+ Reply to Thread
Results 1 to 4 of 4

Thread: Advice requested about mixed ANOVA

  1. #1
    Points: 11, Level: 1
    Level completed: 21%, Points required for next Level: 39

    Posts
    2
    Thanks
    1
    Thanked 0 Times in 0 Posts

    Need your help with an Anova analysis




    Hi

    I'm studying the effect of different music styles on performance tasks.
    I'm considering a mixed ANOVA analysis, but I'm not very confident about my stats skills and I'd be very happy to receive good advices from the experts here.

    Subjects are split (randomly) in 3 groups, based on the music style of a song (that they listen, in the experimental condition). So this condition (3 modalities : MS1, MS2, MS3) would be my between-subjects factor.

    Performance is measured before and after listening to the track. Its the same performance task for all subjects. So Time (2 measures : T0, T1) would be my within-subjects factor.

    Now this is what I'd like to test :

    - Is there a performance improvement between T0 & T1, depending on the music style.

    but more importantly :

    - Is there a significant difference in the improvement between T0 & T1 depending on the music style.

    In other words, is there less improvement between T0 & T1 for the performance in MS1 condition compared to the other conditions for example.

    For this last one, a mixed ANOVA is especially required I guess, but I'm not sure about the way to deal with the less/more improvement aspect. Should I use the contrast or post-hoc for example ?

    Thank you very much for any input.
    Last edited by sconnar; 01-18-2017 at 08:11 AM.

  2. #2
    Points: 1,974, Level: 26
    Level completed: 74%, Points required for next Level: 26

    Location
    New Zealand
    Posts
    227
    Thanks
    3
    Thanked 48 Times in 47 Posts

    Re: Need your help with an Anova analysis

    If you are interested mainly in the question of whether or not the three groups show different improvements, you would be looking for a significant Time/Modality interaction, Interactions with more than two groups are hard to interpret and explain.
    An alternative, and mathematically equivalent, is to find the before/after difference for each subject and do a one way anova on the differences. Easier to do, interpret and explain.

  3. The Following User Says Thank You to katxt For This Useful Post:

    sconnar (01-19-2017)

  4. #3
    Points: 11, Level: 1
    Level completed: 21%, Points required for next Level: 39

    Posts
    2
    Thanks
    1
    Thanked 0 Times in 0 Posts

    Re: Need your help with an Anova analysis

    Quote Originally Posted by katxt View Post
    If you are interested mainly in the question of whether or not the three groups show different improvements, you would be looking for a significant Time/Modality interaction, Interactions with more than two groups are hard to interpret and explain.
    An alternative, and mathematically equivalent, is to find the before/after difference for each subject and do a one way anova on the differences. Easier to do, interpret and explain.
    Hello Katxt.

    If I create a before / after data for each subject (I guess that it would be " value of performance at T1" minus "value performance at T0") then I could indeed do a one way anova with that. If I understand correctly, then it should be a "between-subject" anova, right ?
    Its smart, indeed. Thank you very much!

  5. #4
    Points: 1,974, Level: 26
    Level completed: 74%, Points required for next Level: 26

    Location
    New Zealand
    Posts
    227
    Thanks
    3
    Thanked 48 Times in 47 Posts

    Re: Need your help with an Anova analysis


    That's right. A one way anova is always between subjects. Many stats programs also give you a p value for the constant (the average value). This would answer your first question about whether there was a time difference overall.

+ Reply to Thread

           




Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts






Advertise on Talk Stats