Fig. 2: A simplified diagram of our CFA model.
From: Extracting stability increases the SNP heritability of emotional problems in young people
Note: Em1 and Em2 are latent emotional problem factors for twin 1 and twin 2. The 24 left-hand variables are observed factor indicators (for each twin), with their variable names as labels (e.g. gp1 = parent-rated SDQ at 7 for twin 1, gp2 = parent-rated SDQ at 7 for twin 2). Twin pairs were allowed to correlate at the latent factor level (shown) and at the scale level (not shown in this figure). Both factors were constrained to a standard normal distribution of mean zero and variance one. Consequently, thresholds, factor loadings and residual variances were all freely estimated, but equated across twins
