diff --git a/matlab/global_initialization.m b/matlab/global_initialization.m
index a4c6cbea4..a481105d8 100644
--- a/matlab/global_initialization.m
+++ b/matlab/global_initialization.m
@@ -46,7 +46,7 @@ function global_initialization()
   
   % Prior draws
   options_.forecast = 0;
-  options_.replic = 0;
+  options_.replic = 1;
   
   % Model
   options_.linear = 0;
@@ -62,4 +62,4 @@ function global_initialization()
   oo_.endo_simul = [];
   oo_.dr = [];
   oo_.exo_det_steady_state = [];
-  oo_.exo_det_simul = [];
\ No newline at end of file
+  oo_.exo_det_simul = [];
diff --git a/matlab/prior_analysis.m b/matlab/prior_analysis.m
index 7077f097e..538f010a1 100644
--- a/matlab/prior_analysis.m
+++ b/matlab/prior_analysis.m
@@ -18,13 +18,14 @@ function prior_analysis(var_list)
   global M_ options_ oo_ estim_params_ bayestopt_
   
   old_options = options_;
-  if options_.replic == 0;
-    options_.replic = 1000;
-    options_.order = 1;
+  if options_.replic < 100
+  warning('Prior analysis requires at least 100 replications, preferably many more! options replic reset to 100')
+    options_.replic = 100;
   end
   
+  options_.order = 1;
   if options_.forecast
     forcst_unc(oo_.endo_simul(:,1:M_.maximum_lag),var_list);
   end
   
-  options_ = old_options;
\ No newline at end of file
+  options_ = old_options;
diff --git a/matlab/stoch_simul.m b/matlab/stoch_simul.m
index bc94967af..ba9af99fc 100644
--- a/matlab/stoch_simul.m
+++ b/matlab/stoch_simul.m
@@ -1,9 +1,9 @@
 % Copyright (C) 2001 Michel Juillard
 %
 function info=stoch_simul(var_list)
-  global M_ options_ oo_
-  
-  global it_
+   global M_ options_ oo_ it_
+
+   options_old = options_;
   options_ = set_default_option(options_,'TeX',0);  
   options_ = set_default_option(options_,'order',2);
   options_ = set_default_option(options_,'linear',0);
@@ -42,6 +42,7 @@ function info=stoch_simul(var_list)
   [oo_.dr, info] = resol(oo_.steady_state,0);
 
   if info(1)
+    options_ = options_old;
     print_info(info);
     return
   end  
@@ -75,6 +76,7 @@ function info=stoch_simul(var_list)
     if options_.periods < options_.drop
       disp(['STOCH_SIMUL error: The horizon of simulation is shorter' ...
 	    ' than the number of observations to be DROPed'])
+      options_ =options_old;
       return
     end
     oo_.endo_simul = simult(repmat(oo_.dr.ys,1,M_.maximum_lag),oo_.dr);
@@ -274,4 +276,6 @@ if isfield(options_,'SpectralDensity')
   if options_.SpectralDensity == 1
     [omega,f] = UnivariateSpectralDensity(oo_.dr,var_list);
   end
-end
\ No newline at end of file
+end
+
+options_ = options_old;