PSYCH210 Henriques final

A researcher is examining the relation between patrol location (more affluent vs. less affluent neighborhoods) and amount of training (5 weeks, 10 weeks, or 15 weeks) to police job performance in a large city. The researcher finds that the officers trained less performed significantly better in the upper-class neighborhood, whereas the officers trained more performed significantly better in the lower-class neighborhood. What type of effect is this? A. quantitative interaction B. qualitative interaction C. main effect of training length only D. main effect of patrol location only

A. quantitative interaction

A researcher examines the effectiveness of different body lotions by having 12 participants apply four different lotions to the same, unique body locations daily for two weeks. For example, lotion #1 is always applied to the right thigh, while lotion #2 is applied to the right upper arm. The participants were randomly selected at a drugstore in a busy area. Which assumption for the ANOVA is met? A. random selection B. normal population distributions C. homoscedasticity D. order effects

A. random selection

When determining the critical value or cutoffs for the three effects tested in a two-way between-groups ANOVA, what value is always the same for each effect? A. within-groups degrees of freedom B. degrees of freedom for columns C. degrees of freedom for rows D. degrees of freedom for the interaction

A. within-groups degrees of freedom

A researcher compares bone density in retired professional athletes across three different sports. He computes a series of three t tests to examine all between-group differences, running each test with a p level of 0.01. What is the probability of a Type I error when making these comparisons? A. 0.03 or a 3 percent chance B. 0.01 or a 1 percent chance C. 0.000001 chance, so small it is not cause for concern D. 0.9703 or a 97 percent chance

A. 0.03 or a 3 percent chance

A researcher examines the effectiveness of different body lotions by having 12 participants apply four different lotions to the same, unique body locations daily for two weeks. For example, lotion #1 is always applied to the right thigh, while lotion #2 is applied to the upper right arm. The participants were randomly selected at a drugstore in a busy area. What is the research hypothesis for this study? A. Differences exist between the average effectiveness assessments of each lotion. B. Lotions cause differences in skin quality across locations. C. The effectiveness of the four different lotions is the same, on average. D. The lotions are the same in terms of effectiveness.

A. Differences exist between the average effectiveness assessments of each lotion.

A researcher reports the results of an interaction in a two-way between-groups ANOVA as: F (1, 80) = 2.83. What decision should be made based on the value of this test statistic? A. Fail to reject the null hypothesis and conclude there is no support for a combined effect of the variables. B. Fail to reject the null hypothesis and conclude the interaction should be investigated with bar graphs. C. Reject the null hypothesis and conclude post hoc tests are needed. D. Reject the null hypothesis and conclude the effect of one variable changes across levels of the other variable.

A. Fail to reject the null hypothesis and conclude there is no support for a combined effect of the variables.

A researcher conducts a within-groups ANOVA, fails to find a significant F statistic for the independent variable, and finds an R2 value of 0.02. What does the effect size statistic tell the researcher about the research? A. The conventions for R2 indicate that this is a small effect, which would help to explain the nonsignificant F statistic. B. This is a small effect and a significant F statistic will only be calculated if sample size is small. C. The conventions for R2 indicate that this is a medium effect, which would encourage the researcher to collect more data in order to detect a genuine significant finding. D. The conventions for R2 indicate that this is a large effect, and the researcher should recheck his or her math for the F statistic.

A. The conventions for R2 indicate that this is a small effect, which would help to explain the nonsignificant F statistic.

When researchers use ANOVAs to report results of case studies that include only one participant, they typically violate the assumption of random selection. How does this action affect the conclusions of the study A. The external validity is low, and they cannot generalize their results beyond the sample. B. The test is robust, and they can generalize their results beyond the sample. C. The external validity is low, but they don't need to report violations of assumptions. D. The results are completely worthless and should not be reported.

A. The external validity is low, and they cannot generalize their results beyond the sample.

Which statement BEST describes an interaction in a two-way ANOVA? A. The two independent variables have a combined effect on the dependent variable hat is not present with either independent variable alone. B. Both independent variable have a main effect. C. No variable has a main effect. D. The study is a within-subjects design, so all participants receive all levels of each independent variable.

