In the recently published article an error was included in figure 1. In Model II, a line from X self to Y self was included in error.
Original Version
![](https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary-alt:20170620101006-25848-mediumThumb-S003329171700037X_fig1g.jpg?pub-status=live)
Fig. 1.
Corrected Version – the arrow has been removed
![](https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary-alt:20170620101006-87761-mediumThumb-S003329171700037X_fig2g.jpg?pub-status=live)
Fig. 1.
Online ordering is currently unavailable due to technical issues. We apologise for any delays responding to customers while we resolve this. For further updates please visit our website: https://www.cambridge.org/news-and-insights/technical-incident
Published online by Cambridge University Press: 11 April 2017
In the recently published article an error was included in figure 1. In Model II, a line from X self to Y self was included in error.
Original Version
Fig. 1.
Corrected Version – the arrow has been removed
Fig. 1.
Fig. 1.
Fig. 1.