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. Author manuscript; available in PMC: 2014 Sep 1.
Published in final edited form as: Psychol Methods. 2013 Jul 8;18(3):285–300. doi: 10.1037/a0033266

Table 2.

Brief derivations of the variance of two types of parcels with cross-loadings

Cross-loading with correlated factors Cross-loading with uncorrelated factors
Indicators I2 = T1 + s2 + e2 = U1 + C + s2 + e2
I3 = T1 + s3 + e3 = U1 + C + s3 + e3
I6 = T1 + T2 + s6 + e6 = U1 + C + U2 + C + s6 + e6
I1 = T1 + U3 + s1 + e1 = U1 + C + U3 +s1 + e1
I2 = T1 + s2 + e2 = U1 + C + s2 + e2
I3 = T1 + s3 + e3 = U1 + C + s3 + e3
Parcel
(13)I2+I3+I6
(13)I1+I2+I3
Variance of the parcel
var(13[3U1+4C+U2+s2+s3+s6+e2+e3+e6])
var(13[3U1+3C+U3+s1+s2+s3+e1+e2+e3])
Restated as a covariance
19cov(3U1+4C+U2+s2+s3+s6+e2+e3+e6,3U1+4C+U2+s2+s3+s6+e2+e3+e6)
19cov(3U1+3C+U3+s1+s2+s3+e1+e2+e3,3U1+3C+U3+s1+s2+s3+e1+e2+e3)
Expanded with zero terms removed
19[cov(3U1,3U1)+cov(4C,4C)+cov(U2,U2)+cov(s2,s2)+cov(s3,s3)+cov(s6,s6)+cov(e2,e2)+cov(e3,e3)+cov(e6,e6)]
19[cov(3U1,3U1)+cov(3C,3C)+cov(U3,U3)+cov(s1,s1)+cov(s2,s2)+cov(s3,s3)+cov(e1,e1)+cov(e2,e2)+cov(e3,e3)]
Restated as variances
19[9var(U1)+16var(C)+var(U2)+var(s2)+var(s3)+var(s6)+var(e2)+var(e3)+var(e6)]var(U1)+169var(C)+19[var(U2)+var(s2)+var(s3)+var(s6)+var(e2)+var(e3)+var(e6)]
19[9var(U1)+9var(C)+var(U2)+var(s1)+var(s2)+var(s3)+var(e1)+var(e2)+var(e3)]var(U1)+var(C)+19[var(U3)+var(s1)+var(s2)+var(s3)+var(e1)+var(e2)+var(e3)]

Note. Figure 2 shows the model that describes these items, and all components of the equations.