Problem:
A researcher conditions rats to fear a tone that was sounded just prior to a brief shock. To measure fear following this conditioning, she records the number of lever presses by each rat in the presence and in the absence of the tone. It was hypothesized that reduced lever pressing in the presence of the tone was evidence for a conditioned fear response in rats. If the researcher tested this hypothesis at a .05 level of significance (two-tailed test), then what is her decision if she computes t = - 2.842 in a sample of 8 rats? Group of answer choices Reject the null hypothesis; there is no evidence for a conditioned fear response. Reject the null hypothesis; there is evidence for a conditioned fear response. Retain the null hypothesis; there is not evidence for a conditioned fear response. Retain the null hypothesis; there is evidence for a conditioned fear response. Need Assignment Help?