diff --git a/contribs/discrete_mode_choice/src/main/java/org/matsim/contribs/discrete_mode_choice/components/utils/NullWaitingTimeEstimator.java b/contribs/discrete_mode_choice/src/main/java/org/matsim/contribs/discrete_mode_choice/components/utils/NullWaitingTimeEstimator.java
index 445451713ca..e003a9f09e9 100644
--- a/contribs/discrete_mode_choice/src/main/java/org/matsim/contribs/discrete_mode_choice/components/utils/NullWaitingTimeEstimator.java
+++ b/contribs/discrete_mode_choice/src/main/java/org/matsim/contribs/discrete_mode_choice/components/utils/NullWaitingTimeEstimator.java
@@ -1,5 +1,8 @@
 package org.matsim.contribs.discrete_mode_choice.components.utils;
 
+import java.util.List;
+
+import org.matsim.api.core.v01.population.PlanElement;
 import org.matsim.pt.routes.TransitPassengerRoute;
 
 /**
@@ -9,8 +12,15 @@
  * @author sebhoerl
  */
 public class NullWaitingTimeEstimator implements PTWaitingTimeEstimator {
+
 	@Override
 	public double estimateWaitingTime(double agentDepartureTime, TransitPassengerRoute route) {
 		return 0.0;
 	}
+
+	@Override
+	public double estimateWaitingTime(List<? extends PlanElement> elements) {
+		return 0.0;
+	}
+
 }
diff --git a/contribs/discrete_mode_choice/src/main/java/org/matsim/contribs/discrete_mode_choice/components/utils/PTWaitingTimeEstimator.java b/contribs/discrete_mode_choice/src/main/java/org/matsim/contribs/discrete_mode_choice/components/utils/PTWaitingTimeEstimator.java
index 2b4da256f0b..25804cddb95 100644
--- a/contribs/discrete_mode_choice/src/main/java/org/matsim/contribs/discrete_mode_choice/components/utils/PTWaitingTimeEstimator.java
+++ b/contribs/discrete_mode_choice/src/main/java/org/matsim/contribs/discrete_mode_choice/components/utils/PTWaitingTimeEstimator.java
@@ -1,5 +1,8 @@
 package org.matsim.contribs.discrete_mode_choice.components.utils;
 
+import java.util.List;
+
+import org.matsim.api.core.v01.population.PlanElement;
 import org.matsim.pt.routes.TransitPassengerRoute;
 
 /**
@@ -11,5 +14,9 @@
  * @author sebhoerl
  */
 public interface PTWaitingTimeEstimator {
+
 	double estimateWaitingTime(double departureTime, TransitPassengerRoute route);
+
+	double estimateWaitingTime(List<? extends PlanElement> elements);
+
 }
diff --git a/contribs/discrete_mode_choice/src/main/java/org/matsim/contribs/discrete_mode_choice/components/utils/ScheduleWaitingTimeEstimator.java b/contribs/discrete_mode_choice/src/main/java/org/matsim/contribs/discrete_mode_choice/components/utils/ScheduleWaitingTimeEstimator.java
index 2ab5bfe10ca..6fc60d7ad73 100644
--- a/contribs/discrete_mode_choice/src/main/java/org/matsim/contribs/discrete_mode_choice/components/utils/ScheduleWaitingTimeEstimator.java
+++ b/contribs/discrete_mode_choice/src/main/java/org/matsim/contribs/discrete_mode_choice/components/utils/ScheduleWaitingTimeEstimator.java
@@ -8,6 +8,7 @@
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.matsim.api.core.v01.Id;
+import org.matsim.api.core.v01.TransportMode;
 import org.matsim.api.core.v01.population.Leg;
 import org.matsim.api.core.v01.population.PlanElement;
 import org.matsim.core.utils.collections.Tuple;
@@ -54,17 +55,14 @@ private Tuple<Id<TransitLine>, Id<TransitRoute>> createId(TransitLine transitLin
 		return new Tuple<>(transitLine.getId(), transitRoute.getId());
 	}
 
+	@Override
 	public double estimateWaitingTime(List<? extends PlanElement> elements) {
 		double totalWaitingTime = 0.0;
 
 		for (PlanElement element : elements) {
-			if (element instanceof Leg) {
-				Leg leg = (Leg) element;
-
-				if (leg.getMode().equals("pt")) {
-					TransitPassengerRoute route = (TransitPassengerRoute) leg.getRoute();
-					totalWaitingTime += estimateWaitingTime(leg.getDepartureTime().seconds(), route);
-				}
+			if (element instanceof Leg leg && leg.getMode().equals(TransportMode.pt)) {
+				TransitPassengerRoute route = (TransitPassengerRoute) leg.getRoute();
+				totalWaitingTime += this.estimateWaitingTime(leg.getDepartureTime().seconds(), route);
 			}
 		}