Index: Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Data/DerivedMacroStabilityInwardsOutputFactory.cs
===================================================================
diff -u -r74df3b2f37b578eb5f0d5c8d33379d965805bb8e -r7eb43c9d8cad4783b413a74fe290ba561f3afc03
--- Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Data/DerivedMacroStabilityInwardsOutputFactory.cs	(.../DerivedMacroStabilityInwardsOutputFactory.cs)	(revision 74df3b2f37b578eb5f0d5c8d33379d965805bb8e)
+++ Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Data/DerivedMacroStabilityInwardsOutputFactory.cs	(.../DerivedMacroStabilityInwardsOutputFactory.cs)	(revision 7eb43c9d8cad4783b413a74fe290ba561f3afc03)
@@ -68,7 +68,7 @@
                                                                       contribution);
             double requiredReliability = StatisticsConverter.ProbabilityToReliability(requiredProbability);
 
-            double macroStabilityInwardsReliability = CalculateEstimatedReliability(factorOfStability);
+            double macroStabilityInwardsReliability = CalculateEstimatedReliability(factorOfStability, failureMechanism.GeneralInput.ModelFactor);
             double macroStabilityInwardsProbability = StatisticsConverter.ReliabilityToProbability(macroStabilityInwardsReliability);
 
             double macroStabilityInwardsFactorOfSafety = macroStabilityInwardsReliability / requiredReliability;
@@ -97,13 +97,14 @@
 
         /// <summary>
         /// Calculates the estimated reliability of the macro stability inwards failure mechanism 
-        /// based on the stability factor.
+        /// based on the stability factor and model factor.
         /// </summary>
         /// <param name="factorOfStability">The factory of stability to calculate the reliability for.</param>
-        /// <returns>The estimated reliability based on the stability factor.</returns>
-        private static double CalculateEstimatedReliability(double factorOfStability)
+        /// <param name="modelFactor">The model factor of the calculation result.</param>
+        /// <returns>The estimated reliability based on the stability and model factor.</returns>
+        private static double CalculateEstimatedReliability(double factorOfStability, double modelFactor)
         {
-            return (6.21 * factorOfStability) - 2.88;
+            return ((factorOfStability / modelFactor) - 0.41) / 0.15;
         }
     }
 }
\ No newline at end of file
Index: Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Data.Test/DerivedMacroStabilityInwardsOutputFactoryTest.cs
===================================================================
diff -u -r5c7faf8283e49113a2c7b9e17086148a99f13d2e -r7eb43c9d8cad4783b413a74fe290ba561f3afc03
--- Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Data.Test/DerivedMacroStabilityInwardsOutputFactoryTest.cs	(.../DerivedMacroStabilityInwardsOutputFactoryTest.cs)	(revision 5c7faf8283e49113a2c7b9e17086148a99f13d2e)
+++ Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Data.Test/DerivedMacroStabilityInwardsOutputFactoryTest.cs	(.../DerivedMacroStabilityInwardsOutputFactoryTest.cs)	(revision 7eb43c9d8cad4783b413a74fe290ba561f3afc03)
@@ -109,9 +109,9 @@
 
             // Assert
             Assert.AreEqual(output.FactorOfStability, derivedOutput.FactorOfStability, derivedOutput.FactorOfStability.GetAccuracy());
-            Assert.AreEqual(0.707, derivedOutput.MacroStabilityInwardsFactorOfSafety, derivedOutput.MacroStabilityInwardsFactorOfSafety.GetAccuracy());
-            Assert.AreEqual(0.073605149538226278, derivedOutput.MacroStabilityInwardsProbability, 1e-6);
-            Assert.AreEqual(1.44946, derivedOutput.MacroStabilityInwardsReliability, derivedOutput.MacroStabilityInwardsReliability.GetAccuracy());
+            Assert.AreEqual(0.805, derivedOutput.MacroStabilityInwardsFactorOfSafety, derivedOutput.MacroStabilityInwardsFactorOfSafety.GetAccuracy());
+            Assert.AreEqual(0.049327007121741082, derivedOutput.MacroStabilityInwardsProbability, 1e-6);
+            Assert.AreEqual(1.65141, derivedOutput.MacroStabilityInwardsReliability, derivedOutput.MacroStabilityInwardsReliability.GetAccuracy());
             Assert.AreEqual(0.020161290322580648d, derivedOutput.RequiredProbability, 1e-6);
             Assert.AreEqual(2.05043, derivedOutput.RequiredReliability, derivedOutput.RequiredReliability.GetAccuracy());
             mocks.VerifyAll();
Index: Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Data.Test/MacroStabilityInwardsFailureMechanismSectionResultDetailedAssessmentExtensionsTest.cs
===================================================================
diff -u -r5ac330cbf482b60883be8428b68ab1bde6848eeb -r7eb43c9d8cad4783b413a74fe290ba561f3afc03
--- Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Data.Test/MacroStabilityInwardsFailureMechanismSectionResultDetailedAssessmentExtensionsTest.cs	(.../MacroStabilityInwardsFailureMechanismSectionResultDetailedAssessmentExtensionsTest.cs)	(revision 5ac330cbf482b60883be8428b68ab1bde6848eeb)
+++ Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Data.Test/MacroStabilityInwardsFailureMechanismSectionResultDetailedAssessmentExtensionsTest.cs	(.../MacroStabilityInwardsFailureMechanismSectionResultDetailedAssessmentExtensionsTest.cs)	(revision 7eb43c9d8cad4783b413a74fe290ba561f3afc03)
@@ -143,7 +143,7 @@
 
