diff --git a/analytics/analytics/analytic_unit_worker.py b/analytics/analytics/analytic_unit_worker.py
index 7cddfe1..2414e2f 100644
--- a/analytics/analytics/analytic_unit_worker.py
+++ b/analytics/analytics/analytic_unit_worker.py
@@ -57,14 +57,7 @@ class AnalyticUnitWorker:
           'lastDetectionTime': None
         }
 
-        chunks = []
-        # XXX: get_chunks(data, chunk_size) == get_intersected_chunks(data, 0, chunk_size)
-        if self._detector.is_detection_intersected():
-            chunks = get_intersected_chunks(data, chunk_intersection, chunk_size)
-        else:
-            chunks = get_chunks(data, chunk_size)
-
-        for chunk in chunks:
+        for chunk in get_intersected_chunks(data, chunk_intersection, chunk_size):
             await asyncio.sleep(0)
             chunk_dataframe = prepare_data(chunk)
             detected = self._detector.detect(chunk_dataframe, cache)
@@ -93,7 +86,7 @@ class AnalyticUnitWorker:
             self.__append_detection_result(detection_result, detected)
         
         detection_result['segments'] = self._detector.get_intersections(detection_result['segments'])
-        
+
         if detection_result['lastDetectionTime'] is None:
             return None
         else:
diff --git a/analytics/analytics/detectors/anomaly_detector.py b/analytics/analytics/detectors/anomaly_detector.py
index 704907a..400ea3a 100644
--- a/analytics/analytics/detectors/anomaly_detector.py
+++ b/analytics/analytics/detectors/anomaly_detector.py
@@ -7,7 +7,6 @@ from analytic_types.data_bucket import DataBucket
 from detectors import Detector
 from models import ModelCache
 import utils
-from analytic_types import AnalyticUnitId
 
 MAX_DEPENDENCY_LEVEL = 100
 MIN_DEPENDENCY_FACTOR = 0.1
@@ -16,8 +15,7 @@ logger = logging.getLogger('ANOMALY_DETECTOR')
 
 class AnomalyDetector(Detector):
 
-    def __init__(self, analytic_unit_id: AnalyticUnitId):
-        self.analytic_unit_id = analytic_unit_id
+    def __init__(self, *args, **kwargs):
         self.bucket = DataBucket()
 
     def train(self, dataframe: pd.DataFrame, payload: Union[list, dict], cache: Optional[ModelCache]) -> ModelCache:
@@ -30,10 +28,7 @@ class AnomalyDetector(Detector):
 
     def detect(self, dataframe: pd.DataFrame, cache: Optional[ModelCache]) -> dict:
         data = dataframe['value']
-        alpha = cache['alpha']
-        confidence = cache['confidence']
-
-        last_value = None
+        last_values = None
         if cache is not None:
             last_values = cache.get('last_values')
 
@@ -60,23 +55,14 @@ class AnomalyDetector(Detector):
         }
 
     def consume_data(self, data: pd.DataFrame, cache: Optional[ModelCache]) -> Optional[dict]:
-        if cache is None:
-            msg = f'consume_data get invalid cache {cache} for task {self.analytic_unit_id}'
-            logging.debug(msg)
-            raise ValueError(msg)
-
-        data_without_nan = data.dropna()
-
-        if len(data_without_nan) == 0:
-            return None
-
-        self.bucket.receive_data(data_without_nan)
-
-        if len(self.bucket.data) >= self.get_window_size(cache):
-            self.detect(self.bucket, cache)
+        self.detect(data, cache)
 
 
     def get_window_size(self, cache: Optional[ModelCache]) -> int:
+        '''
+        get the number of values that will affect the next value
+        '''
+
         if cache is None:
             raise ValueError('anomaly detector got None cache')
         
@@ -90,6 +76,3 @@ class AnomalyDetector(Detector):
         segments = utils.merge_intersecting_intervals(segments)
         segments = [{'from': segment[0], 'to': segment[1]} for segment in segments]
         return segments
-
-    def is_detection_intersected(self) -> bool:
-        return False
diff --git a/analytics/analytics/detectors/detector.py b/analytics/analytics/detectors/detector.py
index b0f891b..def7c3c 100644
--- a/analytics/analytics/detectors/detector.py
+++ b/analytics/analytics/detectors/detector.py
@@ -28,6 +28,3 @@ class Detector(ABC):
     @abstractmethod
     def get_intersections(self, segments: List[dict]) -> List[dict]:
         pass
-
-    def is_detection_intersected(self) -> bool:
-        return True