How can we reduce some of these effects?

• Conduct your observations as unobtrusively as possible. Try to blend into the setting in order to minimize reactive behavior.
  
  
• Develop a rating form that lists all the behaviors to be observed based on an existing taxonomy or a pilot study that identifies the important variables.
  
  
• Selective perception can be reduced by having observers who are “blind” to the study hypothesis do the ratings.