Stillman J A
Percept Psychophys. 1989 Oct;46(4):345-50. doi: 10.3758/bf03204988.
Thresholds for a masked 1-kHz tone were obtained in single sessions from 60 inexperienced listeners. A two-alternative forced-choice procedure was used in conjunction with one of three adaptive psychophysical techniques. These techniques comprised two staircase techniques targeting either 70.7% or 79.4% correct detection (Staircase-71 and Staircase-79), and parameter estimation by sequential testing (PEST), targeting 80% correct detection. Listeners were provided with a rationale for maintaining concentration at weak signal levels. Similar threshold values were obtained from the Staircase-79 and PEST groups in equal numbers of trials. The degree of oscillation in the level of the signal around the value finally chosen as the threshold was comparable for both staircase techniques. Subsequent fixed-level testing did not provide a true indication of the subjects' capabilities. The amount by which percent correct in fixed-level testing differed from expectations based on adaptive testing varied among the techniques. Additional thresholds were obtained in a second session from 30 of the original subjects. Thresholds with both staircase techniques improved by about 1 dB on retest, while thresholds with PEST were constant across sessions. The variability of the data compared well with that from studies involving experienced listeners.
在单次测试中，从60名没有经验的听众那里获得了被掩蔽1千赫纯音的听阈。采用了二选一的强制选择程序，并结合三种自适应心理物理学技术之一。这些技术包括两种针对70.7%或79.4%正确检测率的阶梯技术（阶梯-71和阶梯-79），以及针对80%正确检测率的顺序测试参数估计法（PEST）。向听众说明了在弱信号水平下保持注意力集中的理由。在相同数量的试验中，阶梯-79组和PEST组获得了相似的阈值。两种阶梯技术在最终被选为阈值的值周围信号水平的振荡程度相当。随后的固定水平测试并不能真实反映受试者的能力。固定水平测试中的正确百分比与基于自适应测试的预期值之间的差异程度因技术而异。从最初的60名受试者中的30名在第二次测试中获得了额外的阈值。再次测试时，两种阶梯技术的阈值提高了约1分贝，而PEST技术的阈值在各次测试中保持不变。这些数据的变异性与涉及有经验听众的研究结果相当。
