diff --git a/presto-main/src/main/java/com/facebook/presto/operator/aggregation/DoubleRegressionAggregation.java b/presto-main/src/main/java/com/facebook/presto/operator/aggregation/DoubleRegressionAggregation.java
index e42699f2a86c5..24d1c6e61fcf5 100644
--- a/presto-main/src/main/java/com/facebook/presto/operator/aggregation/DoubleRegressionAggregation.java
+++ b/presto-main/src/main/java/com/facebook/presto/operator/aggregation/DoubleRegressionAggregation.java
@@ -84,7 +84,8 @@ public static void regrIntercept(@AggregationState RegressionState state, BlockB
     public static void regrSxy(@AggregationState RegressionState state, BlockBuilder out)
     {
         double result = getRegressionSxy(state);
-        if (Double.isFinite(result)) {
+        double count = getRegressionCount(state);
+        if (Double.isFinite(result) && Double.isFinite(count) && count > 0) {
             DOUBLE.writeDouble(out, result);
         }
         else {
@@ -97,7 +98,8 @@ public static void regrSxy(@AggregationState RegressionState state, BlockBuilder
     public static void regrSxx(@AggregationState RegressionState state, BlockBuilder out)
     {
         double result = getRegressionSxx(state);
-        if (Double.isFinite(result)) {
+        double count = getRegressionCount(state);
+        if (Double.isFinite(result) && Double.isFinite(count) && count > 0) {
             DOUBLE.writeDouble(out, result);
         }
         else {
@@ -110,7 +112,8 @@ public static void regrSxx(@AggregationState RegressionState state, BlockBuilder
     public static void regrSyy(@AggregationState RegressionState state, BlockBuilder out)
     {
         double result = getRegressionSyy(state);
-        if (Double.isFinite(result)) {
+        double count = getRegressionCount(state);
+        if (Double.isFinite(result) && Double.isFinite(count) && count > 0) {
             DOUBLE.writeDouble(out, result);
         }
         else {
@@ -136,7 +139,7 @@ public static void regrR2(@AggregationState RegressionState state, BlockBuilder
     public static void regrCount(@AggregationState RegressionState state, BlockBuilder out)
     {
         double result = getRegressionCount(state);
-        if (Double.isFinite(result)) {
+        if (Double.isFinite(result) && result > 0) {
             DOUBLE.writeDouble(out, result);
         }
         else {
@@ -149,7 +152,8 @@ public static void regrCount(@AggregationState RegressionState state, BlockBuild
     public static void regrAvgy(@AggregationState RegressionState state, BlockBuilder out)
     {
         double result = getRegressionAvgy(state);
-        if (Double.isFinite(result)) {
+        double count = getRegressionCount(state);
+        if (Double.isFinite(result) && Double.isFinite(count) && count > 0) {
             DOUBLE.writeDouble(out, result);
         }
         else {
@@ -162,7 +166,8 @@ public static void regrAvgy(@AggregationState RegressionState state, BlockBuilde
     public static void regrAvgx(@AggregationState RegressionState state, BlockBuilder out)
     {
         double result = getRegressionAvgx(state);
-        if (Double.isFinite(result)) {
+        double count = getRegressionCount(state);
+        if (Double.isFinite(result) && Double.isFinite(count) && count > 0) {
             DOUBLE.writeDouble(out, result);
         }
         else {
diff --git a/presto-main/src/main/java/com/facebook/presto/operator/aggregation/RealRegressionAggregation.java b/presto-main/src/main/java/com/facebook/presto/operator/aggregation/RealRegressionAggregation.java
index 7b2943f8fac2b..1fe5d006da1a9 100644
--- a/presto-main/src/main/java/com/facebook/presto/operator/aggregation/RealRegressionAggregation.java
+++ b/presto-main/src/main/java/com/facebook/presto/operator/aggregation/RealRegressionAggregation.java
@@ -84,7 +84,8 @@ public static void regrIntercept(@AggregationState RegressionState state, BlockB
     public static void regrSxy(@AggregationState RegressionState state, BlockBuilder out)
     {
         double result = getRegressionSxy(state);
-        if (Double.isFinite(result)) {
+        double count = getRegressionCount(state);
+        if (Double.isFinite(result) && Double.isFinite(count) && count > 0) {
             REAL.writeLong(out, floatToRawIntBits((float) result));
         }
         else {
@@ -97,7 +98,8 @@ public static void regrSxy(@AggregationState RegressionState state, BlockBuilder
     public static void regrSxx(@AggregationState RegressionState state, BlockBuilder out)
     {
         double result = getRegressionSxx(state);
-        if (Double.isFinite(result)) {
+        double count = getRegressionCount(state);
+        if (Double.isFinite(result) && Double.isFinite(count) && count > 0) {
             REAL.writeLong(out, floatToRawIntBits((float) result));
         }
         else {
@@ -110,7 +112,8 @@ public static void regrSxx(@AggregationState RegressionState state, BlockBuilder
     public static void regrSyy(@AggregationState RegressionState state, BlockBuilder out)
     {
         double result = getRegressionSyy(state);
-        if (Double.isFinite(result)) {
