diff --git a/examples/input.nn.recommended b/examples/input.nn.recommended
index 17ee56cfd..42b0a770f 100644
--- a/examples/input.nn.recommended
+++ b/examples/input.nn.recommended
@@ -41,7 +41,8 @@ memorize_symfunc_results                       # Keep symmetry function results
 test_fraction                   0.1            # Fraction of structures kept for testing.
 force_weight                    10.0           # Weight of force updates relative to energy updates.
 short_energy_fraction           1.000          # Fraction of energy updates per epoch.
-short_force_fraction            0.02315        # Fraction of force updates per epoch.
+#short_force_fraction            0.02315        # Fraction of force updates per epoch (not necessary if force_energy_ratio given).
+force_energy_ratio              10.0           # Specifies ratio between force and energy updates (ratio = updates_force / updates_energy).
 short_energy_error_threshold    0.00           # RMSE threshold for energy update candidates.
 short_force_error_threshold     1.00           # RMSE threshold for force update candidates.
 rmse_threshold_trials           3              # Maximum number of RMSE threshold trials.
diff --git a/src/libnnp/Mode.h b/src/libnnp/Mode.h
index dbd9e0865..12298573c 100644
--- a/src/libnnp/Mode.h
+++ b/src/libnnp/Mode.h
@@ -91,6 +91,8 @@ class Mode
     };
 
     Mode();
+    virtual ~Mode() {};
+
     /** Write welcome message with version information.
      */
     void                     initialize();
diff --git a/src/libnnp/Settings.cpp b/src/libnnp/Settings.cpp
index 063e6ef2e..76ce23a78 100644
--- a/src/libnnp/Settings.cpp
+++ b/src/libnnp/Settings.cpp
@@ -68,6 +68,7 @@ map<string, shared_ptr<Settings::Key>> const createKnownKeywordsMap()
     m["rmse_threshold_trials_charge"  ] = "";
     m["energy_fraction"               ] = "";
     m["force_fraction"                ] = "";
+    m["force_energy_ratio"            ] = "";
     m["charge_fraction"               ] = "";
     m["use_old_weights_short"         ] = "";
     m["use_old_weights_charge"        ] = "";
diff --git a/src/libnnpif/LAMMPS/InterfaceLammps.h b/src/libnnpif/LAMMPS/InterfaceLammps.h
index d896cedf0..8c1d21a7e 100644
--- a/src/libnnpif/LAMMPS/InterfaceLammps.h
+++ b/src/libnnpif/LAMMPS/InterfaceLammps.h
@@ -31,6 +31,7 @@ class InterfaceLammps : public Mode
 {
 public:
     InterfaceLammps();
+    virtual ~InterfaceLammps() {};
 
     /** Initialize the LAMMPS interface.
      *
diff --git a/src/libnnptrain/Training.cpp b/src/libnnptrain/Training.cpp
index 602454c2b..f7bed9b66 100644
--- a/src/libnnptrain/Training.cpp
+++ b/src/libnnptrain/Training.cpp
@@ -2874,7 +2874,30 @@ void Training::setupUpdatePlan(string const& property)
     // Actual property modified here.
     Property& pa = p[property];
     string keyword = property + "_fraction";
-    pa.epochFraction = atof(settings[keyword].c_str());
+
+    // Override force fraction if keyword "energy_force_ratio" is provided.
+    if (property == "force" &&
+        p.exists("energy") &&
+        settings.keywordExists("force_energy_ratio"))
+    {
+        double const ratio = atof(settings["force_energy_ratio"].c_str());
+        if (settings.keywordExists(keyword))
+        {
+            log << "WARNING: Given force fraction is ignored because "
+                   "force/energy ratio is provided.\n";
+        }
+        log << strpr("Desired force/energy update ratio              : %.6f\n",
+                     ratio);
+        log << "----------------------------------------------\n";
+        pa.epochFraction = (p["energy"].numTrainPatterns * ratio)
+                         / p["force"].numTrainPatterns;
+    }
+    // Default action = read "<property>_fraction" keyword.
+    else
+    {
+        pa.epochFraction = atof(settings[keyword].c_str());
+    }
+
     keyword = "task_batch_size_" + property;
     pa.taskBatchSize = (size_t)atoi(settings[keyword].c_str());
     if (pa.taskBatchSize == 0)
@@ -2933,8 +2956,12 @@ void Training::setupUpdatePlan(string const& property)
     log << "Update plan for property \"" + property + "\":\n";
     log << strpr("- Per-task batch size                          : %zu\n",
                  pa.taskBatchSize);
-    log << strpr("- Fraction of patterns used per epoch          : %.4f\n",
+    log << strpr("- Fraction of patterns used per epoch          : %.6f\n",
                  pa.epochFraction);
+    if (pa.numUpdates == 0)
+    {
+        log << "WARNING: No updates are planned for this property.";
+    }
     log << strpr("- Updates per epoch                            : %zu\n",
                  pa.numUpdates);
     log << strpr("- Patterns used per update (rank %3d / global) : "