GameObject won't move to Transform Position

I'm attempting to map spheres to joint positions, and so far I've just started with the head. I've been able to get the Vector3 of the head and floor the values, and I've successfully instantiated the sphere, but when it comes to actually moving the sphere to the head position, I'm unsuccessful. When I write the sphere's position to the log with each update, the position is correct--that is, it'll say, for example (-15, -115, 106) as it's supposed to, but as soon as I run the scene, the sphere itself either remains at the origin, or disappears. Any advice? public class returnJoints : MonoBehaviour

 {
 
         GameObject sphereHead;
 
  
 
     void Awake()
 
     {
 
         sphereHead = GameObject.CreatePrimitive(PrimitiveType.Sphere);
 
         sphereHead.renderer.material.color = Color.blue;
 
         sphereHead.transform.localScale = new Vector3(.25f, .25f, .25f);
 
         
 
     }
 
  
 
     void Update()
 
     {
 
         Omek.JointID jointID = Omek.JointID.head;
 
         ReturnCode rc;
 
  
 
         // get the head position in world space
 
         OmekFramework.Common.BasicTypes.SpaceTypes.Vector3 worldPosition;
 
         rc = BeckonData.Persons[0].Skeleton[jointID].Position.World.Get(out worldPosition);
 
         //floor the vector3 values
 
         float headX = Mathf.Floor(worldPosition.x);
 
         float headY = Mathf.Floor(worldPosition.y);
 
         float headZ = Mathf.Floor(worldPosition.z);
 
         Vector3 headPos = new Vector3(headX, headY, headZ);
 
         //place a sphere at the head's position
 
         Vector3 headSpherePos = new Vector3(headX, headY, headZ);
 
         sphereHead.transform.position = headSpherePos;
 
  
 
  
 
         //Debug.Log("head " + worldPosition);
 
         Debug.Log("head (floor): " + headPos);
 
         Debug.Log("sphere position (head): " + sphereHead.transform.position);
 
  
 
         
 
     }
 
 }