Stats

There are ____ cells or groups in a 3 × 4 ANOVA design.

12

In a two-way between-subjects ANOVA, which effect is potentially the most informative when it is significant?

the interaction

The source of variation that cannot be attributed to or caused by having different groups is called:

within-groups variation or error variation

A researcher computes a 2 × 3 between-subjects ANOVA test in which 11 participants were observed in each condition. If F = 5.17 for both main effect tests and the A × B interaction test, then the decision for each test

will be significant for both main effects and the A × B interaction

A researcher randomly measures social adjustment among children from different family backgrounds (levels of Factor A: divorced, married, single) who engaged in one of five social activities (Factor B). For this study, 10 children were observed in each group. If SSA = 10, MSB = 12, SSAB = 48, and SSW = 405, then which effect was significant at a .05 level using the two-way between-subjects ANOVA? (Hint: If the F-table doesn't include the dfW you're looking for, use dfW = 120.)

Factor B (social activities)

A statistical procedure used to test hypotheses for one factor with two or more levels concerning the variance among group means, where different participants are observed at each level of a factor, is called the

one-way between-subjects ANOVA

Hypothesis tests used to analyze a significant interaction by comparing the mean differences of one factor at each level of a second factor are called:

simple main effect tests

When the variability attributed to between-groups is equal to the variability attributed to error, then the value of the test statistic for a one-way between-subjects ANOVA is,

Equal to 1.

Without changing the value of error variance, the ________ the between-groups variability, the more likely we are to reject the null hypothesis.

larger

A researcher randomly assigned 16 rodents to experience one of four levels of shock (n = 4 per group) following the illumination of a visual cue. If SSB = 24 and SSW = 48, then what was the decision at a .05 level of significance for a one-way between-subjects ANOVA? (Hint: What is the relationship between SS and MS?)

Retain the null hypothesis.

A researcher computes a 3 × 4 between-subjects ANOVA. What are the degrees of freedom for Factor A for this study?

2

In a study with four groups and 10 participants in each group, the sum of squares for the between-groups source of variation is 60. What is the value for the mean square between-groups in this study?

20

Using a two-way between-subjects ANOVA with Factor A (Gender: male, female) and Factor B (Type of employment: blue collar, white collar), a researcher found that scores for men and women significantly varied across the levels of the second factor (type of employment). In this study, the researcher found a significant

A × B interaction

A significant ANOVA indicates that all pairs of group means significant differ

FALSE

Mean square error (MSE) is another name for mean square within (MSW).

True

When we arrange the data in an ANOVA test in a table, the number of cells represents the number of ________ in a study.

groups

Homogeneity of variance refers to the assumption that

the variance of scores in each population is equal

A researcher computes a 2 × 3 factorial ANOVA. In this example, how many interactions can be observed?

1

A researcher reports that alertness in the classroom varies by the intensity of lighting in the room, F(3, 36) = 3.96, p < .05. How many light intensity groups were observed in this study?

4

A researcher computes a 3 × 5 between-subjects ANOVA. What are the degrees of freedom for the A × B interaction for this study?

8

A researcher computes two 2 × 2 between-subjects ANOVAs. In Study 1, he observes 8 participants in each cell; in Study 2, he observes 12 participants in each cell. Which study is associated with a larger value for degrees of freedom for the A × B interaction?

Both studies have the same degrees of freedom for the A × B interaction.

Which measure of proportion of variance is the most conservative estimate

omega-squared

A researcher compares differences in positivity between participants in a low-, middle-, or upper-middle-class family. If she observes 15 participants in each group, then what are the degrees of freedom for the one-way between-subjects ANOVA?

(2, 42)

A researcher conducts a study using the one-way between-subjects ANOVA. She computes SSB = 180 and SSW = 520. What is the effect size for this test using eta-squared?

.26

In a study with three groups and 13 participants in each group, the sum of squares for the within-groups source of variation is 18. What is the value for the mean square within-groups in this study?

0.5

A researcher conducts a study in which 12 participants are observed at each combination of two factors, where Factor A has three levels and Factor B has two levels. What are the degrees of freedom for the A x B interaction?

2

A researcher conducts a study in which k = 6 and n = 6 per group. What are the critical values for the one-way between-subjects ANOVA at a .05 level of significance?

2.53

A researcher measures attractiveness ratings of a male confederate among 30 women who were told the confederate was either single, dating, or married (n = 10 per group). What are the degrees of freedom for error for the one-way between-subjects ANOVA?

27

What are the degrees of freedom numerator for a study with n = 12 in each of four groups?

3

Which of the following statements is the appropriate way to read the degrees of freedom for an ANOVA with 10 participants in each of four groups?

3 and 36 degrees of freedom

A researcher assigned participants (n = 8 per group) to read vignettes describing a person engaging in either a helpful, hurtful, or neutral act. Different participants were assigned to each group and asked to rate how positively they viewed the person described in the vignette. What is the critical value for the one-way between-subjects ANOVA at a .05 level of significance?

3.47

Not including the total variation, how many sources of variation are measured in a two-way between-subjects ANOVA? (Include all types of between-group variation.)

4

A researcher conducts a study in which six participants are observed at each combination of two factors, where Factor A has two levels and Factor B has three levels. What is the critical value for the main effect test of Factor A using a .05 level of significance?

4.17

What is the critical value for a study with n = 12 in each of two groups at a .05 level of significance?

4.30

If each main effect is significant, then the interaction must also be significant for a two-way between-subjects ANOVA.

False

Which post hoc test is associated with the greatest power to detect an effect?

Fisher's LSD test

A researcher randomly assigned 32 children to observe a short clip depicting either their favorite superhero, a parent, a teacher, or no person at all (n = 8 per group). If SSB = 30 and SSW = 104, then what was the decision at a .05 level of significance for a one-way between-subjects ANOVA? (Hint: What is the relationship between SS and MS?)

Retain the null hypothesis.

A researcher conducts two studies. In Study 1, n = 8, p = 2, and q = 2. In Study 2, n = 8, p = 3, and q = 2. If Fobt = 4.06 for the interaction in both studies, then in which study will the decision be to reject the null hypothesis for the interaction test at a .05 level of significance?

Study 2

A source of variation associated with the variance of group means across the combination of levels of two factors is called a(n):

interaction

The denominator of the test statistic for the main effects and interaction in a two-way between-subjects ANOVA

is equal to mean square error

Using an A × B ANOVA, a researcher concludes that Factor A is significant, independent of Factor B. In this study, this researcher found a significant

main effect of Factor A

Which of the following hypotheses identifies a prediction that requires that two factors we observed in the same statistical design?

mood will improve most when people consume foods that are high in sugar and high in fat

Using a two-way between-subjects ANOVA, Factor A has two levels, Factor B has two levels, and n = 12 per group. If SSAB = 15 and SSW = 220, then what was the decision for the interaction test at a .05 level of significance? (Hint: You have been given SS, not MS.)

retain the null

A researcher computes a two-way between-subjects ANOVA and finds a significant A × B interaction and two main effects. Which significant effect should be analyzed first?

the significant interaction

To report the results of the one-way between-subjects ANOVA, which of the following is reported?

the test statistic, the p value, the degrees of freedom numerator and denominator

The two-way ANOVA differs from the one-way ANOVA in that

the two-way ANOVA is used when we observe the levels of two factors

The one-way between-subjects ANOVA is used when different participants are assigned to ________ group(s)

two or more