+        double count = getRegressionCount(state);
+        if (Double.isFinite(result) && Double.isFinite(count) && count > 0) {
             REAL.writeLong(out, floatToRawIntBits((float) result));
         }
         else {
@@ -136,7 +139,7 @@ public static void regrR2(@AggregationState RegressionState state, BlockBuilder
     public static void regrCount(@AggregationState RegressionState state, BlockBuilder out)
     {
         double result = getRegressionCount(state);
-        if (Double.isFinite(result)) {
+        if (Double.isFinite(result) && result > 0) {
             REAL.writeLong(out, floatToRawIntBits((float) result));
         }
         else {
@@ -149,7 +152,8 @@ public static void regrCount(@AggregationState RegressionState state, BlockBuild
     public static void regrAvgy(@AggregationState RegressionState state, BlockBuilder out)
     {
         double result = getRegressionAvgy(state);
-        if (Double.isFinite(result)) {
+        double count = getRegressionCount(state);
+        if (Double.isFinite(result) && Double.isFinite(count) && count > 0) {
             REAL.writeLong(out, floatToRawIntBits((float) result));
         }
         else {
@@ -162,7 +166,8 @@ public static void regrAvgy(@AggregationState RegressionState state, BlockBuilde
     public static void regrAvgx(@AggregationState RegressionState state, BlockBuilder out)
     {
         double result = getRegressionAvgx(state);
-        if (Double.isFinite(result)) {
+        double count = getRegressionCount(state);
+        if (Double.isFinite(result) && Double.isFinite(count) && count > 0) {
             REAL.writeLong(out, floatToRawIntBits((float) result));
         }
         else {
diff --git a/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestDoubleRegrAvgxAggregation.java b/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestDoubleRegrAvgxAggregation.java
index 22c39514c64c6..a16feba9528ce 100644
--- a/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestDoubleRegrAvgxAggregation.java
+++ b/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestDoubleRegrAvgxAggregation.java
@@ -29,7 +29,7 @@ protected String getFunctionName()
     public Object getExpectedValue(int start, int length)
     {
         if (length == 0) {
-            return 0.0;
+            return null;
         }
 
         double expected = 0.0;
diff --git a/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestDoubleRegrAvgyAggregation.java b/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestDoubleRegrAvgyAggregation.java
index 02446f7e716e1..028385fc60504 100644
--- a/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestDoubleRegrAvgyAggregation.java
+++ b/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestDoubleRegrAvgyAggregation.java
@@ -29,7 +29,7 @@ protected String getFunctionName()
     public Object getExpectedValue(int start, int length)
     {
         if (length == 0) {
-            return 0.0;
+            return null;
         }
 
         double expected = 0.0;
diff --git a/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestDoubleRegrCountAggregation.java b/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestDoubleRegrCountAggregation.java
index 8a471cfd8c829..e7e253d92024e 100644
--- a/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestDoubleRegrCountAggregation.java
+++ b/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestDoubleRegrCountAggregation.java
@@ -30,7 +30,10 @@ protected String getFunctionName()
     @Override
     public Object getExpectedValue(int start, int length)
     {
-        if (length <= 1) {
+        if (length == 0) {
+            return null;
+        }
+        else if (length == 1) {
             return (double) length;
         }
         else {
diff --git a/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestDoubleRegrSxxAggregation.java b/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestDoubleRegrSxxAggregation.java
index 7d07463e06033..ac185912c4351 100644
--- a/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestDoubleRegrSxxAggregation.java
+++ b/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestDoubleRegrSxxAggregation.java
@@ -30,7 +30,10 @@ protected String getFunctionName()
     @Override
     public Object getExpectedValue(int start, int length)
     {
-        if (length <= 1) {
+        if (length == 0) {
+            return null;
+        }
+        else if (length == 1) {
             return (double) 0;
         }
         else {
diff --git a/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestDoubleRegrSxyAggregation.java b/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestDoubleRegrSxyAggregation.java
index d7b37ad9ac1a9..2d83d8d65e4b9 100644
--- a/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestDoubleRegrSxyAggregation.java
+++ b/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestDoubleRegrSxyAggregation.java
@@ -30,7 +30,10 @@ protected String getFunctionName()
     @Override
     public Object getExpectedValue(int start, int length)
     {
-        if (length <= 1) {
