diff --git a/mushroom_rl/core/_impl/type_conversions.py b/mushroom_rl/core/_impl/type_conversions.py
index 01c1609f..02a61527 100644
--- a/mushroom_rl/core/_impl/type_conversions.py
+++ b/mushroom_rl/core/_impl/type_conversions.py
@@ -45,11 +45,11 @@ def to_backend_array(cls, array):
         raise NotImplementedError
 
     @staticmethod
-    def zeros(*dims):
+    def zeros(*dims, dtype):
         raise NotImplementedError
 
     @staticmethod
-    def ones(*dims):
+    def ones(*dims, dtype):
         raise NotImplementedError
 
 
@@ -67,12 +67,12 @@ def to_backend_array(cls, array):
         return cls.to_numpy(array)
 
     @staticmethod
-    def zeros(*dims):
-        return np.zeros(dims)
+    def zeros(*dims, dtype=float):
+        return np.zeros(dims, dtype=dtype)
 
     @staticmethod
-    def ones(*dims):
-        return np.ones(dims)
+    def ones(*dims, dtype=float):
+        return np.ones(dims, dtype=dtype)
 
 
 class TorchConversion(DataConversion):
@@ -89,12 +89,12 @@ def to_backend_array(cls, array):
         return cls.to_torch(array)
 
     @staticmethod
-    def zeros(*dims):
-        return torch.zeros(*dims, device=TorchUtils.get_device())
+    def zeros(*dims, dtype=torch.float32):
+        return torch.zeros(*dims, dtype=dtype, device=TorchUtils.get_device())
 
     @staticmethod
-    def ones(*dims):
-        return torch.ones(*dims, device=TorchUtils.get_device())
+    def ones(*dims, dtype=torch.float32):
+        return torch.ones(*dims, dtype=dtype, device=TorchUtils.get_device())
 
 
 class ListConversion(DataConversion):
@@ -111,12 +111,12 @@ def to_backend_array(cls, array):
         return cls.to_numpy(array)
 
     @staticmethod
-    def zeros(*dims):
-        return np.zeros(dims)
+    def zeros(*dims, dtype=float):
+        return np.zeros(dims, dtype=float)
 
     @staticmethod
-    def ones(*dims):
-        return np.ones(dims)
+    def ones(*dims, dtype=float):
+        return np.ones(dims, dtype=float)