diff --git a/base/bag_test.go b/base/bag_test.go
index f5366ae..485d79c 100644
--- a/base/bag_test.go
+++ b/base/bag_test.go
@@ -35,7 +35,7 @@ func TestBAGSimple(t *testing.T) {
 			} else if name == "2" {
 				attrSpecs[2] = a
 			} else {
-				panic(name)
+				t.Fatalf("Unexpected attribute name '%s'", name)
 			}
 		}
 
@@ -102,7 +102,7 @@ func TestBAG(t *testing.T) {
 			} else if name == "2" {
 				attrSpecs[2] = a
 			} else {
-				panic(name)
+				t.Fatalf("Unexpected attribute name '%s'", name)
 			}
 		}
 
diff --git a/ensemble/randomforest_test.go b/ensemble/randomforest_test.go
index 762125d..3828e8c 100644
--- a/ensemble/randomforest_test.go
+++ b/ensemble/randomforest_test.go
@@ -10,7 +10,7 @@ import (
 func TestRandomForest1(testEnv *testing.T) {
 	inst, err := base.ParseCSVToInstances("../examples/datasets/iris_headers.csv", true)
 	if err != nil {
-		panic(err)
+		testEnv.Fatal("Unable to parse CSV to instances: %s", err.Error())
 	}
 
 	filt := filters.NewChiMergeFilter(inst, 0.90)
diff --git a/filters/binning_test.go b/filters/binning_test.go
index f655717..dfa2518 100644
--- a/filters/binning_test.go
+++ b/filters/binning_test.go
@@ -11,12 +11,12 @@ func TestBinning(t *testing.T) {
 		// Read the data
 		inst1, err := base.ParseCSVToInstances("../examples/datasets/iris_headers.csv", true)
 		if err != nil {
-			panic(err)
+			t.Fatal("Unable to parse CSV to instances: %s", err.Error())
 		}
 
 		inst2, err := base.ParseCSVToInstances("../examples/datasets/iris_binned.csv", true)
 		if err != nil {
-			panic(err)
+			t.Fatal("Unable to parse CSV to instances: %s", err.Error())
 		}
 		//
 		// Construct the binning filter
diff --git a/filters/chimerge_test.go b/filters/chimerge_test.go
index 72ae5be..677d5aa 100644
--- a/filters/chimerge_test.go
+++ b/filters/chimerge_test.go
@@ -9,7 +9,7 @@ import (
 func TestChiMFreqTable(testEnv *testing.T) {
 	inst, err := base.ParseCSVToInstances("../examples/datasets/chim.csv", true)
 	if err != nil {
-		panic(err)
+		testEnv.Fatal("Unable to parse CSV to instances: %s", err.Error())
 	}
 
 	freq := ChiMBuildFrequencyTable(inst.AllAttributes()[0], inst)
@@ -28,7 +28,7 @@ func TestChiMFreqTable(testEnv *testing.T) {
 func TestChiClassCounter(testEnv *testing.T) {
 	inst, err := base.ParseCSVToInstances("../examples/datasets/chim.csv", true)
 	if err != nil {
-		panic(err)
+		testEnv.Fatal("Unable to parse CSV to instances: %s", err.Error())
 	}
 	freq := ChiMBuildFrequencyTable(inst.AllAttributes()[0], inst)
 	classes := chiCountClasses(freq)
@@ -46,7 +46,7 @@ func TestChiClassCounter(testEnv *testing.T) {
 func TestStatisticValues(testEnv *testing.T) {
 	inst, err := base.ParseCSVToInstances("../examples/datasets/chim.csv", true)
 	if err != nil {
-		panic(err)
+		testEnv.Fatal("Unable to parse CSV to instances: %s", err.Error())
 	}
 	freq := ChiMBuildFrequencyTable(inst.AllAttributes()[0], inst)
 	chiVal := chiComputeStatistic(freq[5], freq[6])
@@ -76,11 +76,9 @@ func TestChiSquareDistValues(testEnv *testing.T) {
 }
 
 func TestChiMerge1(testEnv *testing.T) {
-
-	// Read the data
 	inst, err := base.ParseCSVToInstances("../examples/datasets/chim.csv", true)
 	if err != nil {
-		panic(err)
+		testEnv.Fatal("Unable to parse CSV to instances: %s", err.Error())
 	}
 	_, rows := inst.Size()
 
