The “mshocks” block now accepts the “learnt_in” option

doc/manual/source/the-model-file.rst

@@ -4050,7 +4050,7 @@ and ``endval`` blocks which are given a special ``learnt_in`` option.
     can be replaced by the ``multiply`` keyword.
 
     The ``overwrite`` option says that this block cancels and replaces previous
-    ``shocks`` blocks that have the same ``learnt_in`` option.
+    ``shocks`` and ``mshocks`` blocks that have the same ``learnt_in`` option.
 
     Note that a ``shocks(learnt_in=1)`` block is equivalent to a regular
     :bck:`shocks` block.
@@ -4124,6 +4124,49 @@ and ``endval`` blocks which are given a special ``learnt_in`` option.
     Those values will be the realized ones, unless there is another
     ``endval(learnt_in=p)`` block with ``p>3``.
 
+.. block:: mshocks(learnt_in=INTEGER) ;
+           mshocks(learnt_in=INTEGER,overwrite) ;
+
+    |br| The ``mshocks(learnt_in=INTEGER)`` syntax can be used to specify temporary
+    shocks that are learnt in a specific period, specified in a multiplicative
+    way. It should contain one or more occurences of the following group of
+    three lines, with the same semantics as a regular :bck:`mshocks` block::
+
+      var VARIABLE_NAME;
+      periods INTEGER[:INTEGER] [[,] INTEGER[:INTEGER]]...;
+      values DOUBLE | (EXPRESSION)  [[,] DOUBLE | (EXPRESSION) ]...;
+
+    As in the regular :bck:`mshocks` block (without the ``learnt_in`` option),
+    the values are interpreted as a multiplicative factor over the steady state
+    value of the exogenous variable, either the initial steady state as given
+    by ``initval`` if there is no ``endval`` block, or the terminal steady
+    state if there is an ``endval`` block. Note that in the latter case, it is
+    the terminal steady state as anticipated from the period given in the
+    ``learnt_in`` option that is used for the computation.
+
+    The ``overwrite`` option says that this block cancels and replaces previous
+    ``shocks`` and ``mshocks`` blocks that have the same ``learnt_in`` option.
+
+    Note that a ``mshocks(learnt_in=1)`` block is equivalent to a regular
+    :bck:`mshocks` block.
+
+    *Example*
+
+    ::
+
+        mshocks(learnt_in=2);
+          var x;
+          periods 3:4;
+          values 1.1;
+        end;
+
+    This syntax means that from the perspective of period 2, ``x`` in periods 3
+    and 4 is expected to be equal to 1.1 times its steady state. If there is no
+    ``endval`` block, the initial steady state as given by ``initval`` is used;
+    if there is an ``endval`` block, the terminal steady state as anticipated
+    from the perspective of period 2 is used (as specified in the relevant
+    ``endval(learnt_in=…`` block)).
+
 .. command:: perfect_foresight_with_expectation_errors_setup ;
              perfect_foresight_with_expectation_errors_setup (OPTIONS...);
 

matlab/perfect-foresight-models/perfect_foresight_with_expectation_errors_setup.m

@@ -117,6 +117,8 @@ else
                         oo_.pfwee.shocks_info(exo_id, prds, p) = oo_.pfwee.shocks_info(exo_id, prds, p) + M_.learnt_shocks(j).value;
                     case 'multiply'
                         oo_.pfwee.shocks_info(exo_id, prds, p) = oo_.pfwee.shocks_info(exo_id, prds, p) .* M_.learnt_shocks(j).value;
+                    case 'multiply_steady_state'
+                        oo_.pfwee.shocks_info(exo_id, prds, p) = oo_.pfwee.terminal_info(exo_id, p) * M_.learnt_shocks(j).value;
                     otherwise
                         error('Unknown type in M_.learnt_shocks')
                 end

preprocessor

@@ -1 +1 @@
-Subproject commit 6ec7f580d577848509d07e05f2120d4bab8c32e6
+Subproject commit 6af84b8cac54777bc97d4bc232452f8cf9b4498c

tests/deterministic_simulations/pfwee_learnt_in.mod

@@ -1,5 +1,5 @@
 /* Tests perfect_foresight_with_expectation_errors_{setup,solver}
-   using the shocks(learnt_in=…) and endval(learnt_in=…) syntax */
+   using the shocks(learnt_in=…), mshocks(learnt_in=…) and endval(learnt_in=…) syntax */
 
 var c k;
 varexo x;
@@ -45,8 +45,14 @@ end;
 
 shocks(learnt_in = 3);
   var x;
-  periods 3 7;
-  values 1.4 1.5;
+  periods 3;
+  values 1.4;
+end;
+
+mshocks(learnt_in = 3);
+  var x;
+  periods 7;
+  values (1.5/1.2); // 1.2 is the terminal steady as anticipated in period 3
 end;
 
 endval(learnt_in = 3);
@@ -106,7 +112,7 @@ oo_.exo_simul = [ saved_exo; oo_.exo_simul ];
 
 // Information arriving in period 3 (temp shocks + permanent shock in future)
 oo_.exo_simul(4,1) = 1.4;
-oo_.exo_simul(8,1) = 1.5;
+oo_.exo_simul(8,1) = (1.5/1.3)*1.3;
 oo_.exo_steady_state = 1.1+0.1;
 oo_.exo_simul(end, 1) = oo_.exo_steady_state;
 oo_.steady_state = evaluate_steady_state(oo_.steady_state, oo_.exo_steady_state, M_, options_, true);