to a foreign language in your sleep is more effective than learning it in class. To test this hypothesis you compare the performance on a language test between a French class composed of 1 people and another group of 1 people who listen to French tapes while they sleep. You do not find a statistically significantly difference between the two groups (i.e. fail to reject H ). If it is actually a true fact that people CAN learn languages better in their sleep, then you have made a: a. Correct decision b. Type I error c. Type II error d. Alternative hypothesis 5. The formula for a simple regression line is: a. Y = a + bx b. Y = X + b c. M = (X +Y)/N d. Y = a + X 1

2 . We compare the p-value with the alpha level to determine whether the observed data are statistically significantly different from the null hypothesis. If the p-value is greater than alpha =.5, then we hypothesis. (1 point) a. reject the null hypothesis b. fail to reject the null hypothesis c. accept the alternative hypothesis d. fail to reject the alternative hypothesis 7. What happens to the likelihood that a statistic will become significant when the alpha-level is increased? The likelihood of finding a statistically significant finding. a. Increases b. decreases c. stays the same (irrelevant) d. depends on the degrees of freedom The next two questions are based on the following example: A group director at Microsoft wants to maximize her employee s performance. She reads a research article that suggests that performance increases as stress increases, but only up until a point. After a point, performance decreases as stress increases beyond the point.. Based on the scatterplot below, what is the reported Pearson s correlation coefficient likely to be in the research article? (1 point) a. r =.5 b. r =.5 c. r =.5 d. r =. Performance 5 3 Scatterplot Stress Level 9. Based on your understanding of the scatterplot, what do you recommend to the Microsoft group director? a. There is no relationship between stress and performance, so look for another way to motivate your employees besides manipulating stress levels. b. There is a curvilinear relationship between stress and performance, so make the work environment moderately stressful, at most, to maximize employee productivity. c. There is a curvilinear relationship between stress and performance, so maximize the stress level to maximize employee productivity. d. There is linear relationship between stress and performance, so minimize the stress level to maximize employee productivity.

3 1. Which of the following statements is NOT relevant for scientific researchers? (1 point) a. A good theory can be proved to be true. b. A research project can be applied, conducted in the field, and qualitative in nature. c. A typical program of research involves prediction, explanation, and description. d. A scientific question has to be empirically solvable. e. Findings in scientific research should be replicated. 11. In lecture, Dr. Leu said that any inferential statistic was essentially a ratio between systematic and random error variance. This is also represented as: a. Inferential statistic = (Variability within each condition)/(variability between conditions) b. Inferential statistic = (Error Variance)/(Systematic Variance) c. Inferential statistic = (Variability between conditions)/(variability within each condition) d. Inferential statistic = (Systematic Variance/Variability between conditions) 1. There is a true difference between groups A and B. To increase the chance of finding a statistically significant result, with alpha level =.5, researchers should the sample size. (1 point) a. increase b. decrease c. analyze d. calculate the p-value of 13. On which type(s) of measures can Pearson s r be calculated? (1 point) a. Only interval and ordinal measures b. ratio measures c. ordinal measures d. nominal measures e. all types of measures 1. You read an example of developmental psychological research on SmartPsych, adapted from Carlson and Moses (1). The overall Inhibitory Control (IC) battery and the Theory of Mind (ToM) battery were highly correlated (r =.1, p<.1), even after controlling for age, gender, number of siblings, and verbal ability. From this result, the researchers concluded that there is a link between inhibitory control and theory of mind in preschool age children. What could the researchers conclude if the raw correlation between IC and ToM came out statistically significant but not the partial correlation? a. There is a link between inhibitory control and theory of mind in preschool age children. b. There is a link between inhibitory control, theory of mind, age, gender, number of siblings, and verbal ability in preschool age children. c. There is no link between inhibitory control and theory of mind in preschool age children. d. The link between inhibitory control and theory of mind is confounded by age, gender, number of siblings, and verbal ability in preschool age children. 3

