There were a number of errors in Fig. 1 in the paper by Mitchell et al. (Reference Mitchell2010) for which the authors apologize.
![](https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary-alt:20161210093320-21173-mediumThumb-S0033291710000917_fig1g.jpg?pub-status=live)
Fig. 1. Only four items per twin are shown. Λ1.1 denotes the factor loading for the first item, for twin 1. A1.1 denotes the residual variance due to A for the first item, for twin 1. r a.1=1.0 or 0.5 and denotes the twin correlation for the residual components due to A for the first item, etc. r c.1=1.0 and denotes the twin correlation for the residual components due to C for the first item, etc.
The correct version of Fig. 1 is given on the following page.