Two findings are of interest in Figure 3. First, there seems to be little effect of using- either a more or a less concentrated standard. The most interesting result is that there appears to be a progressive loss of memory between the I-min group and the 5-7-min group. Only two errors were committed at the I.O-min interval, whereas 7 of the 10 judgments at the longer interval were incorrect. Of the nine errors in judgment overall, eight were made to the more dilute concentrations. Again, this result is consistent with a model of memory in which a stimulus of a given intensity "fades" to the same qualitative percept, but one of lower intensity.