diff --git a/py/20200221_experiment_scheduling.py b/py/20200221_experiment_scheduling.py
index 0916bb8..09b439a 100644
--- a/py/20200221_experiment_scheduling.py
+++ b/py/20200221_experiment_scheduling.py
@@ -15,81 +15,94 @@
 sns.set_style('white')
 # experiment duration in minutes
 session_duration = 60
+game_duration = 45
 n_subjects = 2
 n_sessions = 12
 duration_per_question = .1666667 # minutes (~10sec)
-questionnaires = {
-  "study_level": {
-    "xcit_demographics": 20,
-    "aiss": 20,
-    "arces": 12,
-    "asrs": 18,
-    "avg2019": 16,
-    "bfi_2": 60,
-    "bisbas": 24,
-    "bis11": 12,
-    "cfq": 25,
-    "cfs": 12,
-    "dyslexia": 15,
-    "ehi_sf": 4,
-    "grit12": 12,
-    "i_panas_sf": 10,
-    "ipaq_sf": 7,
-    "maas": 15,
-    "mfs": 12,
-    "mw": 8,
-    "mwq": 5,
-    "ncs_6": 6,
-    "nfc": 18,
-    "psqi": 9,
-    "rei": 40,
-    "sci": 8,
-    "sqs": 28,
-    "upps_sf": 20,
-    "webexec": 12,
-    "who5": 5,
-    "whoqol": 26,
-    "xcit_poststudy_debrief": 20 # only in session 12
-  },
-  "session_level": {
-  'nasa_tlx': 6, # after game
-  "xcit_postgame_debrief": 15 #after game
-  }
+
+prestudy_tasks = [
+  "xcit_demographics"
+]
+
+postgame_tasks = [
+  "nasa_tlx",
+  "xcit_postgame_debrief"
+]
+
+poststudy_tasks = [
+  "xcit_poststudy_debrief"
+]
+
+n_questions = {
+  "xcit_demographics": 20,
+  "aiss": 20,
+  "arces": 12,
+  "asrs": 18,
+  "avg2019": 16,
+  "bfi_2_par1": 30,
+  "bfi_2_part2": 30,
+  "bisbas": 24,
+  "bis11": 12,
+  "cfq": 25,
+  "cfs": 12,
+  "dyslexia": 15,
+  "ehi_sf": 4,
+  "grit12": 12,
+  "i_panas_sf": 10,
+  "ipaq_sf": 7,
+  "maas": 15,
+  "mfs": 12,
+  "mw": 8,
+  "mwq": 5,
+  "ncs_6": 6,
+  "nfc": 18,
+  "psqi": 9,
+  "rei": 40,
+  "sci": 8,
+  "sqs": 28,
+  "upps_sf": 20,
+  "webexec": 12,
+  "who5": 5,
+  "whoqol": 26,
+  "xcit_poststudy_debrief": 20,
+  "nasa_tlx": 6,
+  "xcit_postgame_debrief": 15
 }
 
+
+# 1. define the study
 s = Scenario('Prolific500', horizon=session_duration)
-
-sessions = s.Resources('Session', num=n_sessions)
+# 2. sessions
+sessions = s.Resources('Session', num = n_sessions)
 
 
-# one-time questionnaires
-pregame_tasks = []
-for q in questionnaires['study_level'].keys():
-  n_questions = questionnaires['study_level'].get(q, 0)
-  duration = ceil(n_questions * duration_per_question)
+# 2. games
+games = s.Tasks('Game',length=game_duration, num=n_sessions, is_group=False)
+games += alt(sessions)
+
+# questionnaires
+for q in n_questions.keys():
+  n = n_questions.get(q, 0)
+  duration = ceil(n * duration_per_question)
   task = s.Task(q, length= duration, delay_cost=1)
-  task += alt(sessions)
-  # not really a pregame task
-  # pregame_tasks.append(questionnaire)
+  if q in poststudy_tasks:
+    print(q, 1)
+    task += sessions[-1]
+    s += games < task
+  elif q in prestudy_tasks:
+    print(q, 2)
+    task += sessions[0]
+    s += task < games
+  elif q in postgame_tasks:
+    print(q, 3)
+    task += sessions
+    s += games < task
+  else:
+    print(q, 4)
+    task += alt(sessions)
 
-# game
-games = s.Task('Game',length=45, delay_cost=1, is_group=False)
-games += sessions
+print(s.tasks)
 
-# post-tasks
-postgame_tasks = []
-for q in questionnaires['session_level'].keys():
-  n_questions = questionnaires['session_level'].get(q, 0)
-  duration = ceil(n_questions * duration_per_question)
-  task = s.Task(q, length= duration, delay_cost=1)
-  task += sessions
-  postgame_tasks.append(task)
-
-# add constraints on precedences
-#s += pregame_tasks < games
-s += games < postgame_tasks
-
-# compute and print session schedules
 solvers.mip.solve(s)
 print(s.solution())