diff --git a/docker-compose.yml b/docker-compose.yml
index 3649269..54d295a 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -30,6 +30,7 @@ services:
     volumes:
       - ./common:/app/common
       - ./test:/app/test
+      - ./save:/app/save
     container_name: 3lips-event
 
   cesium-apache:
diff --git a/event/algorithm/associator/AdsbAssociator.py b/event/algorithm/associator/AdsbAssociator.py
index 1772a18..ff21c4f 100644
--- a/event/algorithm/associator/AdsbAssociator.py
+++ b/event/algorithm/associator/AdsbAssociator.py
@@ -25,12 +25,13 @@ class AdsbAssociator:
         @brief Constructor for the AdsbAssociator class.
         """
 
-    def process(self, radar_list, radar_data):
+    def process(self, radar_list, radar_data, timestamp):
 
         """
         @brief Associate detections from 2+ radars.
         @param radar_list (list): List of radars to associate.
         @param radar_data (dict): Radar data for list of radars.
+        @param timestamp (int): Timestamp to compute delays at (ms).
         @return dict: Associated detections by [hex][radar].
         """
 
@@ -60,7 +61,8 @@ class AdsbAssociator:
 
                 # associate radar and truth
                 assoc_detections_radar.append(self.process_1_radar(
-                  radar, radar_data[radar]["detection"], adsb_detections))
+                  radar, radar_data[radar]["detection"], 
+                  adsb_detections, timestamp))
 
         # associate detections between radars
         output = {}
@@ -74,7 +76,7 @@ class AdsbAssociator:
 
         return output
 
-    def process_1_radar(self, radar, radar_detections, adsb_detections):
+    def process_1_radar(self, radar, radar_detections, adsb_detections, timestamp):
 
         """
         @brief Associate detections between 1 radar/truth pair.
@@ -94,6 +96,11 @@ class AdsbAssociator:
 
                 if 'delay' in adsb_detections[aircraft] and len(radar_detections['delay']) >= 1:
 
+                    # extrapolate delay/Doppler to current time
+                    # delta_t = (timestamp - adsb_detections[aircraft]['timestamp'])/1000
+                    # delay = 1000*adsb_detections[aircraft]['delay'] + \
+                      
+
                     # distance from aircraft to all detections
                     closest_point, distance = self.closest_point(
                       adsb_detections[aircraft]['delay'], 
@@ -107,7 +114,8 @@ class AdsbAssociator:
                         assoc_detections[aircraft] = {
                           'radar': radar,
                           'delay': closest_point[0],
-                          'doppler': closest_point[1]
+                          'doppler': closest_point[1],
+                          'timestamp': adsb_detections[aircraft]['timestamp']
                         }
 
         return assoc_detections
diff --git a/event/algorithm/truth/AdsbTruth.py b/event/algorithm/truth/AdsbTruth.py
index 9cf5159..f3faca3 100644
--- a/event/algorithm/truth/AdsbTruth.py
+++ b/event/algorithm/truth/AdsbTruth.py
@@ -4,7 +4,6 @@
 """
 
 import requests
-import math
 
 class AdsbTruth:
 
diff --git a/event/event.py b/event/event.py
index 146bd08..79e76c7 100644
--- a/event/event.py
+++ b/event/event.py
@@ -33,10 +33,12 @@ ellipseParametric = EllipseParametric()
 ellipsoidParametric = EllipsoidParametric()
 sphericalIntersection = SphericalIntersection()
 adsbTruth = AdsbTruth(5)
+save = True
+saveFile = '/app/save/' + str(int(time.time())) + '.ndjson'
 
 async def event():
 
-    global api
+    global api, save
     timestamp = int(time.time()*1000)
     api_event = copy.copy(api)
 
@@ -91,7 +93,6 @@ async def event():
     adsb_urls = list(set(adsb_urls))
     for url in adsb_urls:
       truth_adsb[url] = adsbTruth.process(url)
-    print(truth_adsb, flush=True)
 
     # main processing
     for item in api_event:
@@ -122,7 +123,7 @@ async def event():
         return
 
       # processing
-      associated_dets = associator.process(item["server"], radar_dict_item)
+      associated_dets = associator.process(item["server"], radar_dict_item, timestamp)
       associated_dets_3_radars = {
         key: value
         for key, value in associated_dets.items()
@@ -181,6 +182,10 @@ async def event():
     # update API
     api = api_event
 
+    # save to file
+    if save:
+      append_api_to_file(api)
+
 
 # event loop
 async def main():
@@ -189,6 +194,11 @@ async def main():
         await event()
         await asyncio.sleep(1)
 
+def append_api_to_file(api_object, filename=saveFile):
+    with open(filename, 'a') as json_file:
+        json.dump(api_object, json_file)
+        json_file.write('\n')
+
 def short_hash(input_string, length=10):
 
     hash_object = hashlib.sha256(input_string.encode())
diff --git a/script/README.md b/script/README.md
new file mode 100644
index 0000000..7647b47
--- /dev/null
+++ b/script/README.md
@@ -0,0 +1,5 @@
+This folder is for post-processing scripts on API data.
+
+## Scripts
+
+- TODO
\ No newline at end of file
diff --git a/script/plot_accuracy.py b/script/plot_accuracy.py
new file mode 100644
index 0000000..7d846aa
--- /dev/null
+++ b/script/plot_accuracy.py
@@ -0,0 +1,33 @@
+import argparse
+import json
+from datetime import datetime
+
+def parse_posix_time(value):
+    try:
+        return int(value)
+    except ValueError:
+        raise argparse.ArgumentTypeError("Invalid POSIX time format")
+
+def parse_command_line_arguments():
+    parser = argparse.ArgumentParser(description="Process command line arguments.")
+    
+    parser.add_argument("json_string", type=str, help="Input JSON string")
+    parser.add_argument("target_name", type=str, help="Target name")
+    parser.add_argument("--start_time", type=parse_posix_time, help="Optional start time in POSIX seconds")
+    parser.add_argument("--stop_time", type=parse_posix_time, help="Optional stop time in POSIX seconds")
+
+    return parser.parse_args()
+
+def main():
+  
+    args = parse_command_line_arguments()
+    json_data = json.loads(args.json_string)
+    start_time = args.start_time if args.start_time else None
+    stop_time = args.stop_time if args.stop_time else None
+    print("JSON String:", json_data)
+    print("Target Name:", args.target_name)
+    print("Start Time:", start_time)
+    print("Stop Time:", stop_time)
+
+if __name__ == "__main__":
+    main()