diff --git a/engine-proto/gram-test/tetrahedron-radius-ratio.jl b/engine-proto/gram-test/tetrahedron-radius-ratio.jl
index bde7272..6172aa3 100644
--- a/engine-proto/gram-test/tetrahedron-radius-ratio.jl
+++ b/engine-proto/gram-test/tetrahedron-radius-ratio.jl
@@ -29,7 +29,7 @@ for j in 1:10
         push!(values, -1/BigFloat(3))
         filled = true
       elseif k == 5
-        push!(values, 1)
+        push!(values, -1)
         filled = true
       elseif k <= 9 && k - j != 5
         push!(values, 0)
@@ -37,7 +37,7 @@ for j in 1:10
       end
     elseif k <= 4
       if j == 5
-        push!(values, 1)
+        push!(values, -1)
         filled = true
       elseif j <= 9 && j - k != 5
         push!(values, 0)
@@ -59,8 +59,8 @@ guess = hcat(
     1  1 -1 -1  0
     1 -1  1 -1  0
     1 -1 -1  1  0
-    0  0  0  0  1.5
-    1  1  1  1  0.5
+    0  0  0  0 -1.5
+    1  1  1  1 -0.5
   ] + 0.2*Engine.rand_on_shell(fill(BigFloat(-1), 5)),
   Engine.point([-1, -1, -1]),
   Engine.point([ 1, -1, -1]),