Exam 1

1. Metainformation

   Tag	Value
   file	Inferential_Statistics_vufsw-mixed_design_anova-1062-en_vufsw-mixed_design_anova-1062-en
   name	vufsw-mixed design anova-1062-en
   section	inferential statistics/parametric techniques/anova/mixed design anova
   type	schoice
   solution	TRUE, FALSE, FALSE, FALSE
   Type	interpreting out
   Program	NA
   Language	English
   Level	statistical thinking

   Question

   An experiment was done to compare the effect of having a conversation via a hands-free mobile phone, having a conversation with an in-car passenger, and no distraction (baseline) on driving accuracy. Twenty participants from two different age groups (18–25 years and 26–40 years) took part. All participants in both age groups took part in all three conditions of the experiment (in counterbalanced order), and their driving accuracy was measured by a layperson who remained unaware of the experimental hypothesis. Which of the following sentences is the correct interpretation of the main effect of distraction?

   

   
   
   1. TRUE: The main effect of distraction is significant,  F (2, 36) = 45.95,  p < .001. This effect tells us that average ratings of driving accuracy differed across the three types of distraction.
   2. FALSE: The main effect of distraction is significant, F(1.681, 30.257) = 45.95, p  <  .001. This effect tells us that average ratings of driving accuracy differed across the three types of distraction.
   3. FALSE: The age of the driver significantly interacted with the type of distraction,  F(2, 36) = 45.95, p < .001. This effect tells us that average ratings of driving accuracy across the different types of distraction were different in the two age groups.
   4. FALSE: It is not possible to interpret the main effect of distraction because the assumption of sphericity is violated.
   
   

   Solution

   Mauchly’s test for sphericity shows that the assumption of sphericity is not violated. Therefore, we look at the row ’Sphericity assumed“. The question is about the main effect, so we look at the first panel of the table. The F-value is F (2, 36) = 45.95 and the p-value is .000. Therefore, the option” The main effect of distraction is significant,  F (2, 36) = 45.95,  p  = .00. This effect tells us that the profile of ratings of driving accuracy differed across the three types of distraction" is correct.

   Language
   English & Nederlands

   M&T Mixed design ANOVA
   Default value

   M&T MVA
   Standaardwaarde

   
   
   1. True
   2. False
   3. False
   4. False