             macroStabilityInwardsCalculationScenario3.IsRelevant = false;
 
-            var calculations = new[]
+            MacroStabilityInwardsCalculationScenario[] calculations =
             {
                 macroStabilityInwardsCalculationScenario1,
                 macroStabilityInwardsCalculationScenario2,
@@ -154,7 +154,7 @@
             double detailedAssessmentProbability = failureMechanismSectionResult.GetDetailedAssessmentProbability(calculations, failureMechanism, assessmentSection);
 
             // Assert
-            Assert.AreEqual(0.99801160064610306, detailedAssessmentProbability, 1e-8);
+            Assert.AreEqual(0.99686512181936182, detailedAssessmentProbability, 1e-8);
             mocks.VerifyAll();
         }
 
@@ -194,7 +194,7 @@
             FailureMechanismSection section = FailureMechanismSectionTestFactory.CreateFailureMechanismSection();
             var failureMechanismSectionResult = new MacroStabilityInwardsFailureMechanismSectionResult(section);
 
-            var calculationScenarios = new[]
+            MacroStabilityInwardsCalculationScenario[] calculationScenarios =
             {
                 MacroStabilityInwardsCalculationScenarioTestFactory.CreateIrrelevantMacroStabilityInwardsCalculationScenario(section)
             };
@@ -261,7 +261,7 @@
             calculationScenario2.Contribution = (RoundedDouble) contribution2;
             calculationScenario2.Output = MacroStabilityInwardsOutputTestFactory.CreateOutput();
 
-            var calculations = new[]
+            MacroStabilityInwardsCalculationScenario[] calculations =
             {
                 calculationScenario1,
                 calculationScenario2
@@ -350,7 +350,7 @@
 
             MacroStabilityInwardsCalculationScenario macroStabilityInwardsCalculationScenario3 = MacroStabilityInwardsCalculationScenarioTestFactory.CreateIrrelevantMacroStabilityInwardsCalculationScenario(section);
 
-            var calculationScenarios = new[]
+            MacroStabilityInwardsCalculationScenario[] calculationScenarios =
             {
                 macroStabilityInwardsCalculationScenario,
                 macroStabilityInwardsCalculationScenario2,
@@ -438,7 +438,7 @@
             MacroStabilityInwardsCalculationScenario macroStabilityInwardsCalculationScenario = MacroStabilityInwardsCalculationScenarioTestFactory.CreateNotCalculatedMacroStabilityInwardsCalculationScenario(section);
             MacroStabilityInwardsCalculationScenario macroStabilityInwardsCalculationScenario2 = MacroStabilityInwardsCalculationScenarioTestFactory.CreateMacroStabilityInwardsCalculationScenarioWithNaNOutput(section);
 
-            var calculationScenarios = new[]
+            MacroStabilityInwardsCalculationScenario[] calculationScenarios =
             {
                 macroStabilityInwardsCalculationScenario,
                 macroStabilityInwardsCalculationScenario2
Index: Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Forms.Test/PropertyClasses/MacroStabilityInwardsFailureMechanismPropertiesTest.cs
===================================================================
diff -u -r2109804607e2c1041dc78167f44c116f0bee45df -r7eb43c9d8cad4783b413a74fe290ba561f3afc03
--- Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Forms.Test/PropertyClasses/MacroStabilityInwardsFailureMechanismPropertiesTest.cs	(.../MacroStabilityInwardsFailureMechanismPropertiesTest.cs)	(revision 2109804607e2c1041dc78167f44c116f0bee45df)
+++ Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Forms.Test/PropertyClasses/MacroStabilityInwardsFailureMechanismPropertiesTest.cs	(.../MacroStabilityInwardsFailureMechanismPropertiesTest.cs)	(revision 7eb43c9d8cad4783b413a74fe290ba561f3afc03)
@@ -108,7 +108,7 @@
 
