diff --git a/skllm/models/_base/classifier.py b/skllm/models/_base/classifier.py
index 757457c..46138c7 100644
--- a/skllm/models/_base/classifier.py
+++ b/skllm/models/_base/classifier.py
@@ -222,13 +222,14 @@ def predict(self, X: Union[np.ndarray, pd.Series, List[str]]):
 
         Returns
         -------
-        List[str]
+        np.ndarray
+            The predicted classes as a numpy array.
         """
         X = _to_numpy(X)
         predictions = []
         for i in tqdm(range(len(X))):
             predictions.append(self._predict_single(X[i]))
-        return predictions
+        return np.array(predictions)
 
     def _get_unique_targets(self, y: Any):
         labels = self._extract_labels(y)
@@ -351,6 +352,7 @@ def __init__(
         memory_index: Optional[IndexConstructor] = None,
         vectorizer: _BaseVectorizer = None,
         prompt_template: Optional[str] = None,
+        metric="euclidean",
     ):
         super().__init__(
             model=model,
@@ -360,6 +362,7 @@ def __init__(
         self.vectorizer = vectorizer
         self.memory_index = memory_index
         self.n_examples = n_examples
+        self.metric = metric
         if isinstance(self, MultiLabelMixin):
             raise TypeError("Multi-label classification is not supported")
 
@@ -402,7 +405,7 @@ def fit(
                 index = self.memory_index()
                 index.dim = embeddings.shape[1]
             else:
-                index = SklearnMemoryIndex(embeddings.shape[1])
+                index = SklearnMemoryIndex(embeddings.shape[1], metric=self.metric)
             for embedding in embeddings:
                 index.add(embedding)
             index.build()
diff --git a/skllm/models/gpt/classification/few_shot.py b/skllm/models/gpt/classification/few_shot.py
index b3a9cb0..a3a71c6 100644
--- a/skllm/models/gpt/classification/few_shot.py
+++ b/skllm/models/gpt/classification/few_shot.py
@@ -100,6 +100,7 @@ def __init__(
         n_examples: int = 3,
         memory_index: Optional[IndexConstructor] = None,
         vectorizer: Optional[BaseVectorizer] = None,
+        metric: Optional[str] = "euclidean",
         **kwargs,
     ):
         """
@@ -124,6 +125,8 @@ def __init__(
             custom memory index, for details check `skllm.memory` submodule, by default None
         vectorizer : Optional[BaseVectorizer], optional
             scikit-llm vectorizer; if None, `GPTVectorizer` is used, by default None
+        metric : Optional[str], optional
+            metric used for similarity search, by default "euclidean"
         """
         if vectorizer is None:
             vectorizer = GPTVectorizer(model="text-embedding-ada-002")
@@ -134,5 +137,6 @@ def __init__(
             n_examples=n_examples,
             memory_index=memory_index,
             vectorizer=vectorizer,
+            metric=metric,
         )
         self._set_keys(key, org)