diff --git a/spec/reduce_mean.js b/spec/reduce_mean.js
index 91610c9..2d1dedc 100644
--- a/spec/reduce_mean.js
+++ b/spec/reduce_mean.js
@@ -1,15 +1,15 @@
 var
 	data  = [
-		{ id :  1, g : "A", w : 1,   x :   10 },
-		{ id :  2, g : "A", w : 3,   x :    4 },
-		{ id :  3, g : "A", w : 2,   x :    2 },
-		{ id :  4, g : "A", w : 0,   x :    0 },
-		{ id :  5, g : "A", w : 1,   x :    2 },
-		{ id :  6, g : "B", w : 2.5, x :    0 },
-		{ id :  7, g : "B", w : 10,  x : 0.15 },
-		{ id :  8, g : "B", w : 5.2, x : 0.09 },
-		{ id :  9, g : "B", w : 0.2, x :  0.2 },
-		{ id : 10, g : "B", w : 2,   x :  0.1 }
+		{ id :  1, g : "A", w : 1,   x :  10 },
+		{ id :  2, g : "A", w : 3,   x :   4 },
+		{ id :  3, g : "A", w : 2,   x :   2 },
+		{ id :  4, g : "A", w : 0,   x :  10 },
+		{ id :  5, g : "A", w : 1,   x :   2 },
+		{ id :  6, g : "B", w : 10,  x :   0 },
+		{ id :  7, g : "B", w : 10,  x :   2 },
+		{ id :  8, g : "B", w : 4,   x :   2 },
+		{ id :  9, g : "B", w : 0.2, x : 0.2 },
+		{ id : 10, g : "B", w : 2,   x :  10 }
 	],
 	cross   = require('crossfilter')(data),
 	decimal = require('decimal.js'),
@@ -22,7 +22,7 @@ describe('Reduce by (weighted) mean', function() {
 
 	var  
 		dimf        = cross.dimension(function(d){ return d.id; }),
-		dimg        = cross.dimension(function(d){ return d.f; }),
+		dimg        = cross.dimension(function(d){ return d.g; }),
 		red_x       = function(d){ return d.x },
 		red_w       = function(d){ return d.w },
 
@@ -77,55 +77,55 @@ describe('Reduce by (weighted) mean', function() {
 
 	describe('When weight function is not provided, it sets weight to 1 for every data point', function() {
 
-        it('whole dataset to 1.854', function() {
+        it('whole dataset to 4.22', function() {
             reduceVal = reduceAcc_1( reduceAll_1.value() );
-            expect(reduceVal).toBe(1.854);
+            expect(reduceVal).toBe(4.22);
         });
 
 	});
 
-	// describe('calculates reduction values correctly using arbitrary precision arithmetic', function() {
+	describe('calculates reduction values correctly using arbitrary precision arithmetic', function() {
 
- //        it('whole dataset to 18.6', function() {
- //            reduceVal = reduceAcc( reduceAll.value() );
- //            expect(reduceVal).toBe(18.6);
- //        });
+        it('whole dataset to 2.2903614457831325', function() {
+            reduceVal = reduceAcc_w( reduceAll_w.value() );
+            expect(reduceVal).toBe(2.2903614457831325);
+        });
 
- //        it('group A to 18', function() {
-	// 	 	dimf.filter('A');
-	// 	 	reduceVal = reduceAcc( reduce.all()[0].value );
-	// 		expect( reduceVal ).toBe(18);
-	// 	});
+        it('group A to 4', function() {
+		 	dimf.filter('A');
+		 	reduceVal = reduceAcc_w( reduce_w.all()[0].value );
+			expect( reduceVal ).toBe(4);
+		});
 
-	// 	it('group B to 0.6', function() {
-	// 	 	dimf.filter('B');
-	// 	 	reduceVal = reduceAcc( reduce.all()[1].value );
-	// 	 	expect( reduceVal ).toBe(0.6);
-	// 	});
+		it('group B to 1.833587786259542', function() {
+		 	dimf.filter('B');
+		 	reduceVal = reduceAcc_w( reduce_w.all()[1].value );
+		 	expect( reduceVal ).toBe(1.833587786259542);
+		});
 
-	// });
+	});
 
-	// describe('also when a dimension is filtered', function() {
+	describe('also when a dimension is filtered', function() {
 
-	// 	beforeEach(function() {
-	// 	    dimf.filter(6);
-	//   	});
+		beforeEach(function() {
+		    dimf.filter(9);
+	  	});
 
- //        it('whole dataset reduced to 0', function() {
- //            reduceVal = reduceAcc( reduceAll.value() );
- //            expect(reduceVal).toBe(0);
- //        });
+        it('whole dataset reduced to 0.2', function() {
+            reduceVal = reduceAcc_w( reduceAll_w.value() );
+            expect(reduceVal).toBe(0.2);
+        });
 
- //        it('group A reduced to 0', function() {
-	// 	 	reduceVal = reduceAcc( reduce.all()[0].value );
-	// 		expect( reduceVal ).toBe(0);
-	// 	});
+        it('group A reduced to 0', function() {
+		 	reduceVal = reduceAcc_w( reduce_w.all()[0].value );
+			expect( reduceVal ).toBe(0);
+		});
 
-	// 	it('group B reduced to 0', function() {
-	// 	 	reduceVal = reduceAcc( reduce.all()[1].value );
-	// 	 	expect( reduceVal ).toBe(0);
-	// 	});
+		it('group B reduced to 0.2', function() {
+		 	reduceVal = reduceAcc_w( reduce_w.all()[1].value );
+		 	expect( reduceVal ).toBe(0.2);
+		});
 
-	// });
+	});
 
 });
\ No newline at end of file