A. The two independent variables have a combined effect on the dependent variable hat is not present with either independent variable alone.

Which statistical analysis can handle multiple measures or repeated measures based on the same individuals? A. one-way within-groups ANOVA B. one-way between-groups ANOVA C. paired-samples t test D. independent-samples t test

A. one-way within-groups ANOVA

The Educational Testing Services (ETS) is conducting a study to determine the relation between method of presentation (standard lecture vs. computer presentation) and type of lecture (psychology, English, or statistics) to lecture comprehension. How would we describe the design? A. one-way ANOVA B. 2 X 3 between-groups ANOVA C. 2 X 3 within-groups ANOVA D. 1 X 2 between-groups ANOVA

B. 2 X 3 between-groups ANOVA

For an F distribution with 3 degrees of freedom between and 32 degrees of freedom within, how many groups are being compared and how many participants are in each group, assuming equal numbers of participants per group? A. 2 groups, 8 participants in each group B. 4 groups, 9 participants in each group C. 3 groups, 10 participants in each group D. 4 groups, 32 participants in each group

B. 4 groups, 9 participants in each group

In a two-way ANOVA, three _____ statistics are calculated. A. z B. F C. t D. R2

B. F

A researcher found a significant result using a one-way ANOVA to compare the mean of four age groups (3 years old, 5 years old, 8 years old, and 12 years old) on a test of language ability. What specific conclusions can the researcher draw from this result? A. The 12-year-olds scored higher on a test of language ability than the 3-, 5-, and 8-year-olds did. B. Language ability of 3-, 5-, 8-, and 12-year-olds was not the same. C. Language ability of 3-, 5-, 8-, and 12-year-olds did not differ. D. On a test of language ability, 3-year-olds scored lower than 5-, 8-, and 12-year-olds did.

B. Language ability of 3-, 5-, 8-, and 12-year-olds was not the same.

Which statement is NOT an assumption of an ANOVA? A. The samples should be randomly selected. B. The samples should be from a population with a known mean and standard deviation. C. The samples should be from a normally distributed population. D. The samples should be from populations with approximately the same variance.

B. The samples should be from a population with a known mean and standard deviation.

A researcher rejects the null hypothesis after using an F table to determine the significance value. What can be concluded? A. There is a difference between means that we expected just by chance. B. There is a difference between means that is larger than we would predict by chance. C. There is no difference between means, which is what we would expect by chance. D. There is no difference between means.

B. There is a difference between means that is larger than we would predict by chance.

The Educational Testing Services (ETS) is conducting a study to determine the relation between method of presentation (standard lecture vs. computer presentation) and type of lecture (psychology, English, statistics) to lecture comprehension. What kind of ANOVA should ETS use and what are the factors and/or levels? A. One-way ANOVA: Factor 1 is lecture, with two levels (presentation vs. lecture type). B. Two-way ANOVA: Factor 1 is presentation, with two levels (standard vs. computer), and factor 2 is lecture type, with three levels (psychology, English, and statistics). C. Three-way ANOVA: Factor 1 is presentation, with two levels (standard vs. computer), factor 2 is lecture type, with three levels (psychology, English, and statistics), and factor 3 is lecture comprehension. D. Higher-order ANOVA: Factor 1 is standard presentation, factor 2 is computer presentation, factor 3 is psychology lecture, factor 4 is English lecture, and factor 5 is statistics lecture.

B. Two-way ANOVA: Factor 1 is presentation, with two levels (standard vs. computer), and factor 2 is lecture type, with three levels (psychology, English, and statistics).

Which of these is a potential problem with a matched-groups design for ANOVA? A. Participant loss in one group can cause increase in participants overall. B. We may not be aware of all of the important variables of interest. C. Time commitment for participants is low. D. Statistical power is reduced.