@@ -105,7 +103,7 @@ func TestChiMerge2(testEnv *testing.T) {
 	//   Randy Kerber, ChiMerge: Discretisation of Numeric Attributes, 1992
 	inst, err := base.ParseCSVToInstances("../examples/datasets/iris_headers.csv", true)
 	if err != nil {
-		panic(err)
+		testEnv.Fatal("Unable to parse CSV to instances: %s", err.Error())
 	}
 
 	// Sort the instances
@@ -113,7 +111,7 @@ func TestChiMerge2(testEnv *testing.T) {
 	sortAttrSpecs := base.ResolveAttributes(inst, allAttrs)[0:1]
 	instSorted, err := base.Sort(inst, base.Ascending, sortAttrSpecs)
 	if err != nil {
-		panic(err)
+		testEnv.Fatalf("Sort failed: %s", err.Error())
 	}
 
 	// Perform Chi-Merge
@@ -179,7 +177,7 @@ func TestChiMerge4(testEnv *testing.T) {
 	//   Randy Kerber, ChiMerge: Discretisation of Numeric Attributes, 1992
 	inst, err := base.ParseCSVToInstances("../examples/datasets/iris_headers.csv", true)
 	if err != nil {
-		panic(err)
+		testEnv.Fatal("Unable to parse CSV to instances: %s", err.Error())
 	}
 
 	filt := NewChiMergeFilter(inst, 0.90)
@@ -191,7 +189,9 @@ func TestChiMerge4(testEnv *testing.T) {
 	if len(clsAttrs) != 1 {
 		testEnv.Fatalf("%d != %d", len(clsAttrs), 1)
 	}
-	if clsAttrs[0].GetName() != "Species" {
-		panic("Class Attribute wrong!")
+	firstClassAttributeName := clsAttrs[0].GetName()
+	expectedClassAttributeName := "Species"
+	if firstClassAttributeName != expectedClassAttributeName {
+		testEnv.Fatalf("Expected class attribute '%s'; actual class attribute '%s'", expectedClassAttributeName, firstClassAttributeName)
 	}
 }
diff --git a/meta/bagging_test.go b/meta/bagging_test.go
index 651f4f8..9443cf7 100644
--- a/meta/bagging_test.go
+++ b/meta/bagging_test.go
@@ -13,7 +13,7 @@ import (
 func BenchmarkBaggingRandomForestFit(testEnv *testing.B) {
 	inst, err := base.ParseCSVToInstances("../examples/datasets/iris_headers.csv", true)
 	if err != nil {
-		panic(err)
+		testEnv.Fatal("Unable to parse CSV to instances: %s", err.Error())
 	}
 
 	rand.Seed(time.Now().UnixNano())
@@ -38,7 +38,7 @@ func BenchmarkBaggingRandomForestFit(testEnv *testing.B) {
 func BenchmarkBaggingRandomForestPredict(testEnv *testing.B) {
 	inst, err := base.ParseCSVToInstances("../examples/datasets/iris_headers.csv", true)
 	if err != nil {
-		panic(err)
+		testEnv.Fatal("Unable to parse CSV to instances: %s", err.Error())
 	}
 
 	rand.Seed(time.Now().UnixNano())
@@ -64,7 +64,7 @@ func BenchmarkBaggingRandomForestPredict(testEnv *testing.B) {
 func TestRandomForest1(testEnv *testing.T) {
 	inst, err := base.ParseCSVToInstances("../examples/datasets/iris_headers.csv", true)
 	if err != nil {
-		panic(err)
+		testEnv.Fatal("Unable to parse CSV to instances: %s", err.Error())
 	}
 	trainData, testData := base.InstancesTrainTestSplit(inst, 0.6)
 
