PEBL Dot Judgment Task: This sample task demonstrates the use of simultaneous interleaved staircase procedures to estimate thresholds.
Designed, loosely, after one described by Damos (1986). As described by Damos, the task is not very interesting. Once you get beyond 10-15 points, you are essentially guessing. Thus, it is modified in order to determine JND thresholds for 10,20,30,40 points, using and interleaved staircase procedure.
numReps <- 50 ##Number of repetitions
 Data Output
Data are saved to:
- dotjudgment\data\dots-X.csv (individual participant trial-by-trial)
- dotjudgment\data\dots-pooled.csv (pooled trial-by-trial)
- data\dots-summary-X.txt (summary stats for each participant)
- data/dots-log.csv (basic log file about participant running)
- data/dots-all.csv. (pooled summary stats--one line per participant)
in the dots-X.csv file, the columns are subnum, block, trial, practice, standard, thresh, side, corr, abstime, and rt
Here, block is the trial block, practice is whether these were practice trials, standard is the number of actual dots on the side with fewer dots, thresh is the current staircase-measured 50% threshold difference, so that standard+thresh is the number of dots on the greater side, side is the side on which the target is on (-1 is left is higher, +1 is right is higher), abstime is the absolute time in ms since the experiment started, rt is the response time of the trial (in ms).
Mueller, S. T. (2011). The PEBL Dot Judgment Task. Computer software retrieved from http://pebl.sf.net/battery.html
Damos, D. L. (1986). Development of a Computer-Based Naval Aviation Selection Test Battery. NAVAL AEROSPACE MEDICAL RESEARCH LAB PENSACOLA FL.