From: From correlation to causation networks: a simple approximate learning algorithm and its application to high-dimensional plant gene expression data
Definition
True value
Estimate
Covariance matrix:
cov(X k , X l ) = σ kl
Σ = (σ kl )
S= (s kl )
Concentration matrix:
Ω = Σ-1
Ω = (ω kl )
Variances:
var(X k ) = σ kk = σ k 2 MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaaiiGacqWFdpWCdaqhaaWcbaGaem4AaSgabaGaeGOmaidaaaaa@30F4@
σ kk
s kk
Partial variances
var(X k |X≠k) = σ ˜ k k MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaaiiGacuWFdpWCgaacamaaBaaaleaacqWGRbWAcqWGRbWAaeqaaaaa@316F@ = σ ˜ k 2 MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaaiiGacuWFdpWCgaacamaaDaaaleaacqWGRbWAaeaacqaIYaGmaaaaaa@3103@ = ω k k − 1 MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaaiiGacqWFjpWDdaqhaaWcbaGaem4AaSMaem4AaSgabaGaeyOeI0IaeGymaedaaaaa@3348@
σ ˜ k k MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaaiiGacuWFdpWCgaacamaaBaaaleaacqWGRbWAcqWGRbWAaeqaaaaa@316F@
s ˜ k k MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaacuWGZbWCgaacamaaBaaaleaacqWGRbWAcqWGRbWAaeqaaaaa@3114@
Correlations:
corr(X k , X l ) = ρ kl = σ kl (σ kk σ ll )-1/2
P= (ρ kl )
R= (r kl )
Partial correlations:
corr(X k , X l |X≠k, l) = ρ ˜ k l = − ω k l ( ω k k ω l l ) − 1 / 2 MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaaiiGacuWFbpGCgaacamaaBaaaleaacqWGRbWAcqWGSbaBaeqaaOGaeyypa0JaeyOeI0Iae8xYdC3aaSbaaSqaaiabdUgaRjabdYgaSbqabaGccqGGOaakcqWFjpWDdaWgaaWcbaGaem4AaSMaem4AaSgabeaakiab=L8a3naaBaaaleaacqWGSbaBcqWGSbaBaeqaaOGaeiykaKYaaWbaaSqabeaacqGHsislcqaIXaqmcqGGVaWlcqaIYaGmaaaaaa@4739@
P ˜ = ( ρ ˜ k l ) MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaaieWacuWFqbaugaacaiabg2da9maabmaabaacciGaf4xWdiNbaGaadaWgaaWcbaGaem4AaSMaemiBaWgabeaaaOGaayjkaiaawMcaaaaa@3546@
R ˜ = ( r ˜ k l ) MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaaieWacuWFsbGugaacaiabg2da9maabmaabaGafmOCaiNbaGaadaWgaaWcbaGaem4AaSMaemiBaWgabeaaaOGaayjkaiaawMcaaaaa@34F1@