fix">)</mo></mrow><annotation encoding="application/x-tex">(0, 1)</annotation></semantics></math>
interval (as in the previous analyses). The second set of models assumes
that there is no clustering, i.e., the correlation of random effects
<math display="inline" xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>ρ</mi><mo>=</mo><mn>0</mn></mrow><annotation encoding="application/x-tex">\rho = 0</annotation></semantics></math>,
which simplifies the structured covariance matrix to a diagonal matr