Science Buddies: "Ask an Expert"

For the project about eyewitness accuracy why does the person acting out the scenario have to be unfamiliar with the group of people?

Your help will be muchly appreciated.

thanks!!

Hi,
I think you are refering to this:

https://www.sciencebuddies.org/science- ... p014.shtml
"Materials and Equipment
To do this experiment you will need the following materials and equipment:
* sample group to serve as witnesses,
* a person unfamiliar to the sample group to act out scenario..."


For the experiment as written, the answer is that if the actor is familiar to the group of observers, then your results will be biased by the previous experiences of the observers with the actor. For example, if the actor were your father, you would probably know the answers to many of the eyewitness survey questions (height, weight, gender, clothing, etc) even if you had your eyes closed and ears plugged when he was in the room.

Your question raises an interesting point - you could design a different experiment where one variable is the level of familiarity of the observers with the actor. You could have the actor visit multiple times and see how the accuracy changes, or you could use different actors with different levels of familiarity to the observers. There are lots of possibilities for building a new variation of this experiment.

Good luck with the experiment.

Chris

Thanks i understand it now.

=]

- muchly appreciated

Great. I hope it goes well. Please keep us updated.