B. We may not be aware of all of the important variables of interest.

What does a two-way ANOVA offer beyond what two separate one-way ANOVAs can tell about the data? A. clarification on how one variable is correlated with another variable B. a chance to see how the effect of one variable can depend on the levels of another variable C. information about the primary effect of one variable as the cause of another D. quantitative assessment of main effects

B. a chance to see how the effect of one variable can depend on the levels of another variable

A marginal mean in a two-way ANOVA is the mean of the dependent variable: A. at one level of an independent variable, given a unique level of the second independent variable B. at one level of an independent variable, disregarding the distinction of levels of the other independent variable. C. across all cells, for all participants. D. in one given cell, which represents a unique experimental condition.

B. at one level of an independent variable, disregarding the distinction of levels of the other independent variable.

Within-groups variability is reduced in the one-way within-groups ANOVA because: A. measurement precision can be maximized when you use the dependent measure on the same participants. B. by using the same participants across all levels of the independent variable, we have removed differences between groups due to individual variability. C. focusing on only one variable in the study allows for reduced variability. D. within-groups studies have lower participant drop-out rates than between-groups studies.

B. by using the same participants across all levels of the independent variable, we have removed differences between groups due to individual variability.

Following a one-way within-groups analysis of variance that results in a significant F statistic, the researcher should: A. replicate the research with matched groups. B. conduct post hoc tests to determine where the significant differences between levels of the independent variable exist. C. conduct planned comparisons to explore where differences may exist when you are unsure. D. conduct a power analysis.

B. conduct post hoc tests to determine where the significant differences between levels of the independent variable exist.

One benefit of using a multifactorial ANOVA with two or more factors is that it can detect _____ among the variables, whereas multiple direct comparisons of means cannot. A. violations of assumptions B. interactions C. a main effect D. significant differences

B. interactions

The multiple-group equivalent of a paired-samples t test is the: A. one-way between-groups ANOVA. B. one-way within-groups ANOVA. C. mixed design ANOVA. D. matched groups design.

B. one-way within-groups ANOVA.

An advantage of the one-way within-groups ANOVA is that researchers can: A. use a nominal or ordinal dependent variable. B. reduce within-groups variability by having the same participants in each group. C. use a scale independent variable. D. perform hypothesis testing but cannot measure effect size.

B. reduce within-groups variability by having the same participants in each group.

After a researcher _____ the null hypothesis, the researcher should conduct a(n) _____ to determine which means are statistically significantly different from each other. A. fails to reject; post hoc test B. rejects; post hoc test C. fails to reject; effect size test D. rejects; effect size test

B. rejects; post hoc test

It is helpful to represent the main effects and interactions of a factorial ANOVA graphically in a bar graph because when lines are drawn to connect the bars, they will be _____ if there is a main effect and _____ if there is an interaction. A. separate but parallel; flat B. separate but parallel; intersecting C. intersecting; flat D. flat and parallel; intersecting

B. separate but parallel; intersecting

The subjects sum of squares calculated in the one-way within-groups ANOVA assesses: A. how much participant data vary as a function of the independent variable. B. the variability due to participant differences. C. the inconsistency of subjects' responses. D. variability for the entire study, across all conditions.

B. the variability due to participant differences.

Which source of variability does not require the grand mean in its calculation? A. between-groups sum of squares B. within-groups sum of squares C. sum of squares for the interaction D. total sum of squares

B. within-groups sum of squares

A researcher interested in the impact of "dress-down Fridays" on work performance decides to study the impact of attire at work. She randomly selects 35 people at a large company to participate. Across the course of three weeks, she has all 35 participants experience working under three different levels of work attire: casual, dress-casual, and formal attire. How many post hoc tests will be needed to determine where significant differences occurred? A. 1 B. 2 C. 3 D. 4

C. 3

A researcher examines the effectiveness of different body lotions by having 12 participants apply four different lotions to the same, unique body locations daily for two weeks. For example, lotion #1 is always applied to the right thigh, while lotion #2 is applied to the upper right arm. How many post hoc tests will be needed to determine where significant differences occurred? A. 3 B. 4 C. 6 D. 8

C. 6

The Educational Testing Services (ETS) is conducting a study to determine the relation between method of presentation (standard lecture vs. computer presentation) and type of lecture (psychology, English, or statistics) to lecture comprehension. How many cells are in this design? A. 2 B. 5 C. 6 D. 12

