Display memory decay time governs the way in which the subject gets feedback. There are potentially two extreme conditions:
In the first case there is no memory whatsoever for past performance while in the second case there is total memory.
In this experiment some intermediate cases are chosen. These are determined by a constant a, which we call the display memory decay parameter. The horizontal deflection on the display screen (X), after m intervals, is proportional to the exponentially decaying z-score.
Xm = Sum {exp(-a(m-i)(N1i - n2i)} / sqrt(SUM(exp(-a(m-i))(n1i+n2i)}
where n1i, n2i are the number of pulses on channee 1 and 2 during interval i.
The values of a for the different runs are:
| Part A | Part B | |
|---|---|---|
| short | 0.2878 | 0.6931 |
| long | 0.1336 | 0.2878 |