Hi Anderson,
thank you for the response. If I understood it correctly, what you're saying is that to get closer to what I said I would like to find, I need to i.e. compare each emotion to each of my two controls *separately*, and then use PALM. To be honest, 1. I'm not sure whether I'd be able to do that properly, 2. I am kind of running out of time and have, in the meantime, settled for the contrasts below, ran randomise, and am almost about to summarise my results. Could you tell me if proceeding with these would be *wrong per se*? I'm presuming that if I use these and make it clear that I'm comparing (an emotion) with *the mean* of (the two controls/all other stimuli), it should be fine, and while not exactly what I initially envisaged, still meaningful.. is that right?
Also, aren’t F tests also meant for asking logical “or” questions, too? What’s the difference?
OC1 1 0 0 0 0 0
OC2 0 1 0 0 0 0
OC3 0 0 1 0 0 0
OC4 0 0 0 1 0 0
OC5 0 0 0 0 1 0
OC6 0 0 0 0 0 1
OC7 1 0 0 0 -0.5 -0.5
OC8 0 1 0 0 -0.5 -0.5
OC9 0 0 1 0 -0.5 -0.5
OC10 0 0 0 1 -0.5 -0.5
OC11 0.25 0.25 0.25 0.25 0 0
OC12 0.25 0.25 0.25 0.25 -0.5 -0.5
OC13 1 -0.2 -0.2 -0.2 -0.2 -0.2
OC14 -0.2 1 -0.2 -0.2 -0.2 -0.2
OC15 -0.2 -0.2 1 -0.2 -0.2 -0.2
OC16 -0.2 -0.2 -0.2 1 -0.2 -0.2
- OC7 masked with OC1 … OC10 with OC4 => given emotion > mean of controls
- F2 (OC7-10) masked with F1 (OC1-4) => at least one emotion > mean of controls
- OC12 masked with OC11 => mean of emotions > mean of controls
- OC12 masked with OC1 … OC16 masked with OC4 => given emotion > mean of all other stimuli
I actually read a paper today (van der Gaag, 2007) that does something very similar, and mentions using this contrast to compare three emotions vs. neutral: "contrast D+F+H-3N was thresholded at p<.005 and inclusively masked with D+F+H+N at p<.005." I'm doing the same (but using two control conditions simultaneously and not including those when masking), so figured it should actually be fine...
Relying on you to reply to me before I move on to reporting results..
Thank you again!!
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