4 15. A team of researchers find that the correlation between TV watching (Variable X) and children s aggression (Variable Y) is r =.5. One possible interpretation of this correlation is that large doses of TV-watching causes children to become aggressive. Another interpretation is that already aggressive children watch large doses of TV. The second interpretation is an example of the problem of: (1 point) a. directionality or reverse causation b. third variable c. reciprocal causation d. mediating variable 1. Correlational procedures are important when: a. investigating individual differences in personality traits b. differentiating mental disorders c. studying the heritability of personality traits d. all of the above 17. Which of the following scatterplots is most likely a visual representation of r = -.? (1 point) a. b. Y X Y X c. d Y Y 1 1 X 1 1 X

5 1. Which of the following statements is logically correct when a given statement is true? If a person is a UW student, then s/he will receive a % discount off the purchase of a Psychology 9 textbook at the bookstore. a. A person is a student of Seattle University. Therefore, the person can not purchase the textbook at the bookstore. b. A person purchases the textbook at a % discount at the bookstore. Therefore, the person must be a UW student. c. A person is a student of Seattle University. Therefore, the person can not purchase the textbook at a % discount at the bookstore. d. A person purchases the textbook with a full price. Therefore, the person must not be a UW student. e. None of them is correct. 19. Although a(n) cannot be measured directly, an operational definition provides a specific way to measure it so that researchers can approach the study scientifically. (1 point) a. independent variable b. dependent variable c. construct d. alpha level. If the true state of affairs is that the null hypothesis is TRUE, and a researcher decides to fail to reject the null hypothesis, the researcher has made a: (1 point) a. correct decision b. Type 1 error c. Type error d. systematic error 1. You have been asked to read an empirical article for an assignment in Psychology 9. In the Results section, you read, Results demonstrated that reaction time and pre-frontal cortex activation were positively correlated, r (35) =., p<.5. From this sentence alone, you can conclude that this study definitely: a. used a correlational design b. reported a correlational descriptive statistic. c. reported a correlational inferential statistic d. used a partial correlational design.. Using a data set of over 3, British civil servants, Dr. Adler and her colleagues discovered that as household income increased, health also increased in this sample for every step in the income gradient. Before interpreting this correlation as household income causes health outcomes at all levels, however, they worried whether another interpretation of the data was possible. In particular, they wondered whether household income was causing mood, which was in turn, causing health outcomes (including mental health). This interpretation of the correlational finding suggests a(n): a. mediating variable b. extraneous variable c. third variable d. criterion variable The following description applies to the next two questions. In the 19s, there were many more home runs in baseball than in previous decades. Some experts suggested that this was related to baseball player s salaries: the more home runs they hit, the higher their salaries. To test the hypothesis that the number of home runs is more predictive of salaries than batting averages, researchers analyze data using the following multivariate approach: Salary = a + b 1 HomeRuns + b BattingAverage 5

6 3. If their null hypothesis is b 1 = b, then their alternative hypothesis is: a. there is a positive correlation between salary and number of home runs. b. b 1 = b c. b 1 >b d. b 1 < b. In the researcher s analysis, which variables are the predictor variables and which variables are the criterion variable? a. number of home runs and batting averages are the predictor variables and a is the criterion variable b. number of home runs and batting averages are the predictor variables and salary is the criterion variable c. b1 and b are the predictor variables and salary is the criterion variable d. b1 and b are the predictor variables and Y is the criterion variable The following study is relevant to the next two questions. A student approaches his TA about how to improve his grade in Psychology 9. The student describes that he is studying hours a day for Psychology 9, but admits that he is not getting enough sleep. The TA suggests that getting more sleep may help improve his grade, citing research. When learning occurs, the relationship of activity between neurons is expected to change. Research studies show that sleep facilitates the learning process. For example, in one study, rats were trained to perform the same task. Neuronal activity was measured when the rats performed the task. Then, some fell asleep after learning the task, while others did not. After all the rats were awake, neuronal activity was measured a second time when the rats performed the task again. The magnitude of neuronal activity change from the first to second task performance was compared across rats who slept and those who did not. The rats that slept between task performances showed greater change than the group of rats who did not sleep. 5. What is the best interpretation of the data? (1 point) a. A direct association was observed between sleep and neuronal activity. b. An inverse association was observed between sleep and neuronal activity. c. A positive, linear relationship was observed between neuronal activity and task performance. d. Sleep causes increased neuronal activity change.. What kind of study is this best described as? (1 point) a. field study b. natural groups experiment c. observational study d. strict/true experiment 7. What happens to the likelihood that a statistic will become significant when random error variance is increased? The likelihood of finding a statistically significant finding. (1 point) a. Increases b. decreases c. stays the same (irrelevant) d. depends on the degrees of freedom. in a given data set is either the result of some identifiable factor OR a factor that has not been properly controlled for and that does not cancel out across conditions. (1 point) a. Standard error b. Systematic variance c. Error variance d. Standard deviation

