Randomise, but force 1st item per talker to be a filler

Comments

• JanV

  February 2018 edited February 2018

  Hello,

  I haven't fully implemented the following solution in OpenSesame yet, but this Python code generates lists that satisfy the constraint (see OP):

  # This script generates a pseudorandom order of stimuli.
  
  # We need the shuffle function from the random library.
  from random import shuffle
  
  item_list =     [("S1", "A", "filler"),
                   ("S2", "A", "filler"),
                   ("S3", "B", "filler"),
                   ("S4", "B", "filler"),
                   ("S5", "C", "filler"),
                   ("S6", "C", "filler"),
                   ("S7", "A", "target"),
                   ("S8", "A", "target"),
                   ("S9", "B", "target"),
                   ("S10", "B", "target"),
                   ("S11", "C", "target"),
                   ("S12", "C", "target")]
  
  # Restrictions on randomisation:
  # - The first stimulus for each talker (second column) needs to be a filler.
  
  # Pick the first stimulus. This needs to be a filler.
  items_notpicked = item_list
  
  # Only retain the stimuli that may be picked, viz., filler items
  under_consideration = [row for row in items_notpicked if 'filler' in row[2]]
  # Shuffle these and take the first item
  shuffle(under_consideration)
  items_picked = [under_consideration[0]]
  
  # Remove the items picked from the available items, i.e., only
  # retain a row if it doesn't contain the sentenceID.
  sentences_selected = [i[0] for i in items_picked]
  talkers_selected = [i[1] for i in items_picked]
  items_notpicked = [i for i in items_notpicked if not i[0] in sentences_selected]
  
  for items in range(len(items_notpicked)):
  # only consider filler items or sentences from talkers already selected
      under_consideration = [row for row in items_notpicked if ('filler' in row[2]) or (row[1] in talkers_selected)]
  # shuffle, take the first one, append to item list
      shuffle(under_consideration)
      items_picked += [under_consideration[0]]
  # update sentence and talker lists
      sentences_selected = [i[0] for i in items_picked]
      talkers_selected = [i[1] for i in items_picked]
      items_notpicked = [i for i in items_notpicked if not i[0] in sentences_selected]
  

  A couple of runs produced lists such as these:

  [('S5', 'C', 'filler'),
   ('S3', 'B', 'filler'),
   ('S9', 'B', 'target'),
   ('S11', 'C', 'target'),
   ('S4', 'B', 'filler'),
   ('S6', 'C', 'filler'),
   ('S12', 'C', 'target'),
   ('S10', 'B', 'target'),
   ('S1', 'A', 'filler'),
   ('S8', 'A', 'target'),
   ('S7', 'A', 'target'),
   ('S2', 'A', 'filler')]
  
  [('S5', 'C', 'filler'),
   ('S2', 'A', 'filler'),
   ('S4', 'B', 'filler'),
   ('S1', 'A', 'filler'),
   ('S12', 'C', 'target'),
   ('S9', 'B', 'target'),
   ('S8', 'A', 'target'),
   ('S11', 'C', 'target'),
   ('S7', 'A', 'target'),
   ('S10', 'B', 'target'),
   ('S3', 'B', 'filler'),
   ('S6', 'C', 'filler')]
  
  [('S6', 'C', 'filler'),
   ('S12', 'C', 'target'),
   ('S4', 'B', 'filler'),
   ('S5', 'C', 'filler'),
   ('S9', 'B', 'target'),
   ('S11', 'C', 'target'),
   ('S2', 'A', 'filler'),
   ('S3', 'B', 'filler'),
   ('S1', 'A', 'filler'),
   ('S10', 'B', 'target'),
   ('S8', 'A', 'target'),
   ('S7', 'A', 'target')]
  
• JanV

  February 2018

  Quick follow-up:At the end of the inline script, I've now added

  global sentences
  items_picked.reverse() # the "pop" method used later works from the back to the front,so just reverse the list here
  sentences = [i[0] for i in items_picked]
  global talkers
  talkers = [i[1] for i in items_picked]
  

  Then I used an inline script before the trial presentation with the following content:

  global sentences
  current_sentence = sentences.pop()
  global talkers
  current_talker = talkers.pop()
  
  exp.set("my_sentence", current_sentence)
  exp.set("my_talker", current_talker)
  

  my_sentence and my_talker can then be used in the trial's sketchpad.

  This seems to do the trick. Hopefully this is useful to other users. Thanks again for developing OpenSesame!
• eduard

  February 2018

  Hi Jan,

  nice that you sorted things out yourself. I haven't looked at your code in detail, but just a few small remarks.

  1) It shouldn't be necessary to declare your variables as globals. All the inline_scripts share a common workspace

  2) In a comment you say: # the "pop" method used later works from the back to the front,so just reverse the list here. Actually, you can specify which item should be popped from a list. The default value is -1 I believe, but if you pass 0 it will pop from the beginning.

  3) exp.set("my_sentence", current_sentence) can be replaces with var.my_sentence = current_sentence

  Hope this is a little useful to you.

  Good luck,

  Eduard

  
• JanV

  February 2018

  Very much so, thank you!