diff --git a/matlab/unstable_examples/+imuSimulator/covarianceAnalysisBetween.m b/matlab/unstable_examples/+imuSimulator/covarianceAnalysisBetween.m
index 1419f1773..feb840ad4 100644
--- a/matlab/unstable_examples/+imuSimulator/covarianceAnalysisBetween.m
+++ b/matlab/unstable_examples/+imuSimulator/covarianceAnalysisBetween.m
@@ -11,25 +11,26 @@ clc
 clear all
 close all
 
-saveResults = 0;
+saveResults = 1;
 
 %% Configuration
 options.useRealData = 1;           % controls whether or not to use the real data (if available) as the ground truth traj
-options.includeBetweenFactors = 0; % if true, BetweenFactors will be added between consecutive poses
+options.includeBetweenFactors = 1; % if true, BetweenFactors will be added between consecutive poses
 
 options.includeIMUFactors = 1;     % if true, IMU factors will be added between consecutive states (biases, poses, velocities)
 options.imuFactorType = 1;         % Set to 1 or 2 to use IMU type 1 or type 2 factors (will default to type 1)
-options.imuNonzeroBias = 0;        % if true, a nonzero bias is applied to IMU measurements
+options.imuNonzeroBias = 1;        % if true, a nonzero bias is applied to IMU measurements
 
 options.includeCameraFactors = 0;  % not fully implementemeasurements, values, noiseModels, measurementNoise, options, metadatad yet
 numberOfLandmarks = 10;            % Total number of visual landmarks, used for camera factors
 
 options.includeGPSFactors = 0;     % if true, GPS factors will be added as priors to poses
+options.gpsStartPose = 100;        % Pose number to start including GPS factors at
 
 options.trajectoryLength = 209;    % length of the ground truth trajectory
 options.subsampleStep = 20;        % number of poses to skip when using real data (to reduce computation on long trajectories)
 
-numMonteCarloRuns = 50;             % number of Monte Carlo runs to perform
+numMonteCarloRuns = 100;             % number of Monte Carlo runs to perform
 
 %% Camera metadata
 K = Cal3_S2(500,500,0,640/2,480/2); % Camera calibration
@@ -53,8 +54,8 @@ metadata.imu.zeroBias = imuBias.ConstantBias(zeros(3,1), zeros(3,1));
 metadata.imu.AccelerometerSigma = 1e-3;
 metadata.imu.GyroscopeSigma = 1e-5;
 metadata.imu.IntegrationSigma = 1e-5;
-metadata.imu.BiasAccelerometerSigma = metadata.imu.epsBias;
-metadata.imu.BiasGyroscopeSigma = metadata.imu.epsBias;  
+metadata.imu.BiasAccelerometerSigma = 1e-4; %metadata.imu.epsBias;
+metadata.imu.BiasGyroscopeSigma = 1e-4; %metadata.imu.epsBias;  
 metadata.imu.BiasAccOmegaInit = metadata.imu.epsBias;
 metadata.imu.g = [0;0;0];
 metadata.imu.omegaCoriolis = [0;0;0];
@@ -154,8 +155,8 @@ for k=1:numMonteCarloRuns
 
   % Create a random bias for each run
   if options.imuNonzeroBias == 1
-    metadata.imu.accelBiasVector = metadata.imu.BiasAccelerometerSigma .* randn(3,1);
-    metadata.imu.gyroBiasVector = metadata.imu.BiasGyroscopeSigma .* randn(3,1);
+    metadata.imu.accelConstantBiasVector = metadata.imu.BiasAccelerometerSigma .* randn(3,1);
+    metadata.imu.gyroConstantBiasVector = metadata.imu.BiasGyroscopeSigma .* randn(3,1);
   else
     metadata.imu.accelConstantBiasVector = zeros(3,1);
     metadata.imu.gyroConstantBiasVector = zeros(3,1);
diff --git a/matlab/unstable_examples/+imuSimulator/covarianceAnalysisCreateFactorGraph.m b/matlab/unstable_examples/+imuSimulator/covarianceAnalysisCreateFactorGraph.m
index 921d42679..b134a08d3 100644
--- a/matlab/unstable_examples/+imuSimulator/covarianceAnalysisCreateFactorGraph.m
+++ b/matlab/unstable_examples/+imuSimulator/covarianceAnalysisCreateFactorGraph.m
@@ -146,7 +146,7 @@ for i=0:length(measurements)
     end % end of Camera factor creation
     
     %% Add GPS factors
-    if options.includeGPSFactors == 1
+    if options.includeGPSFactors == 1 && i >= options.gpsStartPose
       gpsPosition = measurements(i).gpsPositionVector ...
           + measurementNoise.gpsNoiseVector .* randn(3,1);
       graph.add(PriorFactorPose3(currentPoseKey, ...