diff --git a/src/muz_qe/pdr_context.cpp b/src/muz_qe/pdr_context.cpp
index 21ad6b1ee..95e7fb792 100644
--- a/src/muz_qe/pdr_context.cpp
+++ b/src/muz_qe/pdr_context.cpp
@@ -97,7 +97,6 @@ namespace pdr {
             np += m_levels[i].size();
         } 
         st.update("PDR num properties", np); 
-        std::cout << m_stats.m_num_propagations << " " << np << "\n";
     }
 
     void pred_transformer::reset_statistics() {
@@ -1501,7 +1500,14 @@ namespace pdr {
             simplify_formulas();
             m_last_result = l_false;
             TRACE("pdr",  display_certificate(tout););      
-            IF_VERBOSE(1, display_certificate(verbose_stream()););
+            IF_VERBOSE(1, {
+                    expr_ref_vector refs(m);
+                    vector<relation_info> rs;
+                    get_level_property(m_inductive_lvl, refs, rs);    
+                    model_converter_ref mc;
+                    inductive_property ex(m, mc, rs);
+                    verbose_stream() << ex.to_string();
+                });
             validate();
             return l_false;
         }
diff --git a/src/muz_qe/pdr_dl_interface.cpp b/src/muz_qe/pdr_dl_interface.cpp
index 19c604162..532019025 100644
--- a/src/muz_qe/pdr_dl_interface.cpp
+++ b/src/muz_qe/pdr_dl_interface.cpp
@@ -251,8 +251,8 @@ void dl_interface::collect_params(param_descrs& p) {
                             "checking for reachability (not only during cube weakening)"););
     PRIVATE_PARAMS(p.insert(":max-num-contexts", CPK_UINT, "PDR: (default 500) maximal number of contexts to create"););
     PRIVATE_PARAMS(p.insert(":try-minimize-core", CPK_BOOL, "PDR: (default false) try to reduce core size (before inductive minimization)");); 
-    PRIVATE_PARAMS(p.insert(":simplify-formulas-pre", CPK_BOOL, "PDR: (default false) simplify derived formulas before inductive propagation"););
-    PRIVATE_PARAMS(p.insert(":simplify-formulas-post", CPK_BOOL, "PDR: (default false) simplify derived formulas after inductive propagation"););
+    p.insert(":simplify-formulas-pre", CPK_BOOL, "PDR: (default false) simplify derived formulas before inductive propagation");
+    p.insert(":simplify-formulas-post", CPK_BOOL, "PDR: (default false) simplify derived formulas after inductive propagation");
     p.insert(":slice", CPK_BOOL, "PDR: (default true) simplify clause set using slicing");
     p.insert(":coalesce-rules", CPK_BOOL, "BMC: (default false) coalesce rules");
 }
diff --git a/src/muz_qe/pdr_util.cpp b/src/muz_qe/pdr_util.cpp
index f4d8fd557..512d94956 100644
--- a/src/muz_qe/pdr_util.cpp
+++ b/src/muz_qe/pdr_util.cpp
@@ -324,13 +324,12 @@ expr_ref_vector model_evaluator::prune_by_cone_of_influence(ptr_vector<expr> con
     unsigned sz = m_model->get_num_constants();
     expr_ref e(m), eq(m);
     expr_ref_vector model(m);
-    bool_rewriter rw(m);
     for (unsigned i = 0; i < sz; i++) {
         func_decl * d = m_model->get_constant(i); 
         expr* val = m_model->get_const_interp(d);
         e = m.mk_const(d);
         if (m_visited.is_marked(e)) {
-            rw.mk_eq(e, val, eq);
+            eq = m.mk_eq(e, val);
             model.push_back(eq);
         }
     }