Basic Statistics Behavioral Science Ch 12, 13, 14

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

1

How many sources of error are present in a one-way within-subjects ANOVA?

2

What is the minimum number of groups that can be observed using the one-way between-subjects ANOVA design?

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

A researcher computes a one-way within-subjects ANOVA using a sample of 8 participants. If the degrees of freedom error is 14, then how many groups were included in this study?

3

A researcher groups college students in a study based on their year in college (freshman, sophomore, junior, senior) and the type of college they attend (junior, technical, university). He concludes that perceptions of academic cheating are more positive among freshman attending junior college. To reach this conclusion, which statistical test would need to be computed?

All of these: a two-way between-subjects ANOVA, a simple main effect test, a post hoc test

A researcher computes a one-way within-subjects ANOVA, thus

All of these: the same participants were observed in each group, at least two groups were observed in the study, a repeated measures design was likely used

Which of the following post hoc tests uses the t-critical value in the calculation to determine the critical value for the test?

Fisher's LSD test

Which of the following is an assumption for computing a one-way within-subjects ANOVA?

Independent observations were made within groups, but not between groups.

Based on the data given below, which study is associated with the most consistent participant responding between groups? Study 1 Reward Size Person Small Medium Large A 2 3 4 B 1 2 3 C 3 4 5 D 0 2 4 Mean= 1.5 2.8 4.0 Study 2 Reward Size Person Small Medium Large A 2 2 4 B 3 3 3 C 1 4 4 D 0 2 5 Mean= 1.5 2.8 4.0

Study 1

To compute partial h2, it is necessary to

The answer is not: valueable.

A professor compared differences in class grades between students in their freshman, sophomore, junior, and senior years of college. If different participants were in each group, then what type of statistical design is appropriate for this study?

a one-way between-subjects ANOVA

A simple main effect test is appropriate for analyzing which significant result?

a significant interaction

An estimate of effect size with the two-way ANOVA is typically reported for

a significant main effect test and a significant interaction test

A researcher measures differences in recall between participants watching a regular or a 3-D movie clip with a romance, drama, or action theme. Different participants were observed in each group. What type of statistical design is appropriate for this study?

a two-way between-subjects ANOVA

The Bonferroni procedure is well adapted for which of the following research designs in which the same participants are observed in each group?

a within-subjects design

Post hoc tests are computed

following a significant ANOVA test to make pairwise comparisons

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

larger

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

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

Using a within-subjects ANOVA design,

n participants are observed k times

A researcher computes the following one-way between-subjects ANOVA table. State the decision at a .05 level of significance. (Hint: Complete the table first.) Source of Variation SS df MS F Between groups 32 4 Within groups (error) 45 Total 122

reject the null hypothesis

A researcher conducts a 2 ´ 4 between-subjects ANOVA in which 12 participants were observed in each group. If SSB = 18 and SSE = 264 for this study, then what is the decision for Factor B at a .05 level of significance?

reject the null hypothesis

A researcher has 18 participants rate the morality of a person described in a vignette as being registered as a Democrat, Republican, or Independent. If Fobt= 3.41 for a one-way within-subjects ANOVA, then what was the decision at a .05 level of significance?

reject the null hypothesis

A researcher assigns 21 adolescents to rate the likability of a person described in a vignette as having one of three personality traits. An equal number of participants are assigned to each group. If Fobt = 4.08 for this study, then what was

reject the null hypothesis.

A researcher computes the following one-way between-subjects ANOVA table for a study where k = 3 and n = 12. State the decision at a .05 level of significance. (Hint: Complete the table first.) Source of Variation SS df MS F Between groups 120 Within groups (error) Total 780

retain the null hypothesis

A researcher computes the following one-way within-subjects ANOVA table. State the decision at a .05 level of significance. Source of Variation SS df MS Fobt Between groups 30 Between persons 9 Within groups (error) 9 6 Total 19

retain the null hypothesis

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 SSBG = 30 and SSE = 104, then what was the decision at a .05 level of significance for a one-way between-subjects ANOVA?

retain the null hypothesis.

Partial estimates of effect size make the denominator ______ because the between-persons variability is removed.

smaller

For the effects of a two-way between-subjects ANOVA, which values must be known to compute effect size using h2?

sum of squares

A researcher conducts two studies. In Study 1, she recorded the amount consumed (in calories) among eight participants observed at three meal times (breakfast, lunch, and dinner). In Study 2, she conducted the same study, except that n = 12 participants observed at each of three meal times. Which study is associated with a larger value for degrees of freedom between groups for a one-way within-subjects ANOVA?

the degrees of freedom between groups are the same in each study

The following results is reported for a one-way within-subjects ANOVA: F(2, 27) = 3.55, p < .05 ( = -.14). Which value in the summary cannot be correct?

the effect size

A lowercase k is used to denote ______ using a one-way ANOVA.

the number of groups in a study and the number of levels of the factor in a study

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

the significant interaction

A researcher computes a two-way between-subjects ANOVA and finds a significant main effect of Factor A and an A ´ B interaction. Which significant effect should typically be analyzed first?

the significant interaction

A professor compares the exam grades of students based on whether they have a learning disability (yes, no) and where they sit in the classroom (in the front, middle, or back row). Different participants were observed in each group. What type of statistical design is appropriate for this study?

two-way between-subjects ANOVA

A researcher computes a 2 ´ 3 between-subjects ANOVA test in which 11 participants were observed in each condition. If F = 5.20 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

The source of variability associated with error variance in the one-way between-subjects ANOVA is called

within-groups variability

Which of the following designs are associated with greater power to detect an effect, particularly when there is consistent participant responding between groups?

within-subjects design

A researcher conducts a study using the one-way between-subjects ANOVA. He computes SSBG = 120 and SSE = 200. What is the effect size for this test using h2?

.38

There are ______ cells or groups in a 3 ´ 4 ANOVA design.

12

A researcher computes a one-way within-subjects ANOVA for a study in which participants are observed across five groups. If the degrees of freedom error is 56, then how many participants were observed in this study?

15

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

A researcher computes a 2 ´ 3 between-subjects ANOVA in which six participants are observed in each cell. What are the degrees of freedom error for this study?

30

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

8

How does w2 for the one-way between-subjects ANOVA correct for the fact that h2 tends to be a biased estimate of effect size?

All of these: It corrects for the size of error by including MSE in the formula., It includes the degrees of freedom between groups (dfBG) in the formula., It accounts for the number of groups that were observed.

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, SSAXB = 48, and SSE = 405, then which effect was significant at a .05 level using the two-way between-subjects ANOVA? Question 9 options:

Factor B (social activities)

Which of the following post hoc tests is associated with the greatest power to detect an effect?

Fisher's LSD test

A researcher conducts two studies using the two-way between-subjects ANOVA. The sum of squares total is smaller in Study 1 than in Study 2; the sum of squares for Factor A is the same in both studies. In which study will the effect size be larger for Factor A using w2

Study 1

The complexity of the two-way ANOVA differs from that of the t tests and the one-way ANOVAs in that,

all of these: *two factors can be observed using the two-way ANOVA, but not using the t tests and the one-way ANOVAs *an interaction can be observed using the two-way ANOVA, but not using the t tests and the one-way ANOVAs *three hypothesis are made with one statistical test using the two-way ANOVA, but not using the t tests and the one-way ANOVAs

ANOVA stands for

analysis of variance

A researcher notes that the variability attributed to difference between group means is quite large. Which source of variation is the researcher referring to?

between groups

The source of variation that is associated with differences between groups in a study is called

between-groups variability

A researcher computes a 4 ´ 4 between-subjects ANOVA and finds two significant main effects and a significant interaction. What is typically the next appropriate step?

compute simple main effect tests for the interaction

The term "within-subjects" refers to

observing the same participants in each group

"Within subjects" is also called

repeated measures

The alpha level for each hypothesis test made on the same set of data is called

testwise alpha

The following results is reported for a one-way within-subjects ANOVA: F(2, 27) = 3.20, p < .05 ( = .14). Which value in the summary suggests that the design was within subjects?

the partial estimate for h2