diff --git a/bilby/core/utils.py b/bilby/core/utils.py
index 2aabd93f594709a10dff9727ae479fdcdbbb8f06..d058c55995d5c2b183a33065c6668daefe93d4a6 100644
--- a/bilby/core/utils.py
+++ b/bilby/core/utils.py
@@ -59,7 +59,7 @@ def infer_parameters_from_function(func):
     to be removed.
     """
     if isinstance(func, types.MethodType):
-        return _infer_args_from_function_except_n_args(func=func, n=2)
+        return infer_args_from_function_except_n_args(func=func, n=2)
     elif isinstance(func, types.FunctionType):
         return _infer_args_from_function_except_for_first_arg(func=func)
     else:
@@ -77,10 +77,10 @@ def infer_args_from_method(method):
     ---------
     list: A list of strings with the parameters
     """
-    return _infer_args_from_function_except_n_args(func=method, n=1)
+    return infer_args_from_function_except_n_args(func=method, n=1)
 
 
-def _infer_args_from_function_except_n_args(func, n=1):
+def infer_args_from_function_except_n_args(func, n=1):
     """ Inspects a function to find its arguments, and ignoring the
     first n of these, returns a list of arguments from the function's
     signature.
@@ -114,7 +114,7 @@ def _infer_args_from_function_except_n_args(func, n=1):
     >>> def hello(a, b, c, d):
     >>>     pass
     >>>
-    >>> _infer_args_from_function_except_n_args(hello, 2)
+    >>> infer_args_from_function_except_n_args(hello, 2)
     ['c', 'd']
     """
     try:
@@ -126,7 +126,7 @@ def _infer_args_from_function_except_n_args(func, n=1):
 
 
 def _infer_args_from_function_except_for_first_arg(func):
-    return _infer_args_from_function_except_n_args(func=func, n=1)
+    return infer_args_from_function_except_n_args(func=func, n=1)
 
 
 def get_sampling_frequency(time_array):
diff --git a/bilby/hyper/model.py b/bilby/hyper/model.py
index e5c595349712807fd4dcd9af91627d3a5de835c3..9b6e45b53251daccffc3bc5845d51718e1317ba5 100644
--- a/bilby/hyper/model.py
+++ b/bilby/hyper/model.py
@@ -1,4 +1,4 @@
-from ..core.utils import infer_parameters_from_function
+from ..core.utils import infer_args_from_function_except_n_args
 
 
 class Model(object):
@@ -18,10 +18,6 @@ class Model(object):
         self.models = model_functions
 
         self.parameters = dict()
-        for func in self.models:
-            param_keys = infer_parameters_from_function(func)
-            for key in param_keys:
-                self.parameters[key] = None
 
     def prob(self, data, **kwargs):
         probability = 1.0
@@ -31,7 +27,7 @@ class Model(object):
 
     def _get_function_parameters(self, func):
         """If the function is a class method we need to remove more arguments"""
-        param_keys = infer_parameters_from_function(func)
+        param_keys = infer_args_from_function_except_n_args(func, n=0)
         ignore = ['dataset', 'self', 'cls']
         for key in ignore:
             if key in param_keys: