diff --git a/src/test/java/org/mastodon/mamut/feature/dimensionalityreduction/RandomDataTools.java b/src/test/java/org/mastodon/mamut/feature/dimensionalityreduction/RandomDataTools.java
index dcd5c56c0..7a92a0f2a 100644
--- a/src/test/java/org/mastodon/mamut/feature/dimensionalityreduction/RandomDataTools.java
+++ b/src/test/java/org/mastodon/mamut/feature/dimensionalityreduction/RandomDataTools.java
@@ -4,8 +4,6 @@
 
 public class RandomDataTools
 {
-	private static final Random random = new Random( 42 );
-
 	public static double[][] generateSampleData()
 	{
 		return generateSampleData( 50, 100 );
@@ -32,6 +30,8 @@ private static double[][] generateRandomPointsInSphere( double centerX, double c
 	{
 		double[][] points = new double[ numberOfPoints ][ 3 ];
 
+		final Random random = new Random( 42 );
+
 		for ( int i = 0; i < numberOfPoints; i++ )
 		{
 			double r = radius * Math.cbrt( random.nextDouble() );
diff --git a/src/test/java/org/mastodon/mamut/feature/dimensionalityreduction/tsne/TSneDemo.java b/src/test/java/org/mastodon/mamut/feature/dimensionalityreduction/tsne/TSneDemo.java
index 799e37a7a..978f11738 100644
--- a/src/test/java/org/mastodon/mamut/feature/dimensionalityreduction/tsne/TSneDemo.java
+++ b/src/test/java/org/mastodon/mamut/feature/dimensionalityreduction/tsne/TSneDemo.java
@@ -16,7 +16,7 @@ public static void main( final String[] args )
 		TSneConfiguration config = setUpTSne( inputData );
 		BarnesHutTSne tsne = new ParallelBHTsne(); // according to https://github.com/lejon/T-SNE-Java/ the parallel version is faster at same accuracy
 		double[][] tsneResult = tsne.tsne( config );
-		PlotPoints.plot( inputData, tsneResult, resultValues -> resultValues[ 0 ] > 10 );
+		PlotPoints.plot( inputData, tsneResult, resultValues -> resultValues[ 0 ] > 18 );
 	}
 
 	static TSneConfiguration setUpTSne( double[][] inputData )
diff --git a/src/test/java/org/mastodon/mamut/feature/dimensionalityreduction/tsne/TSneTest.java b/src/test/java/org/mastodon/mamut/feature/dimensionalityreduction/tsne/TSneTest.java
index a9736f4b1..5ce8c9ec6 100644
--- a/src/test/java/org/mastodon/mamut/feature/dimensionalityreduction/tsne/TSneTest.java
+++ b/src/test/java/org/mastodon/mamut/feature/dimensionalityreduction/tsne/TSneTest.java
@@ -70,8 +70,8 @@ void test()
 		assertEquals( 2, tsneResult[ 0 ].length );
 
 		for ( int i = 0; i < numCluster1; i++ )
-			assertTrue( tsneResult[ i ][ 0 ] > 10 );
+			assertTrue( tsneResult[ i ][ 0 ] > 18 );
 		for ( int i = numCluster1; i < numCluster1 + numCluster2; i++ )
-			assertTrue( tsneResult[ i ][ 0 ] < 10 );
+			assertTrue( tsneResult[ i ][ 0 ] < 18 );
 	}
 }
diff --git a/src/test/java/org/mastodon/mamut/feature/dimensionalityreduction/umap/UmapTest.java b/src/test/java/org/mastodon/mamut/feature/dimensionalityreduction/umap/UmapTest.java
index 12f45ce0e..e8b4148e1 100644
--- a/src/test/java/org/mastodon/mamut/feature/dimensionalityreduction/umap/UmapTest.java
+++ b/src/test/java/org/mastodon/mamut/feature/dimensionalityreduction/umap/UmapTest.java
@@ -6,13 +6,13 @@
  * %%
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
- * 
+ *
  * 1. Redistributions of source code must retain the above copyright notice,
  *    this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright notice,
  *    this list of conditions and the following disclaimer in the documentation
  *    and/or other materials provided with the distribution.
- * 
+ *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
@@ -48,8 +48,8 @@ void test()
 		assertEquals( umapResult.length, sampleData.length );
 		assertEquals( 2, umapResult[ 0 ].length );
 		for ( int i = 0; i < 50; i++ )
-			assertTrue( umapResult[ i ][ 0 ] < 0 );
-		for ( int i = 50; i < 150; i++ )
 			assertTrue( umapResult[ i ][ 0 ] > 0 );
+		for ( int i = 50; i < 150; i++ )
+			assertTrue( umapResult[ i ][ 0 ] < 0 );
 	}
 }