PowerPoint Presentation - Group Analysis with AFNI Programs

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Paired t-Test: Cartoon Data

Signal

Condition

# 1

Condition

# 2

• Paired means that samples in different conditions should be linked together (e.g., from same subjects)

•

• Test determines if differences between conditions in each pair are “large” compared to SEM of the differences

•

• Paired test can detect systematic intra-subject differences that can be hidden in inter-subject variations

•

• Lesson: properly separating inter-subject and intra-subject signal variations can be very important!

• Significantly different!

• Condition #2 > #1, per subject

paired

differences

paired data

samples:

same numbers

as before