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										BOMB RISK ELICITATION TASK
										(dynamic version)

SCRIPT INFO

Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
Date: 06-27-2017
last updated: 07-06-2017 by K.Borchert (katjab@millisecond.com) for Millisecond Software LLC

Script Copyright © 07-06-2017 Millisecond Software


BACKGROUND INFO 

											*Purpose*
This script implements the dynamic (computerized) Bomb Risk Elicitation Task as described in:

Crosetto, P., Filippin, A. (2013). The bomb risk elicitation task. J. Risk
Uncertain. 47 (1), 31–65.

											  *Task*
Participants see a grid of 100 (25) parcels and are told that one of these parcels hides a time bomb.
The parcels are automatically removed, one-by-one (starting with the upper left parcel) until
the participant stops the collection process. The participant earns a predetermined amount of 
money for each parcel removed. However, they can only keep the money if the time bomb is revealed
to be located in one of the uncollected parcels.

Several parameter settings are possible (see section Editable Parameters):
1) the time bomb location can be determined by computer (default) or it can be manually determined by experimenter/participant
(Note: key "I" advances to a trial that accepts manual input of a number)
2) the time bomb can go off immediately once the location has been collected or the location is determined 
after the participant stops the collection process (default)
3) participants can start with a "start capital" or without (start capital is immediately 'lost' when participants decide to play the game -> lost aversion setting)
4) number of parcels: choose btw. 25 or 100 parcels (default)
5) amount of money won per parcel: $0.1 (default)
6) collectionRate:	the rate at which the parcels get collected (default: 1000ms per parcel)
7) number of rounds played: 1 (default; Note: the BRET was originally designed to be a 1-choice task)


DATA FILE INFORMATION: 
The default data stored in the data files are:

(1) Raw data file: 'bombriskelicitationtask_raw*.iqdat' (a separate file for each participant)*

build:							Inquisit build
computer.platform:				the platform the script was run on
date, time, subject, group:		date and time script was run with the current subject/groupnumber 
blockcode, blocknum:			the name and number of the current block
trialcode, trialnum: 			the name and number of the currently recorded trial
									(Note: not all trials that are run might record data; by default data is collected unless /recorddata = false is set for a particular trial/block) 
/bombLocationDrawingMode:		computer: the bomb location is randomly determined by the computer
									(-> list.parcels) (script default)
								manual: the bomb location is manually determined by experimenter
										
/explosionMode:					delayed: the bomb location reveal is delayed until after the collection process is stopped (default)
								immediate: the bomb location is revealed immediately when the bomb has been collected										
									!Note: for (manually) predetermined sequences used for 'immediate' explosions: go to section Editable Lists list.manualBombLocations
							
/nrRounds:						the number of rounds played (default: 1)
									!Note: the BRET was originally designed to be a 1-choice task							
/collectionRate:				the rate at which the parcels get collected (default: 1000ms per parcel)							
/winAmount:						the potential win amount per collected parcel (default: 0.1)										
/startCapital:					stores the amount of money provided as start capital (-> 'loss aversion' treatment).
								The start capital is lost immediately if participants decide to play the game.
									(default: 0 -> participant starts at 0)
/nrParcels:						the number of parcels in the grid (100 vs. 25)									
/bomb:							stores the location (1-100 or 1-25) of the bomb
/parcelsSelected:				counts the number of parcels selected
/roundTotal:					stores the amount of money 'won' for the current round 
/total:							stores the total amount of money won from all rounds
/explosion:						1 = time bomb goes off (parcel collected); 2 = time bomb does NOT go off									
									
response:						the participant's response
correct:						accuracy of response: 1 = correct response; 0 = otherwise
latency: 						the response latency (in ms); measured from: onset of trial

(2) Summary data file: 'bombriskelicitationtask_summary*.iqdat' (a separate file for each participant)*

script.startdate:				date script was run
script.starttime:				time script was started
script.subjectid:				subject id number
script.groupid:					group id number
script.elapsedtime:				time it took to run script (in ms)
computer.platform:				the platform the script was run on
/completed:						0 = script was not completed (prematurely aborted); 1 = script was completed (all conditions run)
/bombLocationDrawingMode:		computer: the bomb location is randomly determined by the computer
									(-> list.parcels) (script default)
								manual: the bomb location is manually determined by experimenter
										
