Abstract: The relationship between the d', β and DL in the theory of signal Detec-tion was investigated in this paper. A detection experiment of weight discrim-ination without the help of vision was made by "yes-no" method. There are2 weight stimuli in which one is 100g as signal, and the other one 108g asnoise. The presentation of stimulus is arranged under 4 different probabilities.The following results have been obtained: 1. There is a negative relationship between the d' and DL. 2. There seems no relationship between the d' and β. 3. The relationship between the β and DL is not fixed, whenβ>1 it ispositive, but it is negative as β<1.

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