Evaluation

• The participants were selected by opportunity sampling


  as the participants were selected opportunistically on the street, unknown factors could affect their behaviour. If someone is rushing to a job interview then they may be less likely to stop and pick up a piece of litter, regardless of who is giving the order.
• The research is culturally bias


  only took place in a street in one city in America. Other cultures might react very differently in the same situation. Results could also differ within different areas of America.
• The study was unethical as participants did not know they were being studied


  field experiment, participants did not know that they were taking part in a research study, therefore they did not give their consent to take part and were deceived. They might also have felt embarrassment at being asked to pick up litter or give someone a dime. Also, they were not debriefed after the experiment.
• There was a gender bias


  all the confederates were male. If the person wearing a uniform had been female than the results might have been very different.
• As it was a field experiment, there was little control over extraneous variables


  researchers were unable to control the weather, if it was raining, it might have affected obedience levels as participants might have wanted to quickly get out of the rain.