What makes a good experiment?. Sampling Techniques 1.Indentify the target population Get a Random Sample – (everyone in the population has the same chance.

What makes a good experiment?

Sampling Techniques

1. Indentify the target population

• Get a Random Sample– (everyone in the

population has the same chance of being chosen).

Grouping your sample…

• Experimental (treatment) group

• Control Group• Placebo Control Group– Placebo Effect

Experimental group gets the IV

Control group gets no IV

Sometimes there is a Placebo group which gets a fake IV (Placebo)

http://www.youtube.com/watch?v=yfRVCaA5o18

Types of Experiments

Laboratory Experiments• Maximizes control over

the variables.• Easier to show reliability

and sometimes validityWhat is the weakness of a

lab experiment?• Artificial results• Hawthorne or screw-

you effect

Observing the effects of a scary movie in a lab.

Types of Experiments

Field Experiments• Try to control the

variables out in the real world.

What are its strengths?• Improves ecological

validityWhat are its weaknesses?• More confounding

variables

Observing the effects of a scary movie in the home.

Types of Experiments

Quasi• The IV occurs naturally and

cannot be controlled.• Like the introduction of the

iphone and Samsung Android.• Very little control over the

variables.• Like studying whether people

that drink more pick certain fraternities.

• But at least its real.

How to read a research article:

1. Abstract2. Literature Review3. Methodology4. Results5. Discussion6. Conclusion7. Sources