During WWII, an investigator attempted to examine the hypothesis that punishment is more effective than reward for training people. The task she picked to test this hypothesis was the identification of enemy and friendly airplanes. She had participants sit in front of what appeared to be a radar screen as the silhouettes of enemy and friendly airplanes were flashed on the screen in very short exposures (1 second). As each silhouette appeared, the participant had to respond by pressing one of two buttons – one was marked “enemy” and the other was marked “friendly.” Each person participated in the experiment for two hours on five consecutive days. On the first day, after each stimulus, the participants were told if they had been right or wrong on their identifications. Starting on the second day, the participants were randomly assigned to one of two groups. In Group A, the participants were given ten cents after each correct identification but were not punished for a wrong identification. In Group B, each participant received an electric shock after each wrong identification but received nothing for a correct identification. This procedure continued for days three and four. The fifth day was considered the test day, and the participants followed the same procedure except that no reward, no punishment or no information was given to them. The number of correct identifications per 100 silhouettes was considered the test of the effectiveness of each training method. As expected, there was some loss of participants over the five-day period: about five percent of the Group A people and about 35 percent of the Group B people dropped-out by the fifth day. The data from these people was discarded. The results indicated that on the 100 trials given to each participant on the fifth day, the mean number of correct identifications for Group A was 80, and the mean for Group B was 92. The difference between the means was statistically reliable. The experimenter concluded that the hypothesis was correct and suggested that all training programs be based on punishment.