/explosionMode:					delayed: the bomb location reveal is delayed until after the collection process is stopped (default)
								immediate: the bomb location is revealed immediately when the bomb has been collected										
									!Note: for (manually) predetermined sequences used for 'immediate' explosions: go to section Editable Lists list.manualBombLocations
							
/nrRounds:						the number of rounds played (default: 1)
									!Note: the BRET was originally designed to be a 1-choice task							
/collectionRate:				the rate at which the parcels get collected (default: 1000ms per parcel)							
/winAmount:						the potential win amount per collected parcel (default: 0.1)										
/startCapital:					stores the amount of money provided as start capital (-> 'loss aversion' treatment).
								The start capital is lost immediately if participants decide to play the game.
									(default: 0 -> participant starts at 0)
/nrParcels:						the number of parcels in the grid (100 vs. 25)	
									
dependent measures:									
/riskBehavior:					if the number of collected parcels (in the case of multiple rounds: mean number of collected parcels) is less than parcelcount/2, the participant is classified as 'risk averse';
								if it is 'parcelcount/2', the participant is classified as 'risk neutral';
								if it is more than 'parcelcount/2', the participant is classified as 'risk seeker'.
									(Crosetto & Filippin, 2013, p.9)									
/total:							stores the total amount of money won from all rounds
/meanExplosions:				proportion of explosions across rounds							
/meanParcelsCollected:			the mean number of parcels collected across rounds
/bombLocations:					stores the bomb locations of all rounds (in sequence)

* separate data files: to change to one data file for all participants (on Inquisit Lab only), go to section
"DATA" and follow further instructions


EXPERIMENTAL SET-UP

1. Demo: 1 round with no bomb location reveal
2. Testround(s) - by default only 1 round is run
initial presentation of the matrix (press Start)
-> a parcel is removed from the screen at 1parcel/second until Stop is pressed 
(optional: if explosionmode is 'immediate', bombs goes off once the target parcel is collected)
-> bomb reveal 


STIMULI
a 10x10 (5x5) matrix of blue parcels,
the setup is based on the ones by Crosetto & Filippin (2013)

INSTRUCTIONS
provided by Millisecond Software.
The instructions are based on the ones provided by Crosetto & Filippin (2013) and are 
presented in this script in the form of html pages. The html files can be edited directly
with simple text editors such as Notepad (windows) or TextEdit (Mac).


EDITABLE CODE:
check below for (relatively) easily editable parameters, stimuli, instructions etc. 
Keep in mind that you can use this script as a template and therefore always "mess" with the entire code to further customize your experiment.

The parameters you can change are:

/bombLocationDrawingMode:	computer: the bomb location is randomly determined by the computer
								(-> list.parcels) (script default)
							manual: the bomb location is manually determined by experimenter
							!!!Note: key "I" advances to a trial that accepts manual input of a number once experiment is alerted by participant
										
/explosionMode:				delayed: the bomb location reveal is delayed until after the collection process is stopped (default)
							immediate: the bomb location is revealed immediately when the bomb has been collected
										
							!!!Note: for (manually) predetermined sequences used for 'immediate' explosions:
							go to section Editable Lists list.manualBombLocations
										
/startCapital:				stores the amount of money provided as start capital (-> 'loss aversion' treatment).
							The start capital is lost immediately if participants decide to play the game.
							(default: 0 -> participant starts at 0)
										
/winAmount:					the potential win amount per collected parcel (default: 0.1)

/collectionRate:			the rate at which the parcels get collected (default: 1000ms per parcel)

/nrRounds:					the number of rounds played (default: 1)
								!Note: the BRET was originally designed to be a 1-choice task

/nrParcels:					the number of parcels in the grid (100 vs. 25)	(default: 100)
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