C. 6

Which distribution allows various types of statistical analyses to be made and is the most complex? A. z B. t C. F D. T

C. F

Rousseau visually inspects her data before analyzing it only to find that the populations that she sampled appear to have very different variances although her sample sizes are equal. Which assumption of ANOVA has she violated and what should she do? A. Heteroscedasticity; she should analyze the data as is but not report it. B. Heteroscedasticity; she should report it with her statistics after analyzing the data. C. Homoscedasticity; she should proceed as long as the largest variance is not greater than two times the smallest variance and report it with her statistics. D. Homoscedasticity; she should substitute some of the data points with the mean of each sample.

C. Homoscedasticity; she should proceed as long as the largest variance is not greater than two times the smallest variance and report it with her statistics.

Dore is measuring the effects of three different therapy techniques on several dependent variables, including scores on a variety of scales measuring depression, anxiety, life satisfaction, and self-image. What type of statistical analysis should she perform? A. two-way ANOVA C. MANOVA C. ANCOVA D. MANCOVA

C. MANOVA

Bernard thinks some college students spend more money during the semester than others, and that this difference is related to the students' majors. He wants to compare the total amount of money spent at the end of one semester by American college students who major is psychology to that spent by history or physics majors. What is the second step Bernard should follow for testing his hypothesis? A. Identify population 1 as all psychology majors, population 2 as all history majors, and population 3 as all physics majors B. State the null hypothesis as college students majoring in psychology, history, or physics do not spend the same amount of money during one semester on average. State the research hypothesis as college students majoring in psychology spend about the same amount of money during one semester on average as do history and physics majors. C. State the null hypothesis as college students majoring in psychology, history, or physics spend about the same amount of money during one semester on average. State the research hypothesis as college students majoring in psychology, history, or physics do not spend the same amount of money during one semester on average. D. Use the F distribution with 2 and 45 degrees of freedom.

C. State the null hypothesis as college students majoring in psychology, history, or physics spend about the same amount of money during one semester on average. State the research hypothesis as college students majoring in psychology, history, or physics do not spend the same amount of money during one semester on average.

A researcher examines the effectiveness of different body lotions by having 12 participants apply four different lotions to the same, unique body locations daily for two weeks. For example, lotion #1 is always applied to the right thigh, while lotion #2 is applied to the upper right arm. The participants were randomly selected at a drugstore in a busy area. What is the null hypothesis for this study? A. Differences exist between the average effectiveness assessments of each lotion. B. Lotions cause differences in skin quality across locations. C. The effectiveness of the four different lotions is the same, on average. D. The lotions are the same in terms of effectiveness.

C. The effectiveness of the four different lotions is the same, on average.

Which of these is NOT an assumption of a two-way between-groups ANOVA? A. The underlying population distributions are normal. B. The variability in underlying populations is similar. C. The participants are matched on important characteristics. D. Participants are randomly selected.

C. The participants are matched on important characteristics.

A Tukey HSD is computed to compare two groups following an ANOVA that compared five groups. The within-groups degrees of freedom for the test are 7, and the computed HSD value is 6.24. What could be concluded about this analysis if evaluated at a p level of 0.05? A. The test statistic failed to exceed the cutoff, so there is no indication of a difference between these two groups. B. The test statistic exceeded the critical cutoff, indicating equality of these two groups. C. The test statistic is significant, revealing a statistical difference between the two groups. D. There is not enough information to make a conclusion.

C. The test statistic is significant, revealing a statistical difference between the two groups.

Does the F distribution take into account individual differences when comparing sample means? A. No; we should be careful not to generalize the results because the error of the F statistic is very large. B. No; that is why we should only rarely use the F distribution and instead run multiple t tests. C. Yes; as the variability within the individual samples decreases, the F statistic becomes larger since the distributions are not overlapping very much. D. Yes; as the variability within the individual samples decreases, the F statistic becomes smaller and less confident.

C. Yes; as the variability within the individual samples decreases, the F statistic becomes larger since the distributions are not overlapping very much.

