Deck 16: Glm 5: Mixed Designs

Question 1

Examine the within-group effects table. Which conditions were significant?

A) Shoe
B) Shoe × platform
C) Platform*
D) Gender × shoe × platform

Answer 1

Shoe

Question 2

Suppose you wished to investigate the force exerted on a force platform between men and women with three different types of footwear (barefoot, no cushioning, basic neutral shoe, BC; and complex cushioned neutral shoe, CCS). If you wished to compare the force exerted when running barefoot with the BC shoe and then the CCS shoe, what type of contrast might be appropriate?

A) Simple
B) Repeated
C) Helmert
D) Deviation

Answer 2

Simple

Question 3

Which variable would be considered the between-groups variable?

A) Running status
B) Concentration
C) Flavoured water (placebo)
D) 9% solution (high dose)

Answer 3

Running status

Question 4

How many levels were measured on the running status variable?

A) 2
B) 3
C) 4

Question 5

If specific hypotheses to particular research questions are required, which of the following would be most appropriate?

A) Contrasts
B) Post hoc tests
C) Multiple t-tests
D) The ANOVA result alone is sufficient.

Question 6

If you were investigating mental alertness when exposed to prolonged periods of sleep deprivation, what would be the most appropriate contrast to use if you were interested in the reduction in alertness from hour to hour (e.g. 1 vs. 2 h, 2 vs. 3 h, 3 vs. 4 h, etc.)?

A) Repeated
B) Simple
C) Helmert
D) Deviation

Question 7

What do the between-group effects tell us about the gender variable?

A) There is no significant difference between male and female participants.
B) There is a significant difference between male and female participants.
C) There is significant difference between male and female participants when associated with the platform variable.
D) The results were marginally non-significant.

Question 8

The platform × gender interaction produced the following result: F_(1,14) = .395, p = .54, = .027. Which of the following descriptions best describes the result?

A) There was no significant interaction between the platform and gender variables and the effect size was weak.
B) There was a significant interaction between the platform and gender variables, but the effect size was weak.
C) There was no significant interaction between the platform and gender variables but the effect size was strong.
D) There was a significant interaction between the platform and gender variables and the effect size was strong.

Question 9

Analyse the SPSS file by running a mixed design ANOVA with a simple contrast for all three independent variables. You should see the following table. Why is there not a Mauchley's test significance value for the platform variable (i.e. whether the participants could see the force platform or not)?

A) There are only two levels for this variable.
B) The data were not normally distributed.
C) Levene's test was significant.
D) The Kolmogorov-Smirnov test was not significant.

Question 10

If you wanted to run a simple contrast on the force exerted when running over a force platform and you used the barefoot trial as control, where would it be best to position it in the SPSS data editor?

A) As the first data set
B) As the second data set
C) As the third data set
D) As the first or third data set

Question 11

What does the within-groups table refer to?

A) Repeated-measures effects only
B) Interaction effects only
C) Repeated-measures and interaction effects
D) Between group effects

Question 12

Which variable would be considered the within-groups variable?

A) Running status
B) Concentration
C) Flavoured water (placebo)
D) 9% solution (high dose)

Question 13

A mixed design ANOVA is based on which type of model?

A) Linear
B) Binomial
C) Syntax
D) Asymmetrical

Question 14

When running a mixed design ANOVA for a particular experiment a significant Levene's test is found. What is the most likely cause?

A) Outlying data points / observations
B) Similar variance between the data sets
C) Data are normally distributed
D) Sphericity cannot be assumed

Question 15

If you were to introduce an additional variable called 'force platform status' which denoted whether the force platform was visible to the participants or not, how many experimental conditions would there be?

A) 5
B) 7
C) 9
D) 11

Question 16

If one or more of the conditions was significant, what would be the next appropriate step?

A) Transform the data to stabilize the variance between the groups.
B) No action is required as a mixed design ANOVA is stable enough to withstand a heterogeneous result.
C) A non-parametric equivalent to a mixed design ANOVA is required.
D) None of the above actions are appropriate.

Question 17

Analyse the following output box. What can be deduced from the results of Levene's test?

A) All the values are significant.
B) All the values are not significant.
C) With the exception of the barefoot unseen condition, all the values are significant.
D) With the exception of the barefoot unseen condition, all the values are not significant.

Question 18

What can be deduced about the sphericity of the shoe and shoe × platform variables?

A) Both variables are non-significant, and therefore sphericity can be assumed.
B) Both variables are significant, and therefore sphericity can be assumed.
C) Both variables are non-significant, and therefore sphericity cannot be assumed.
D) Both variables are significant, and therefore sphericity cannot be assumed.

Question 19

A simple contrast was performed between the barefoot (BF) strike and the basic sole (BS) strike and barefoot strike with the cushioned sole (CS) strike. The results were as follows, but how would you interpret them? F_(1,14) = 98.28, p < .001, = .88 (BS vs. BF)
F_(1,14) = 141.13, p < .001, = .91 (CS vs. BF)

A) Both the BS and CS conditions yielded significantly lower force strikes when compared with the BF condition.
B) Both the BS and CS conditions yielded significantly higher force strikes when compared with the BF condition.
C) The results between the three conditions were not significantly different.
D) The CS condition yielded significantly lower force strikes when compared with the BF condition, but the BS produced a significantly greater force strike than the BF condition.

Question 20

Ten experienced and ten novice distance runners (running status) were asked to run four marathons. During each run, a different carbohydrate solution (concentration) was consumed (flavoured water, placebo; 3% solution, low dose; 6% solution, medium dose; 9% solution, high dose) and race time was recorded. How many independent variables were measured?

A) 2
B) 3
C) 4
D) 5

Question 21

Overall, how would you summarize the data presented in this example?

A) The more cushioning in the shoe, the greater the reduction in force exerted, which was reduced further when the participants were not aware of the force platform position.
B) The more cushioning in the shoe, the greater the reduction in force exerted, which was reduced further when the participants were aware of the force platform position.
C) The less cushioning in the shoe, the greater the reduction in force exerted, which was reduced further when the participants were not aware of the force platform position.
D) The less cushioning in the shoe, the greater the reduction in force exerted, which was reduced further when the participants were aware of the force platform position.

Question 22

Calculate the r-value (effect size) for the platform variable contrast assuming that F(1,df_R) = 57.1 and df_R = 14.

A) .8
B) 15
C) 1.2
D) 1.0

Question 23

The following table refers to the results from the Bonferroni post hoc tests that were performed on the three shoe conditions (1 = barefoot, 2 = basic neutral shoe and 3 = complex neutral shoe). What does this post hoc test table contribute to our understanding of the results that the contrast did not?

A) Whether a significant difference exists between the BS and the CS conditions.
B) The post hoc test table does not contribute anything to our understanding as the contrast is more specific.
C) The post hoc test explains the same concepts as the contrast but is more accurate.
D) A homogeneity of variance result is provided.