7 The next three questions are based on the following example: A research team has a hypothesis that the regularity of daily meals will affect how long people are willing to devote time to solving difficult problems before giving up. They have subjects come into their lab and work on a complicated puzzle that is technically impossible to solve (though the participants do not know this). The researchers measure how long participants will work on the puzzle before giving up. They then ask the subjects how long it has been between the time they last ate any food and the time they started the puzzle. The data points for each participant and the correlation results are as follows: Participant Hours since last meal Minutes devoted to a difficult task Minutes devoted to a difficult task Relationship of food deprivation on problem solving motivation (r = -.9) Hours since last meal 9. Calculate the coefficient of determination in this example. What is it? (1 point) a. -.9 b. -.9 c.. d. -. a Which of the following sentences best describes the results seen in the scatterplot? (1 point) b. There is a moderate negative correlation between hours since last meal and time devoted to the difficult task. c. There is a strong positive correlation between hours since last meal and time devoted to the difficult task. d. There is a moderate positive correlation between hours since last meal and time devoted to the difficult task. e. There is a strong negative correlation between hours since last meal and time devoted to the difficult task. 7

8 31. Why is the variable Hours since last meal located on the X axis instead of the Y axis? (1 point) a. Because Hours since last meal is the criterion variable b. Because, to make a prediction, we know that the length of time since their last meal was already established before they began spending time on the impossible puzzle. c. Because the predictor variable always goes on the Y axis. d. Because they were asked how long it had been since they last ate after they gave up on the puzzle. 3. A researcher wants to examine the difference between male and female killer whales when it comes to babysitting behavior. She collects data on babysitting for both male and female whales by watching killer whale calves, and documenting which whales spend the most time in close proximity with them. What is the selected independent variable in this study? (1 point) a. babysitting behavior b. whale gender c. number of killer whale calves d. type of whale 33. A researcher studies the relationship between caffeine intake and episodic memory (the outcome variable). He finds that r =. and interprets the result correctly by stating: a. % of mean episodic memory can be explained by mean caffeine intake. b. % of caffeine intake can be explained by episodic memory. c. % of variability in episodic memory can be explained by variability in caffeine intake. d. % of caffeine intake can be explained by episodic memory. 3. The Goodwin textbook describes an important implication of hypothesis testing. Often, nonsignificant findings do not get published. If these non-significant findings are actually Type II errors, then important research outcomes are not becoming known. This phenomenon has been called the: (1 point) a. error variance b. failure to reject H c. the file drawer effect d. missing data 35. Every day in a lecture hall, 5 TAs flipped a coin 1 times and another group of 5 TAs flipped a coin 1 times. On any given day, the percentage of heads the TAs flipped varied around 5%, sometimes above 5% and sometimes below 5%. At the end of the academic quarter (5 days), which group of TAs had more days when they flipped % heads? a. Both groups were the same b. The TAs who flipped a coin 1 times/day c. The TAs who flipped a coin 1 times/day Please do not leave the classroom until after 1:PM so that you don t disrupt other students upon exiting; if you finish early, spend the remaining time checking your answers. HAND IN BOTH YOUR ANSWER SHEET AND THE TEST. Remember to include your name, UWID, bubble in TEST VERSION B, and Instructor s name (LEU) or 5 points will automatically be deducted.