___________________________________________________________________________________________________________________ THE HUNGRY MONKEY GAME (dove-hawk paradigm) ___________________________________________________________________________________________________________________ Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC last updated: 01-18-2023 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC Script Copyright © 01-18-2023 Millisecond Software ___________________________________________________________________________________________________________________ BACKGROUND INFO ___________________________________________________________________________________________________________________ This script runs an experiment designed for kids based on the dove-hawk paradigm (aka Game of Chicken)*. The basic premise of the dove-hawk paradigm is that two people compete for the same resources and have to decide to (a) take the resources fast or (b) wait for the opponent's decision. If they decide to take the resource they can either win the resource (=> the other person waited) or experience a devastating loss (=>the other person also went for the resource). If they wait they either don't get the resource (=> the other person went for the resource) or are able to share it (=> the other person also waited). *Reference for Dove-Hawk Paradigm (aka Game of Chicken): http://en.wikipedia.org/wiki/Chicken_(game) ___________________________________________________________________________________________________________________ TASK DESCRIPTION ___________________________________________________________________________________________________________________ In this experiment, kids are asked to collect as many bananas as they can for a hungry monkey named "Charly" while competing with a (computer-generated) "second player", e.g. "Alex"*. In order to decide if they want to a) wait to see what the opponent is doing (=dove behavior) or b) take the bananas right away (=hawk behavior) they have to consider the following rules that determine the outcome of their decisions: 1) If the participant takes the bananas and the opponent waits, the participant gets the full amount of the offered bananas 2) If the opponent takes the bananas and the participant waits, the participant neither wins nor loses any bananas 3) If the opponent and the participant wait, they equally share the bananas (each gets half) 4) If both take the bananas, they each lose double the amount of bananas offered ___________________________________________________________________________________________________________________ DURATION ___________________________________________________________________________________________________________________ the default set-up of the script takes appr. 12 minutes to complete ___________________________________________________________________________________________________________________ DATA FILE INFORMATION ___________________________________________________________________________________________________________________ The default data stored in the data files are: (1) Raw data file: 'dovehawk_raw*.iqdat' (a separate file for each participant) build: The specific Inquisit version used (the 'build') that was run computer.platform: the platform the script was run on (win/mac/ios/android) date, time: date and time script was run subject, group: with the current subject/groupnumber session: with the current session id blockcode, blocknum: the name and number of the current block (built-in Inquisit variable) trialcode, trialnum: the name and number of the currently recorded trial (built-in Inquisit variable) Note: trialnum is a built-in Inquisit variable; it counts all trials run; even those that do not store data to the data file such as feedback trials. Thus, trialnum may not reflect the number of main trials run per block. opponent_name: name of the current opponent p_hawk: probability of hawk-strategy (likelihood that opponent "takes" the bananas) winamount: current amount of bananas that can be won comp_strategy: opponent's decision: 1 = hawk (=take), 0 = dove (=wait) response: the response box that participant clicked p_response: participant's choice: 1 = hawk (take), 0 = dove (=wait) (interpretation of selected response box) latency: time it took participant to make a choice in ms (once the response boxes were presented) outcome: the outcome of the "fight": 1 = opponent wins, 2 = participant wins, 3 = both lose, 4 = compromise p_total: the total sum of bananas won at this time (2) Summary data file: 'dovehawk_summary*.iqdat' (a separate file for each participant) inquisit.version: Inquisit version run computer.platform: the platform the script was run on (win/mac/ios/android) startDate: date script was run startTime: time script was started subjectid: assigned subject id number groupid: assigned group id number sessionid: assigned session id number elapsedTime: time it took to run script (in ms); measured from onset to offset of script completed: 0 = script was not completed (prematurely aborted); 1 = script was completed (all conditions run p_total: the total sum of bananas won ___________________________________________________________________________________________________________________ EXPERIMENTAL SET-UP ___________________________________________________________________________________________________________________ The experiment offers 3 basic blocks that vary the probability with which the computer-generated opponent decides to take bananas (=hawk) or wait (=dove): 1) Mixed Block: p(hawk) = 0.5 2) Hawk: p(hawk) = 0.8 3) Dove: p(hawk) = 0.2 In each of these blocks, participants are presented with 15 trials in which they have to make a dove-hawk decision. The name of the opponent for each block is randomly pulled from a pool of 3 gender-neutral names Note: if trial sequence needs a build-in delay, there are several editable parameter that can be set to accomplish a delay. A second round of the three basic blocks continuously increases the amount of bananas that can be won by 2 (max amount of bananas that can be won = 30, max of bananas that can be lost = 60). ___________________________________________________________________________________________________________________ STIMULI ___________________________________________________________________________________________________________________ provided by Millisecond Software - check under section EDITABLE STIMULI ___________________________________________________________________________________________________________________ INSTRUCTIONS ___________________________________________________________________________________________________________________ provided by Millisecond Software - check under section EDITABLE INSTRUCTIONS ___________________________________________________________________________________________________________________ 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: to build in delays: skipdelay: false = delay trials are run true = delay trials are not run (default) responseboxdelay: delay of the response boxes in ms (default: 0ms) posttrialpause_choice: default = 0 ms delayduration: the duration of the delay trial in ms (default: 5000ms) - runs only if skipdelay = false posttrialpause_feedback: default = 0 ms nextdelay: delay of the 'continue/next' buttons after feedback was given (default: 0ms) to change these variables, also change the corresponding lists under "EDITABLE LISTS": pr_mixed: sets the probability of hawk strategy in the mixed condition, here: 0.5 pr_hawk: sets the probability of hawk strategy in the hawk condition, here: 0.8 pr_dove: sets the probability of hawk strategy in the dove condition, here:0.2