RE: Creating Sequence of Explosion points

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RE: Creating Sequence of Explosion points

Creating Sequence of Explosion points

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Brainsrule	Brainsrule posted 8 Years Ago Topic Details Share Topic
Group: Forum Members Posts: 9, Visits: 45	Hello, I'm interested in administering the BART-Y twice to adolescent subjects, and as such I have to change the sequence of explosion points, but still make sure they fit the criteria in Lejuez et al, 2007 : Reliability and validity of the youth version of the Balloon Analogue Risk Task (BART-Y) in the assessment of risk-taking behavior among inner-city adolescents. From the paper: "The BART–Y involved inflating a computer-generated balloon. Each pump is worth 1 point, but if a balloon is pumped past its explosion point, then all points accrued for that balloon are lost.The probability that any particular balloon will explode is 1/128 for the first pump, 1/127 for the second,and so on until the 128th pump at which point the probability is 1/1. According to this algorithm, explosion values form a normal distribution around 64 pumps(see Lejuez et al., 2002, for further details). To determine the actual explosion point sequence to be used in the study, we generated a sequence of 30 explosion points using this algorithm, repeating this approach until a sequence was generated that resulted in an average explosion point across balloons of 64 pumps. Because of the differing range of explosion points from balloon to balloon, many commonly used forms of reliability such as internal consistency could not be calculated. To provide split-half reliability across the task, we further repeated the algorithm noted previously until the first 15 balloons and the second set of 15 balloons both evidenced an explosion point of 64 pumps. This was necessary to ensure equivalence in the range of possible responses across balloons when comparing responding in the first half and second half of the task. The first sequence of 30 explosion points generated that met this criterion was selected for use with each participant to ensure that results were not due to sequence effects across participants." While I can use an outside script to make a sequence that fits these parameters, I was wondering if there was any official sequence generator or second BART-Y sequence available for me to use. Thank you
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Dave	Dave posted 8 Years Ago ANSWER Post Details Share Post
Group: Administrators Posts: 13K, Visits: 105K	+x Brainsrule - Tuesday, March 28, 2017 Hello, I'm interested in administering the BART-Y twice to adolescent subjects, and as such I have to change the sequence of explosion points, but still make sure they fit the criteria in Lejuez et al, 2007 : Reliability and validity of the youth version of the Balloon Analogue Risk Task (BART-Y) in the assessment of risk-taking behavior among inner-city adolescents. From the paper: "The BART–Y involved inflating a computer-generated balloon. Each pump is worth 1 point, but if a balloon is pumped past its explosion point, then all points accrued for that balloon are lost.The probability that any particular balloon will explode is 1/128 for the first pump, 1/127 for the second,and so on until the 128th pump at which point the probability is 1/1. According to this algorithm, explosion values form a normal distribution around 64 pumps(see Lejuez et al., 2002, for further details). To determine the actual explosion point sequence to be used in the study, we generated a sequence of 30 explosion points using this algorithm, repeating this approach until a sequence was generated that resulted in an average explosion point across balloons of 64 pumps. Because of the differing range of explosion points from balloon to balloon, many commonly used forms of reliability such as internal consistency could not be calculated. To provide split-half reliability across the task, we further repeated the algorithm noted previously until the first 15 balloons and the second set of 15 balloons both evidenced an explosion point of 64 pumps. This was necessary to ensure equivalence in the range of possible responses across balloons when comparing responding in the first half and second half of the task. The first sequence of 30 explosion points generated that met this criterion was selected for use with each participant to ensure that results were not due to sequence effects across participants." While I can use an outside script to make a sequence that fits these parameters, I was wondering if there was any official sequence generator or second BART-Y sequence available for me to use. Thank you I am not aware of an official sequence generator, so constructing a conforming sequence either by hand or with the aid of external software (e.g. an R or Python script or the like) would be the way to go. The BART-Y implementation at https://www.millisecond.com/download/library/bart/ includes the original explosion point sequence (kindly shared by Dr. Lejuez and colleagues). A very easy way to get a 2nd comparable sequence might be to simply reverse the two halves.
	Reply Like 36