For the three statistics F, z, and t, divide _____ variability by _____ variability to analyze the relation between variables. A. within-groups; between-groups B. within-groups; standard deviation C. between-groups; within-groups D. between-groups; random error

C. between-groups; within-groups

Although the hypothesis test can provide the probability that the levels of the independent variable lead to differences in the dependent variable, it is important to calculate effect size to: A. determine how many participants are needed to detect an effect. B. assess where the differences exist between conditions in the study. C. determine if the differences are large enough to matter. D. assess the probability of a Type II error.

C. determine if the differences are large enough to matter.

A main effect for a two-way ANOVA is the: A. research hypothesis of the study. B. influence of the dependent variable on one of the independent variables. C. influence of one of the independent variables on the dependent variable. D. main experimenter's bias as a confound to the study.

C. influence of one of the independent variables on the dependent variable.

Overall, children did not remember more words than adults on a memory test, F (1, 153) = 3.00, p > 0.10, and participants listening to music during the test did not remember more words than those not listening to music, F (1, 153) = 1.98, p > 0.10. However, listening to music significantly aided the children in remembering the words, while it hindered the adults in remembering the words, F (1, 153) = 12.73, p < 0.05. Which effect(s) must be present in this study for these results to be valid? A. main effect of age B. main effect of music C. interaction of age and music D. main effect of age, main effect of music, and interaction of age and music

C. interaction of age and music

Clara works for an advertising firm and needs to understand how an individual's levels of experience with cooking (novice, intermediate, or expert) affect how he or she will rate a new group of cookware advertisements. What type of design would be best for Clara to use? A. z test B. t test C. one-way between-groups ANOVA D. one-way within-groups ANOVA

C. one-way between-groups ANOVA

The National Collegiate Athletic Association (NCAA) cares about success for athletes both in their sports and in their education. A researcher hired by the NCAA wants to know how athletes' academic performance is affected by the stage of their competitive season. She examines performance in the preseason, throughout the active competitive season, and postseason, having 150 athletes, from across several different sports, assessed during each period. What statistical analysis would be appropriate for this research? A. one-way between-groups ANOVA B. paired-samples t tests C. one-way within-groups ANOVA D. independent-samples t tests

C. one-way within-groups ANOVA

The one-way within-groups ANOVA has an additional assumption compared to the between-groups ANOVA. Which assumption is unique to the within-groups ANOVA? A. random selection of participants B. the underlying population distributions are normal C. order effects are considered and controlled D. the assumption of homoscedasticity

C. order effects are considered and controlled

In a _____, the strength of the effect varies under certain conditions, but not the _____. A. hypothesis test; effect size B. effect size; z score C. quantitative interaction; direction D. qualitative interaction; F statistic

C. quantitative interaction; direction

When using a one-way within-groups ANOVA, the variability due to individual differences is _____, resulting in a _____ F statistic. A. reduced; smaller B. increased; smaller C. reduced; larger D. increased; larger

C. reduced; larger

A student researcher conducts a study that is analyzed using a two-way between-groups ANOVA. Unfortunately, none of the three F statistics were statistically significant. The student is confident that there is something to her research question, and she wonders if she simply didn't collect enough data to detect anything. She computes effect size measures and gets the following values: 0.012 for the first main effect, 0.073 for the second main effect, and 0.0017 for the interaction. If she were to conduct additional research, what would you recommend she pursue? A. the interaction because it has a strong effect size B. the first main effect because it has a small effect size C. the second main effect because it has a medium effect size D. the interaction because its significance would overshadow both main effects

C. the second main effect because it has a medium effect size

A researcher wants to examine the effect of drugs and diet on systolic blood pressure. She randomly assigns 20 individuals with high blood pressure to one of four treatments: control (no diet or drugs), diet modification only, drug only, drug and diet modification. What type of design is appropriate for this study? A. one-way within-groups ANOVA B. two-way within-groups ANOVA C. two-way between-groups ANOVA D. mixed-design ANOVA

C. two-way between-groups ANOVA

A researcher compares depression levels of people residing in five different climate regions. She collects data from 15 randomly selected people in each region. If she compares her groups using a between-groups, one-way ANOVA at a p level of 0.05, the critical value for her F statistic would be: A. 3.60. B. 3.29. C. 2.76. D. 2.50.

