spm_P_RF: SPM: Returns the [un]corrected P value using unifed EC theory

Description Usage Arguments Value References

Description

spm_P_RF returns the probability of c or more clusters with more than k resels in volume process of R RESELS thresholded at u. All p values can be considered special cases:

spm_P_RF(1,0,z,df,STAT,1,n) = uncorrected p value spm_P_RF(1,0,z,df,STAT,R,n) = corrected p value (based on height z) spm_P_RF(1,k,u,df,STAT,R,n) = corrected p value (based on extent k at u) spm_P_RF(c,k,u,df,STAT,R,n) = corrected p value (based on number c at k and u) spm_P_RF(c,0,u,df,STAT,R,n) = omnibus p value (based on number c at u)

If n > 1 a conjunction probility over the n values of the statistic is returned

Usage

1
[P p Ec Ek] = spm_P_RF(c,k,z,df,STAT,R,n)

Arguments

c

- cluster number

k

- extent RESELS

z

- height minimum over n values

df

- [dfinterest dferror]

STAT

- Statistical field 'Z' - Gaussian field 'T' - T - field 'X' - Chi squared field 'F' - F - field

R

- RESEL Count defining search volume

n

- number of component SPMs in conjunction

Value

A list containing: P - corrected P value - P(C >= c | K >= k) p - uncorrected P value Ec - expected number of clusters (maxima) Ek - expected number of resels per cluster

References

Hasofer AM (1978) Upcrossings of random fields Suppl Adv Appl Prob 10:14-21

Friston KJ et al (1994) Assessing the Significance of Focal Activations Using Their Spatial Extent Human Brain Mapping 1:210-220

Worsley KJ et al (1996) A Unified Statistical Approach for Determining Significant Signals in Images of Cerebral Activation Human Brain Mapping 4:58-73


jpellman/spmR documentation built on May 19, 2019, 10:44 p.m.