+        if (length == 0) {
+            return null;
+        }
+        else if (length == 1) {
             return (double) 0;
         }
         else {
diff --git a/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestDoubleRegrSyyAggregation.java b/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestDoubleRegrSyyAggregation.java
index 49de8dbe1d63a..4fcfdf8f31b12 100644
--- a/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestDoubleRegrSyyAggregation.java
+++ b/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestDoubleRegrSyyAggregation.java
@@ -30,7 +30,10 @@ protected String getFunctionName()
     @Override
     public Object getExpectedValue(int start, int length)
     {
-        if (length <= 1) {
+        if (length == 0) {
+            return null;
+        }
+        else if (length <= 1) {
             return (double) 0;
         }
         else {
diff --git a/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestRealRegrAvgxAggregation.java b/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestRealRegrAvgxAggregation.java
index 8b2500874f1a8..71eaf42287211 100644
--- a/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestRealRegrAvgxAggregation.java
+++ b/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestRealRegrAvgxAggregation.java
@@ -29,7 +29,7 @@ protected String getFunctionName()
     public Object getExpectedValue(int start, int length)
     {
         if (length == 0) {
-            return 0.0f;
+            return null;
         }
 
         float expected = 0.0f;
diff --git a/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestRealRegrAvgyAggregation.java b/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestRealRegrAvgyAggregation.java
index 6bb7e1ca203b4..6582f6d95b25e 100644
--- a/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestRealRegrAvgyAggregation.java
+++ b/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestRealRegrAvgyAggregation.java
@@ -29,7 +29,7 @@ protected String getFunctionName()
     public Object getExpectedValue(int start, int length)
     {
         if (length == 0) {
-            return 0.0f;
+            return null;
         }
 
         float expected = 0.0f;
diff --git a/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestRealRegrCountAggregation.java b/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestRealRegrCountAggregation.java
index cb4f9148d33e5..eceb7bbb941b1 100644
--- a/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestRealRegrCountAggregation.java
+++ b/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestRealRegrCountAggregation.java
@@ -30,7 +30,10 @@ protected String getFunctionName()
     @Override
     public Object getExpectedValue(int start, int length)
     {
-        if (length <= 1) {
+        if (length == 0) {
+            return null;
+        }
+        else if (length == 1) {
             return (float) length;
         }
         else {
diff --git a/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestRealRegrSxxAggregation.java b/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestRealRegrSxxAggregation.java
index 6bf77d3b114d7..d72fbfba72e38 100644
--- a/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestRealRegrSxxAggregation.java
+++ b/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestRealRegrSxxAggregation.java
@@ -30,7 +30,10 @@ protected String getFunctionName()
     @Override
     public Object getExpectedValue(int start, int length)
     {
-        if (length <= 1) {
+        if (length == 0) {
+            return null;
+        }
+        else if (length == 1) {
             return (float) 0;
         }
         else {
diff --git a/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestRealRegrSxyAggregation.java b/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestRealRegrSxyAggregation.java
index ff4a8b94cab7f..f83ec729c19f5 100644
--- a/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestRealRegrSxyAggregation.java
+++ b/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestRealRegrSxyAggregation.java
@@ -30,7 +30,10 @@ protected String getFunctionName()
     @Override
     public Object getExpectedValue(int start, int length)
     {
-        if (length <= 1) {
+        if (length == 0) {
+            return null;
+        }
+        else if (length == 1) {
             return (float) 0;
         }
         else {
diff --git a/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestRealRegrSyyAggregation.java b/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestRealRegrSyyAggregation.java
index cefe9eb547412..115d0ced316a1 100644
--- a/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestRealRegrSyyAggregation.java
+++ b/presto-main/src/test/java/com/facebook/presto/operator/aggregation/TestRealRegrSyyAggregation.java
@@ -30,7 +30,10 @@ protected String getFunctionName()
     @Override
     public Object getExpectedValue(int start, int length)
     {
-        if (length <= 1) {
+        if (length == 0) {
+            return null;
+        }
+        else if (length <= 1) {
             return (float) 0;
         }
         else {