Parts of an ExperimentParts of an Experiment

Population – the type of people that you want to study.

Example: Americans, teenagers, people who pick their noses

Sample – the people you actually use in the experiment.

Generally, the bigger the sample, the “truer” your results

Types of SamplesTypes of Samples

M and M experimentStratified sample – you pick the characteristics

that you want.(better with smaller samples)Random sample – you get what you get and you

don’t get upset.(need to be larger)How to get a random sample?

You got the people, now what?

You got the people, now what?

Put them into groups:Experimental group – they are the ones that you are

going to “do” something to.Control group – the are the ones who we compare

the experiment group to.Placebo group – fake out.

VariableVariable

A variable is a thingIndependent variable – it is what “I” as the

experimenter do to the experimental groupDependent variable – it is what the independent

variable does to the person/animalPlacebo – sugar pill to determine if the

independent variable actually does it or we just think it does.