             // Assert
             PropertyDescriptorCollection dynamicProperties = PropertiesTestHelper.GetAllVisiblePropertyDescriptors(properties);
-            Assert.AreEqual(9, dynamicProperties.Count);
+            Assert.AreEqual(10, dynamicProperties.Count);
 
             const string generalCategory = "Algemeen";
             const string lengthEffectCategory = "Lengte-effect parameters";
@@ -151,7 +151,7 @@
 
             PropertyDescriptor modelFactorProperty = dynamicProperties[modelFactorPropertyIndex];
             PropertiesTestHelper.AssertRequiredPropertyDescriptorProperties(modelFactorProperty,
-                                                                            generalCategory,
+                                                                            modelSettingsCategory,
                                                                             "Modelfactor [-]",
                                                                             "Modelfactor die wordt gebruikt bij de berekening van de benaderde faalkans op basis van de berekende stabiliteitsfactor.",
                                                                             true);
Index: Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Integration.Test/MacroStabilityInwardsFailureMechanismResultViewIntegrationTest.cs
===================================================================
diff -u -r4190ed11a0efa6f11e5b9c5b767afd8e8db6022b -r7eb43c9d8cad4783b413a74fe290ba561f3afc03
--- Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Integration.Test/MacroStabilityInwardsFailureMechanismResultViewIntegrationTest.cs	(.../MacroStabilityInwardsFailureMechanismResultViewIntegrationTest.cs)	(revision 4190ed11a0efa6f11e5b9c5b767afd8e8db6022b)
+++ Ringtoets/MacroStabilityInwards/test/Ringtoets.MacroStabilityInwards.Integration.Test/MacroStabilityInwardsFailureMechanismResultViewIntegrationTest.cs	(.../MacroStabilityInwardsFailureMechanismResultViewIntegrationTest.cs)	(revision 7eb43c9d8cad4783b413a74fe290ba561f3afc03)
@@ -26,7 +26,6 @@
 using NUnit.Framework;
 using Ringtoets.Common.Data.AssessmentSection;
 using Ringtoets.Common.Data.Calculation;
-using Ringtoets.Common.Data.FailureMechanism;
 using Ringtoets.Common.Forms.Helpers;
 using Ringtoets.Integration.Data;
 using Ringtoets.Integration.TestUtil;
@@ -62,7 +61,7 @@
 
                 // Import failure mechanism sections and ensure the data grid view is updated
                 DataImportHelper.ImportReferenceLine(assessmentSection);
-                IFailureMechanism failureMechanism = assessmentSection.MacroStabilityInwards;
+                MacroStabilityInwardsFailureMechanism failureMechanism = assessmentSection.MacroStabilityInwards;
                 DataImportHelper.ImportFailureMechanismSections(assessmentSection, failureMechanism);
                 Assert.AreEqual(283, dataGridView.Rows.Count);
                 Assert.AreEqual("-", dataGridView.Rows[22].Cells[detailedAssessmentIndex].FormattedValue);
@@ -125,15 +124,19 @@
                     FactorOfStability = 0.5
                 });
                 calculation1.NotifyObservers();
-                Assert.AreEqual(ProbabilityFormattingHelper.Format(0.5),
+                string expectedProbability = ProbabilityFormattingHelper.Format(
+                    DerivedMacroStabilityInwardsOutputFactory.Create(calculation1.Output,
+                                                                     failureMechanism,
+                                                                     assessmentSection).MacroStabilityInwardsProbability);
+                Assert.AreEqual(expectedProbability,
                                 dataGridView.Rows[22].Cells[detailedAssessmentIndex].FormattedValue);
                 Assert.IsEmpty(dataGridView.Rows[22].Cells[detailedAssessmentIndex].ErrorText);
 
                 // Add another, nested calculation without surface line and ensure the data grid view is updated when the surface line is set
                 var calculation3 = new MacroStabilityInwardsCalculationScenario();
                 nestedCalculationGroup.Children.Add(calculation3);
                 nestedCalculationGroup.NotifyObservers();
-                Assert.AreEqual(ProbabilityFormattingHelper.Format(0.5),
+                Assert.AreEqual(expectedProbability,
                                 dataGridView.Rows[22].Cells[detailedAssessmentIndex].FormattedValue);
                 Assert.IsEmpty(dataGridView.Rows[22].Cells[detailedAssessmentIndex].ErrorText);
 
@@ -167,7 +170,7 @@
                 // Set contribution again so we have a probability.
                 calculation1.Contribution = (RoundedDouble) 1.0;
                 calculation1.NotifyObservers();
-                Assert.AreEqual(ProbabilityFormattingHelper.Format(0.5),
+                Assert.AreEqual(expectedProbability,
                                 dataGridView.Rows[22].Cells[detailedAssessmentIndex].FormattedValue);
                 Assert.IsEmpty(dataGridView.Rows[22].Cells[detailedAssessmentIndex].ErrorText);