diff --git a/src/source/the-model-file.rst b/src/source/the-model-file.rst
index 64c910835..137d3295f 100644
--- a/src/source/the-model-file.rst
+++ b/src/source/the-model-file.rst
@@ -3162,7 +3162,7 @@ Computing the stochastic solution
 
        Value used to split stable from unstable eigenvalues in
        reordering the Generalized Schur decomposition used for solving
-       1st-order problems. Default: ``1.000001`` (except when
+       first order problems. Default: ``1.000001`` (except when
        estimating with ``lik_init`` option equal to ``1``: the default
        is ``0.999999`` in that case; see :ref:`estim`).