Forty-Two Rats Were Trained on a Fixed-Interval 1-Minute Operant-Conditioning Schedule

Essay

Forty-two rats were trained on a fixed-interval 1-minute operant-conditioning schedule. On such a schedule, the animal learns to respond after one minute has passed. This is a good test of the animal's perception of time. The 42 rats were divided into two groups. Group 1 was given a drug reputed to distort time perception. Two rats died of causes unrelated to the experiment. The following scores represent performance. Higher scores mean greater time distortion. Analyze with an appropriate nonparametric statistic.
$$\begin{array} { c c } \text { Drug } & \text { No Drug } \\\hline 70 & 63 \\51 & 21 \\37 & 40 \\69 & 61 \\57 & 18 \\42 & 71 \\79 & 48 \\83 & 33 \\70 & 25 \\69 & 76 \\85 & 84 \\91 & 39 \\72 & 41 \\47 & 29 \\68 & 58 \\77 & 60 \\31 & 13 \\27 & 54 \\69 & 26 \\98 & 59 \\95 & \\32 &\end{array}$$