D. 2.50.

A researcher sets up a study to examine how lecture comprehension of college students is affected by lecture type (history, psychology, statistics, or English), classroom size (large or small), presentation method (blackboard, overhead projector, or computer), and instructor (graduate student, assistant professor, or full professor). How is the design described? A. 1 × 1 × 1 × 1 within-groups ANOVA B. 4 × 1 between-groups ANOVA C. 4 × 2 × 3 × 3 within-groups ANOVA D. 4 × 2 × 3 × 3 between-groups ANOVA

D. 4 × 2 × 3 × 3 between-groups ANOVA

A researcher sets up a study to examine how lecture comprehension of college students is affected by lecture type (history, psychology, statistics, or English), classroom size (large or small), presentation method (blackboard, overhead projector, or computer), and instructor (graduate student, assistant professor, or full professor). How many cells are in this design? A. 4 B. 12 C. 24 D. 72

D. 72

Tilbe wants to compare young children's verbal test scores across three experimental conditions (different levels of instruction from low to high) and one control group (no instruction). What type of test should she use? A. z test B. t test C. Bonferroni test D. ANOVA

D. ANOVA

Henry is examining the effectiveness of using scare tactics to manipulate the behaviors of people living on the same island but in different regions, categorized as the beach, the valley, and the mountains. What is the first step Henry should follow for hypothesis testing? A. Identify population 1 as all beach inhabitants on the island, population 2 as all valley inhabitants on the island, and population 3 as all mountain inhabitants on the island. He should also use a t distribution to make comparisons employing a paired-samples t test. B. State the null hypothesis—there is no difference between locations on the effectiveness of scare tactics in manipulating behavior—and the research hypothesis—at least one group of island inhabitants will exhibit different behaviors as a result of the scare tactics. C. Use the F distribution with 2 and 51 degrees of freedom. D. Identify population 1 as all beach inhabitants on the island, population 2 as all valley inhabitants on the island, and population 3 as all mountain inhabitants on the island. He should also use an F distribution with a one-way between-groups ANOVA.

D. Identify population 1 as all beach inhabitants on the island, population 2 as all valley inhabitants on the island, and population 3 as all mountain inhabitants on the island. He should also use an F distribution with a one-way between-groups ANOVA.

Mike wants to test how different levels of verbal ability and math ability influence a measure of reading comprehension and a measure of graph interpretation. He is concerned that IQ may confound the results since it is likely to have an effect, too. What test should he use to account for this third variable? A. factorial ANOVA B. MANOVA C. ANCOVA D. MANCOVA

D. MANCOVA

When performing a two-way between-groups ANOVA, effect size is measured using _____, and it is calculated for _____ effects. A. Cohen's d; two B. R2; two C. Cohen's d; three D. R2; three

D. R2; three

Ana is comparing spatial ability scores for four groups. She finds that the F statistic for her test is 4.01, and the cutoff value she identified prior to her analysis was 3.45. Should Ana reject or fail to reject the null hypothesis and what, if any, other steps does she need to take? A. Fail to reject the null hypothesis since her F statistic is below the cutoff, and perform a post hoc test to determine between which groups the significant difference lies. B. Fail to reject the null hypothesis since her F statistic is below the cutoff, and write up the results with no further testing. C. Reject the null hypothesis since her F statistic is beyond the cutoff, and write up the results with no further testing. D. Reject the null hypothesis since her F statistic is beyond the cutoff, and perform a post hoc test to determine between which groups the significant difference occurs.

D. Reject the null hypothesis since her F statistic is beyond the cutoff, and perform a post hoc test to determine between which groups the significant difference occurs.

Which symbol is NOT a type of sum of squares (SS) listed in a source table? A. SSbetween B. SStotal C. SSwithin D. SSdegrees of freedom

D. SSdegrees of freedom

A bar graph displays the mean scores on a test of mental rotation for students majoring in psychology or chemistry who have either high or low spatial abilities. Psychology and chemistry students with low spatial skills scored about 35 percent correct on the mental rotation test, while psychology and chemistry students with high spatial skills scored about 70 percent correct. What can be inferred from these data? A. There is an interaction between spatial ability and college major. B. There appears to be a main effect of mental rotation only. C. There appears to be a main effect of college major only. D. There appears to be a main effect of spatial ability only.

