What is Psychology?

Psychology is… The science that studies behavior and the

physiological and cognitive processes that underlie behavior It is empirical

Conclusions are based on direct observations rather than speculation, traditional beliefs, or common sense

Which demands data and documentation…

The Scientific Approach Goals

Measurement and description Understanding and prediction

Creating a hypothesis and then testing it Application and control

Apply info. to everyday events

Steps in the Scientific Process Initial observation or question

Scientist observes something noteworthy and asks a question about it.

WHY? Example: Kitty Genovese incident

Why did no one help?

Steps in an investigation 1. Gather info and formulate a hypothesis

What info already exists? Use info to formulate a hypothesis (specific question

about a phenomenon) Identify variables-anything that can take on two or more

values Ex. Did a diffusion of responsibility occur?

Hypothesis: If multiple bystanders are present, then each bystander’s likelihood of intervening will decrease.

2. Select the method and design a study Experiments (manipulates one or more

variables) Case studies (in-depth investigation of a person) Surveys (collect info via web or paper and relate

to variables of interest) Naturalistic observations (direct observations)

Choose participants Ex. Kitty Genovese incident

Create emergency in a controlled setting Use an experiment to manipulate # of bystanders

present an emergency situation Measure helping

3. Collect the data Use direct observations, questionnaires,

interviews, psychological tests and recordings, and examination of archival records

Ex. split participants into high # of bystander condition or a low # of bystander condition

Run the study

4. Analyze the data and draw conclusions Are there differences between the conditions? How big of a difference? Is it meaningful?

Use statistics to explain the magnitude of differences Helping decreases as the perceived number of

bystanders increase (If hypothesis not supported, revise and retest)

5. Report the findings Communicate and share the findings

Present at conference Poster, paper, presentation

Journal Experts review and critique

Using Experimental Research Manipulate one or more variables under

controlled conditions in order to observe changes in another variable

Only approach to determine cause-effect relationships Independent Variable (IV): factor is manipulated by

experimenter Dependent Variable (DV): factor that is measured by

experimenter and may be influenced by the IV

Experimental Group Group that receives treatment or an “active”

level of the IV

Control Group Group that is not exposed to the treatment or

receives a zero-level of the IV Purpose of control group: provide a standard

of behavior to which the control group can be compared

Extraneous Variables Any variable other that the IV that influences

results

Confounding variables Two variable that are intertwined that make it

unable to determine which one has influenced the DV

Examples of Confounding Variables

Group 1 Group 2 Group 3

IV-Type of

Music

New Age Country Rock

Confounding

Variable -

Volume Level

Low Moderate High

Manipulating Multiple Variables You can measure two or more IV or

measure two or more DV within a single experiment Interested in the effects of expectations and

actual effect of caffeine on task performance Two IV

Expectancy of caffeine: expects vs. doesn’t expect Actual drink: receives caffeine vs. receives none http://www.youtube.com/watch?v=8MS-LvS0aNw&featu

re=relmfu

Advantages/Disadvantages Advantages

Allows for cause-effect conclusions to be drawn

Disadvantages Artificiality of study Can’t be used to examine all scientific questions Ethical and practical issues

When you can’t use the experimental method to address a research question, you can use … Case Studies Naturalistic Observations Survey Research Correlational Research