diff --git a/neural/layered_test.go b/neural/layered_test.go
index e9c52f6..98443c3 100644
--- a/neural/layered_test.go
+++ b/neural/layered_test.go
@@ -140,7 +140,7 @@ func TestLayeredXOR(t *testing.T) {
 				for _, a := range pred.AllAttributes() {
 					af, ok := a.(*base.FloatAttribute)
 					if !ok {
-						panic("All of these should be FloatAttributes!")
+						t.Fatalf("Expected all attributes to be FloatAttributes; actually some were not")
 					}
 					af.Precision = 1
 				}
diff --git a/trees/tree_test.go b/trees/tree_test.go
index 1912177..d20089f 100644
--- a/trees/tree_test.go
+++ b/trees/tree_test.go
@@ -11,7 +11,7 @@ import (
 func TestRandomTree(testEnv *testing.T) {
 	inst, err := base.ParseCSVToInstances("../examples/datasets/iris_headers.csv", true)
 	if err != nil {
-		panic(err)
+		testEnv.Fatal("Unable to parse CSV to instances: %s", err.Error())
 	}
 
 	filt := filters.NewChiMergeFilter(inst, 0.90)
@@ -30,7 +30,7 @@ func TestRandomTree(testEnv *testing.T) {
 func TestRandomTreeClassification(testEnv *testing.T) {
 	inst, err := base.ParseCSVToInstances("../examples/datasets/iris_headers.csv", true)
 	if err != nil {
-		panic(err)
+		testEnv.Fatal("Unable to parse CSV to instances: %s", err.Error())
 	}
 	trainData, testData := base.InstancesTrainTestSplit(inst, 0.6)
 
@@ -55,7 +55,7 @@ func TestRandomTreeClassification(testEnv *testing.T) {
 func TestRandomTreeClassification2(testEnv *testing.T) {
 	inst, err := base.ParseCSVToInstances("../examples/datasets/iris_headers.csv", true)
 	if err != nil {
-		panic(err)
+		testEnv.Fatal("Unable to parse CSV to instances: %s", err.Error())
 	}
 	trainData, testData := base.InstancesTrainTestSplit(inst, 0.4)
 
@@ -78,7 +78,7 @@ func TestRandomTreeClassification2(testEnv *testing.T) {
 func TestPruning(testEnv *testing.T) {
 	inst, err := base.ParseCSVToInstances("../examples/datasets/iris_headers.csv", true)
 	if err != nil {
-		panic(err)
+		testEnv.Fatal("Unable to parse CSV to instances: %s", err.Error())
 	}
 	trainData, testData := base.InstancesTrainTestSplit(inst, 0.6)
 
@@ -120,7 +120,7 @@ func TestInformationGain(testEnv *testing.T) {
 func TestID3Inference(testEnv *testing.T) {
 	inst, err := base.ParseCSVToInstances("../examples/datasets/tennis.csv", true)
 	if err != nil {
-		panic(err)
+		testEnv.Fatal("Unable to parse CSV to instances: %s", err.Error())
 	}
 
 	// Build the decision tree
@@ -170,7 +170,7 @@ func TestID3Inference(testEnv *testing.T) {
 func TestID3Classification(testEnv *testing.T) {
 	inst, err := base.ParseCSVToInstances("../examples/datasets/iris_headers.csv", true)
 	if err != nil {
-		panic(err)
+		testEnv.Fatal("Unable to parse CSV to instances: %s", err.Error())
 	}
 
 	filt := filters.NewBinningFilter(inst, 10)
@@ -194,7 +194,7 @@ func TestID3Classification(testEnv *testing.T) {
 func TestID3(testEnv *testing.T) {
 	inst, err := base.ParseCSVToInstances("../examples/datasets/tennis.csv", true)
 	if err != nil {
-		panic(err)
+		testEnv.Fatal("Unable to parse CSV to instances: %s", err.Error())
 	}
 
 	// Build the decision tree