D. There appears to be a main effect of spatial ability only.

A researcher fails to reject the null hypothesis after using an F table to determine the significance value. What can be concluded? A. There is a difference between means that we expected just by chance. B. There is a difference between means that is larger than we would predict by chance. C. There is no difference between means, which is what we would expect by chance. D. There is no difference between means.

D. There is no difference between means.

When using a one-way within-groups ANOVA, the variability due to individual differences in reduced resulting in a ____ F statistic, making it ____ to reject the null hypothesis. A. larger; harder B. smaller; easier C. smaller; harder D. larger; easier

D. larger; easier

Overall, rats that received a drug took longer to find their way out of a maze than rats that received a placebo, F (1, 57) = 7.23, p < 0.05; the drug had a large effect on albino rats and virtually no effect on wild-bred rats, F (1, 57) = 11.01, p < 0.05. However, there was no overall difference in the time of albino rats compared to that of wild-bred rats, F (1, 57) = 1.11, p > 0.10. Which effect(s) must be present for these results to be true? A. main effect of drug B. main effect of rat species C. interaction of drug and rat species D. main effect of drug and an interaction of drug and rat species

D. main effect of drug and an interaction of drug and rat species

In determining main effects and interactions in a factorial ANOVA, it is helpful to use the _____ in a table of means. A. line of best fit B. standard error C. individual scores D. marginal means

D. marginal means

A researcher for Major League Baseball is interested in visual accuracy of the players. The indicators of visual accuracy are batting average (high vs. low) and a computer "flicker" program that indicates changes in either the central or the noncentral region of a scene. The dependent variable is the time it takes to notice a change during flickers. When the researcher looks at a table of means, the data show that central flicker and high batting average = 40; noncentral flicker and high batting average = 20; central flicker and low batting average = 20; and noncentral flicker and low batting average = 40. Assuming a very powerful statistical test, the researcher should find: A. a main effect for "flicker" type. B. a main effect for batting average. C. no main effects and no interaction. D. no main effects but a significant interaction.

D. no main effects but a significant interaction.

When conducting a Bonferroni test, we divide the overall p level by the: A. F statistic. B. critical F value. C. total number of participants. D. number of comparisons.

D. number of comparisons.

The one-way within-groups ANOVA is used when there are: A. two independent variables that all participants experience and at least two dependent measures. B. a scale independent variable with multiple levels that all participants experience. C. two or more ordinal variables with multiple levels and a scale dependent variable. D. one nominal or ordinal independent variable with more than two levels, a scale-dependent variable, and every participant is in every group.

D. one nominal or ordinal independent variable with more than two levels, a scale-dependent variable, and every participant is in every group.

In a _____, the effect of one independent variable reverses based on the _____. A. hypothesis test; effect size B. quantitative interaction; level of the other independent variable C. quantitative interaction; direction of the difference D. qualitative interaction; level of the other independent variable

D. qualitative interaction; level of the other independent variable

The one-way within-groups ANOVA has a new source of variability, known as the subjects sum of squares. To calculate this sum of squares, subtract: A. each participant's scores from the mean and sum the differences. B. the grand mean from the mean of each cell. C. the sum of squares within from the sum of squares total. D. the grand mean from each participant's mean for all of his or her scores.

D. the grand mean from each participant's mean for all of his or her scores.

When it is not possible to have participants experience all levels of the independent variable, an alternative approach to a within-groups design can be used. This approach offers the same advantage in statistical power as the within-groups design by: A. creating larger between-groups differences by using more extreme levels of the independent variable. B. using a larger number of participants across conditions. C. assessing differences with planned comparisons rather than post hoc tests. D. using participants in each group that are matched on variables of interest that we want to control across conditions.

D. using participants in each group that are matched on variables of interest that we want to control across conditions.