Observer recorder error as affected by different tasks and different expectancy inducements

Four experiments were designed to investigate the effects of systematic observer/recorder error on experimental results where experimenters had been induced to expect certain results. In the first experiment, experimenters were induced to expect certain outcomes for three different tasks. No observer error nor experimenter-effects were observed. Postexperimental interviews indicated some suspiciousness as well as failure to understand the hypotheses on the part of experimenters. In the second experiment expectancies were induced in observers who did not act as experimenters. No observer effects were noted, and again postexperimental interviews indicated manipulation failure. In the third experiment experimenters were asked to attempt to influence subjects' responses. Three tasks were used, but in two of these tasks observer error was controlled rather than measured. No differences in subjects' responses were noted for any of the measures. However, significant observer/recorder error was noted for both male and female experimenters in the task where such error was measurable. In the fourth experiment experimenters were again asked to influence subjects' responses. For the two tasks used observer error was measured. A predicted Task × Observer Error Interaction was obtained. Again, no differences in subjects' responses were noted.