Exploiting the nature of DTI that it is calculated from multiple diffusion-weighted images of each region, permutation testing, a non-parametric hypothesis testing technique, was modified for the analysis of serial DTI data and implemented for voxel-wise hypothesis tests of diffusion metric changes, as well as for suprathreshold cluster analysis to correct for multiple comparisons.
One objection to p-value adjustments is that the significance of each test will be interpreted according to how many outcome measures are considered in the family-wise hypothesis, which has been defined ambiguously, arbitrarily and inconsistently by its advocates.
where (chi _{i,b}^{overline {text {MAP}}}) denotes the bit-wise counter hypothesis of the MAP hypothesis, which is obtained by searching over all the solutions with the b th bit of the i th symbol opposite to the current MAP hypothesis.
As this was an exploratory study, instead of a confirmatory study with an increasing number of family-wise null hypotheses to test, we have refrained from a Bonferroni-like correction to change the significance level α = 0.05 [ 24].
That factors into Wise's own hypothesis, which he posted in a six-part blog post last February: that the plane was hijacked on Vladimir Putin's instruction.
As an alternative to shotgun accumulation of large omic data sets, phenotypic data gathering can be done in a step-wise progression for hypothesis driven research.
To control for the family-wise α-error, hypotheses 1 3 were tested in a sequential manner according to a closed test principle.
We heuristically sample from the null hypothesis by (group-wise) shuffling the expression values for each gene independently.
We examined point-wise departures from the null hypothesis using permutation tests if the global statistic indicated that location was significant at the 0.05 level.
For comparisons between treatments, a Logit model for Categorical Data Analysis was used followed by pair-wise comparisons using Generalized Linear Hypothesis Testing with each cage acting as a replicate.
If the global statistic indicated that location was a statistically significant predictor of disability generally, we next evaluated location-specific (point-wise) departures from the null hypothesis using the same set of permutations [ 18, 31].
