Structural equation model representing the hypothesis that observed intercorrelations amongst response indicator variables (1 – 4) can be explained by a common cause, the generalised response. In contrast to Fig. 1, here we are dealing with specific variables, not concepts and solid outlines are used to represent that difference. Ellipses or circles are characteristically used to denote latent variables and rectangles used to denote observed variables (Grace 2006, Chapter 4).

 
  Part of: Grace JB, Steiner M (2021) A protocol for modelling generalised biological responses using latent variables in structural equation models. One Ecosystem 6: e67320. https://doi.org/10.3897/oneeco.6.e67320