diff --git a/pmml-evaluator/src/main/java/org/jpmml/evaluator/visitors/AttributeOptimizerBattery.java b/pmml-evaluator/src/main/java/org/jpmml/evaluator/visitors/AttributeOptimizerBattery.java
index f5c6c50e..f306534f 100644
--- a/pmml-evaluator/src/main/java/org/jpmml/evaluator/visitors/AttributeOptimizerBattery.java
+++ b/pmml-evaluator/src/main/java/org/jpmml/evaluator/visitors/AttributeOptimizerBattery.java
@@ -24,7 +24,7 @@ public class AttributeOptimizerBattery extends VisitorBattery {
 
 	public AttributeOptimizerBattery(){
 		add(ValueParser.class);
+		add(NodeScoreParser.class);
 		add(TargetCategoryParser.class);
-		add(NodeScoreOptimizer.class);
 	}
 }
\ No newline at end of file
diff --git a/pmml-evaluator/src/main/java/org/jpmml/evaluator/visitors/NodeScoreOptimizer.java b/pmml-evaluator/src/main/java/org/jpmml/evaluator/visitors/NodeScoreParser.java
similarity index 56%
rename from pmml-evaluator/src/main/java/org/jpmml/evaluator/visitors/NodeScoreOptimizer.java
rename to pmml-evaluator/src/main/java/org/jpmml/evaluator/visitors/NodeScoreParser.java
index 70490dae..6a86fead 100644
--- a/pmml-evaluator/src/main/java/org/jpmml/evaluator/visitors/NodeScoreOptimizer.java
+++ b/pmml-evaluator/src/main/java/org/jpmml/evaluator/visitors/NodeScoreParser.java
@@ -18,12 +18,18 @@
  */
 package org.jpmml.evaluator.visitors;
 
+import org.dmg.pmml.DataType;
 import org.dmg.pmml.MathContext;
 import org.dmg.pmml.MiningFunction;
+import org.dmg.pmml.PMMLObject;
 import org.dmg.pmml.VisitorAction;
 import org.dmg.pmml.tree.DecisionTree;
 import org.dmg.pmml.tree.Node;
+import org.dmg.pmml.tree.PMMLAttributes;
 import org.dmg.pmml.tree.TreeModel;
+import org.jpmml.evaluator.MissingAttributeException;
+import org.jpmml.evaluator.TypeCheckException;
+import org.jpmml.evaluator.TypeUtil;
 import org.jpmml.model.visitors.AbstractVisitor;
 import org.jpmml.model.visitors.Resettable;
 
@@ -32,7 +38,7 @@
  * A Visitor that pre-parses the score attribute of regression-type tree models.
  * </p>
  */
-public class NodeScoreOptimizer extends AbstractVisitor implements Resettable {
+public class NodeScoreParser extends AbstractVisitor implements Resettable {
 
 	private MathContext mathContext = null;
 
@@ -42,6 +48,28 @@ public void reset(){
 		this.mathContext = null;
 	}
 
+	@Override
+	public void pushParent(PMMLObject parent){
+		super.pushParent(parent);
+
+		if(parent instanceof TreeModel){
+			TreeModel treeModel = (TreeModel)parent;
+
+			this.mathContext = treeModel.getMathContext();
+		}
+	}
+
+	@Override
+	public PMMLObject popParent(){
+		PMMLObject parent = super.popParent();
+
+		if(parent instanceof TreeModel){
+			this.mathContext = null;
+		}
+
+		return parent;
+	}
+
 	@Override
 	public VisitorAction visit(DecisionTree decisionTree){
 		throw new UnsupportedOperationException();
@@ -50,21 +78,15 @@ public VisitorAction visit(DecisionTree decisionTree){
 	@Override
 	public VisitorAction visit(TreeModel treeModel){
 		MiningFunction miningFunction = treeModel.getMiningFunction();
+		if(miningFunction == null){
+			throw new MissingAttributeException(treeModel, PMMLAttributes.TREEMODEL_MININGFUNCTION);
+		}
 
-		if(miningFunction != null){
-
-			switch(miningFunction){
-				case REGRESSION:
-					this.mathContext = treeModel.getMathContext();
-					break;
-				default:
-					this.mathContext = null;
-					break;
-			}
-		} // End if
-
-		if(this.mathContext == null){
-			return VisitorAction.SKIP;
+		switch(miningFunction){
+			case REGRESSION:
+				break;
+			default:
+				return VisitorAction.SKIP;
 		}
 
 		return super.visit(treeModel);
@@ -72,31 +94,39 @@ public VisitorAction visit(TreeModel treeModel){
 
 	@Override
 	public VisitorAction visit(Node node){
-		MathContext mathContext = this.mathContext;
 
-		if(mathContext != null && node.hasScore()){
+		if(node.hasScore()){
 			Object score = node.getScore();
 
 			if(score instanceof String){
-				String stringScore = (String)score;
-
-				try {
-					switch(mathContext){
-						case DOUBLE:
-							node.setScore(Double.parseDouble(stringScore));
-							break;
-						case FLOAT:
-							node.setScore(Float.parseFloat(stringScore));
-							break;
-						default:
-							break;
-					}
-				} catch(NumberFormatException nfe){
-					// Ignored
-				}
+				score = parseScore(score);
+
+				node.setScore(score);
 			}
 		}
 
 		return super.visit(node);
 	}
+
+	private Object parseScore(Object score){
+
+		if(score == null){
+			return score;
+		}
+
+		try {
+			switch(this.mathContext){
+				case DOUBLE:
+					return TypeUtil.parseOrCast(DataType.DOUBLE, score);
+				case FLOAT:
+					return TypeUtil.parseOrCast(DataType.FLOAT, score);
+				default:
+					break;
+			}
+		} catch(IllegalArgumentException | TypeCheckException e){
+			// Ignored
+		}
+
+		return score;
+	}
 }
\ No newline at end of file
diff --git a/pmml-evaluator/src/test/java/org/jpmml/evaluator/visitors/NodeScoreOptimizerTest.java b/pmml-evaluator/src/test/java/org/jpmml/evaluator/visitors/NodeScoreParserTest.java
similarity index 96%
rename from pmml-evaluator/src/test/java/org/jpmml/evaluator/visitors/NodeScoreOptimizerTest.java
rename to pmml-evaluator/src/test/java/org/jpmml/evaluator/visitors/NodeScoreParserTest.java
index 29e25a30..94a24e6f 100644
--- a/pmml-evaluator/src/test/java/org/jpmml/evaluator/visitors/NodeScoreOptimizerTest.java
+++ b/pmml-evaluator/src/test/java/org/jpmml/evaluator/visitors/NodeScoreParserTest.java
@@ -34,7 +34,7 @@
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertSame;
 
-public class NodeScoreOptimizerTest {
+public class NodeScoreParserTest {
 
 	@Test
 	public void parseAndIntern(){
@@ -54,7 +54,7 @@ public void parseAndIntern(){
 			.setMathContext(MathContext.FLOAT);
 
 		VisitorBattery visitorBattery = new VisitorBattery();
-		visitorBattery.add(NodeScoreOptimizer.class);
+		visitorBattery.add(NodeScoreParser.class);
 		visitorBattery.add(FloatInterner.class);
 
 		visitorBattery.applyTo(treeModel);