diff --git a/type_infer/api.py b/type_infer/api.py
index cffcc4d..846541a 100644
--- a/type_infer/api.py
+++ b/type_infer/api.py
@@ -18,10 +18,22 @@ def infer_types(
     data : pd.DataFrame
         The input dataset for which we want to infer data type information.
     """
-    if config is None or 'engine' not in config:
+    # Set global defaults if missing
+    if config is None:
         config = {'engine': 'rule_based', 'pct_invalid': 2, 'seed': 420, 'mp_cutoff': 1e4}
+    elif 'engine' not in config:
+        config['engine'] = 'rule_based'
+
+    if 'pct_invalid' not in config:
+        config['pct_invalid'] = 2
+
+    if 'seed' not in config:
+        config['seed'] = 420
 
     if config['engine'] == ENGINES.RULE_BASED:
+        if 'mp_cutoff' not in config:
+            config['mp_cutoff'] = 1e4
+
         engine = RuleBasedEngine(config)
         return engine.infer(data)
     else: