PSYCH STATS TEST #3

a researcher computes a 3x4 between subjects ANOVA. What are the degrees of freedom for Factor A for this study

2

A researcher compared difference 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 significant ANOVA indicates that all pairs of groups means significant differ

FALSE

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

FALSE

when we arrange the data in an ANOVA test in a table, the number of cells represents the number of (BLANK) in a study

groups

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

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

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 observed the levels of two factors

The one way between subjects ANOVA is used when different participants are assigned to (BLANK) groups

two or more

Mean square error MSe is another name for mean square within MSw

TRUE

Which measures of proportion of variance is the most conservative estimate

omega-squared

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

20

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 for error for the one way between subjects ANOVA

27

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

4.30

a researcher computes the following 2x3 between subjects ANOVA in which 11 participants were observed in each group. Which effect was significant at a .05 level of significant using the two way between subjects ANOVA Source of Variation SS df MS F Factor A 10 Factor B AXB 40 Error 240 Total 340

Factor B and AxB interaction

Without changing the value of error variance, the (BLANK) the between groups variability, the more likely we are to reject the null hypothesis

larger

Using an A*B ANVA, 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 were observed in the same statistical design

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

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

within-group variation and error variation

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 significant

4.17

A researcher computes the following one way between subjects ANOVA table. State the decision at a .05 Source of Variation SS DF MS F Between Groups 32 4 Within groups (error) 45 total 122

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 .05 level of significance. (hint complete the table first) Source of Variation SS df MS F Between groups 120 Within groups (error) Total 780

there is not enough information to answer this question

one-way between subjects ANOVA

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

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 an equal to mean square error

In a two war between subjects ANOVA, which effect is potentially the most informative when it i significant

the interaction

Homogeneity of variance refers to the assumption that:

the variation of scores in each population is equal

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 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 3x5 between subjects ANOVA. What are the degrees of freedom for the AxB interaction for this study

8

Using a two way between subjects Anova with factor A(Gender: male, female) and Factor B(type of emplyment: blue collar, white collar), a researcher found that scores for men and women significantly varied across the levels of the second factor 9type of employment) In this study, the researcher found a significant

A*B interaction

A research computes two 2x2 between subjects ANOVAs. In study 1 he observes 8 participants in each cell; in study 2 he observed12 participants in each cell. Which study is associated with a larger value for degrees of freedom for the AxB interaction?

Both studies have the same degrees of freedom for the AxB interaction

What 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,parent,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

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 significant? (HINT you have been given SS, not MS)

retain the null

A researcher computes a 2x3 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 xB interaction test, then the decision for each test

will be significant for both main effects and the AXB interaction

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 3 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

.5

A researcher computes a 2X3 factorial ANOVA. In this example, how many interactions can be observed

1

There are (BLANK) cells or groups in a 3*4 ANOVA design

12

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* B interaction

2

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 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 official value for the one-way between subjects ANOVA at a .05 level significance

3.47

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

A researcher randomly measures social adjustment among children from different family backgrounds 0levels of factor A: divorced, married, single)who engaged in one of five social activities (factor B0. 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 researcher conducts two studies. In study 1 n= 8, p=2 and q=2. In study 2, n=8, p-3, q=2. If Fobt=406 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