The Experiment: Hunting for Causes

Ch 1 Sec 6

Pages 26-30

Objectives

• Define experiments- Need this for whole year!• Create An example of an experiment • Formulate a flow chart of variables in a

psychological experiment• List the items for psychological experiment

guidelines

experiments in psychology

• Descriptive studies are nice….HOWEVER• Experimental method is great for cause of

behavior• Experiment allows researcher to Control or

manipulate, the situation being studied• Not just an observer; NOT LIKE naturalistic

observation• Can actively seek cause and effect

Shock Experiment

What do you see?

Ethical Guidelines

• APA has code of ethics• Informed consent- Subjects must be informed

so they can make intelligent decision• Protect physical and mental harm• Animals and Humane treatment

Experimental variables= Looking for relationship

• Ask A question .. Do cigarettes effect driving?• Nicotine in cigarettes improves reaction time• THEREFORE give ½ subjects cigs, half placebo;

then test driving• Independent Variable- changed or manipulated

by researcher• Dependent Variable- Reaction of subject,

behavior…Outcome, depends on I.V.• I.V. cigs, placebo. D.V. driving, wrecks

chapter 1

Experimental and Control Conditions

• Experiments usually require experiment condition AND control condition

• Control Condition- People, subjects, treated exactly like those in ex. Con. HOWEVER not given same treatment or manipulation or stimulus of I.V.

• As a result 2 groups; Experimental group, control group

Experimental/ Control Conditions cont.

• Random assignment- Desire age, gender, socioeconomic difference So give numbers then say odds over here- even over hear.

• F.E. class cards• Placebo- Fake treatment

Experiment effects

• Expectations of subs/researchers can influence study

• Single-blind study- Participants DO NOT KNOW if they are in control group or experimental . group

• Experimenter effects- Tone of voice, facial expressions, posture can effect peoples responses

• Double Blind study- Researcher doesn’t know groups either

Experimenter effectsUnintended changes in subjects’ behavior due to cues inadvertently given by the experimenter.

Strategies for preventing experimenter effects include single- and double-blind studies.

chapter 1

Advantages and Limitations of Experiments

• Cause and effect and Placebo= positive• Negative-• Participants not represent group accurately• Researcher makes the questions• Field Research- Uses descriptive and

experimental methods• F.E. study prejudice in schools and lab

Summary Time!

• Variables• Experiments, groups, conditions • Experimenter effects