chapter 1 (cont) psychology & science. research method l tool for answering questions l 3 types...

Chapter 1 (con’t)Psychology & Science

Research Method

Tool for answering questions 3 Types

Survey Case study Experiment

Research Method #1 - Surveys

Asking many individuals to answer a fixed set of questions Advantages

Obtain information from a large group quickly Compare answers from different groups (age, SES, culture)

Disadvantages Responses may be influenced by

phrasing of the question who asks the question

People may not answer truthfully

Research Method #2 - Case Study

In-depth analysis of a person’s thoughts, feelings, beliefs, or behaviors

Advantage Provides rich, descriptive detail

Disadvantage Bias & error related to testimonials

Testimonial

Statement in support of a particular viewpoint based on detailed observations of an individual’s personal experience

Problems with Testimonials Biased personal beliefs Self-fulfilling prophecy Placebos & placebo effects

Statistical Procedure - Correlation

A relationship/association between 2 or more events Advantage

Study variables as they are Disadvantage

Can’t determine cause-and-effect relationships

Correlation Coefficient

Numerical measure of the strength of the relationship 2 Areas to consider

Size ranges from 0 to +/- 1.00

Sign (positive or negative) indicates the direction of association

5 Types of Correlation Coefficients

Perfect Positive Correlation (+1.00) Increase in 1 event is matched by an equal increase in a 2nd

event Positive Correlation

As one event tends to increase, the 2nd event tends to increase Zero Correlation

No relationship between the occurrence of one event and the occurrence of a 2nd event

Perfect Negative Correlation (-1.00) Increase in 1 event is matched by an equal decrease in a 2nd

event Negative Correlation

As one event tends to increase, the 2nd event tends to decrease

Research Method #3 - Experiment

Following rules and guidelines that minimize the possibility of error and bias in order to identify cause-and-effect relationships

Advantages Can identify cause-and-effect relationships Minimizes error and bias

Conducting Experiments - 7 Rules to Reduce Error & Bias

Rule 1: Ask a question in the form of a hypothesis Hypothesis = educated guess

Rule 2: Identify the Independent Variable (IV) & Dependent Variable (DV) IV = Treatment DV = Outcome measure

Source: Long Beach, CA. United School District, 1993-1994 versus 1994-1995.

Rule 3: Choose subjects who are representative of the population by using random selection Random selection

each subject has an equal chance of being selected to participate

Conducting Experiments - 7 Rules to Reduce Error & Bias

Rule 4: Randomly assign subjects to experimental and control groups Experimental group

receives the treatment Control group

does not receive the treatment

Conducting Experiments - 7 Rules to Reduce Error & Bias

Rule 5: Manipulate the IV by administering the treatment to the experimental group Double blind procedure

neither the experimenter nor the subject knows which group is receiving the treatment

Conducting Experiments - 7 Rules to Reduce Error & Bias

Rule 6: Measure effect of the IV on the DV

Rule 7: Analyze results using statistical procedures Statistical procedures are used to determine whether observed

differences in the DV are due to the IV or to chance

Conducting Experiments - 7 Rules to Reduce Error & Bias

Placebos & Placebo Effects

Placebo Treatment that resembles medical therapy, but has no medical

effects Example

taking a sugar pill Placebo Effect

Change in the patient’s illness that is attributable to an imagined treatment

Example taking a sugar pill alleviates patients’ symptoms

Research Method #4: Naturalistic Observation

Allows you to view psychological phenomenon in its naturally occurring environment

Researcher does not have to attempt to control or change the situation

Problem: Own biases may influence what is seen!

Research Concerns

Code of Ethics Developed by APA Specifies the researchers’ responsibilities & participants’ rights

Deception Must satisfy the APA’s code of ethics Sometimes used to control for subjects’ expectations

Debriefing Explaining the purpose & method of the experiment Answering any questions or discussing problems subjects may

have with the study